1
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Frigerio M, V M Freire R, Soares TA, Amenitsch H, Leser ME, Salentinig S. Interfacial structurization between triolein and water from pH and buffer ions. J Colloid Interface Sci 2024; 665:1091-1101. [PMID: 38548506 DOI: 10.1016/j.jcis.2024.03.089] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2023] [Revised: 03/09/2024] [Accepted: 03/11/2024] [Indexed: 04/17/2024]
Abstract
HYPOTHESIS Understanding and manipulating the oil/water interface is important across various industries, including food, pharmaceuticals, cosmetics, and detergents. Many of these processes occur under elevated pH conditions in buffer systems, where base-catalyzed hydrolysis of triglyceride ester bonds leads to amphiphilic reaction products such as fatty acids. EXPERIMENTS Here, pH-triggered alterations of the triolein/water interface are analyzed in the presence of phosphate (PB) and tris(hydroxymethyl)aminomethane (TRIS). Ellipsometry at the liquid/liquid interface, tensiometry, and scanning small angle X-ray scattering are used to study the formation of structures at the oil/water interface. Confocal Raman microscopy, nuclear magnetic resonance spectroscopy, and in silico modeling analyze compositional changes in the interfacial region. FINDINGS pH and buffer ions were discovered to significantly modify the triglyceride/water interface, contrary to the decane/water control. Decreasing interfacial tensions from 32.4 to 2.2 mN/m upon pH increase from 6.5 to 9.5 is seen with multilamellar interfacial layers forming at pH around 9.0 in the presence of TRIS. Oleic acid from triolein hydrolysis and its further interaction with TRIS is held responsible for this. The new understanding can guide the design of pH- and ion-responsive functional materials and optimize industrial processes involving triglyceride/water interfaces.
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Affiliation(s)
- Matteo Frigerio
- Department of Chemistry, University of Fribourg, Chemin Du Musée 9, 1700 Fribourg, Switzerland
| | - Rafael V M Freire
- Department of Chemistry, University of Fribourg, Chemin Du Musée 9, 1700 Fribourg, Switzerland
| | - Thereza A Soares
- Department of Chemistry, FFCLRP, University of São Paulo, Ribeirão Preto-SP, Brazil; Hylleraas Centre for Quantum Molecular Sciences, University of Oslo, Oslo, Norway
| | - Heinz Amenitsch
- Institute for Inorganic Chemistry, Graz University of Technology, Stremayergasse 9/V, Graz 8010, Austria
| | - Martin E Leser
- Department of Chemistry, University of Fribourg, Chemin Du Musée 9, 1700 Fribourg, Switzerland
| | - Stefan Salentinig
- Department of Chemistry, University of Fribourg, Chemin Du Musée 9, 1700 Fribourg, Switzerland.
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2
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Watts S, Hänni E, Smith GN, Mahmoudi N, Freire RVM, Lim S, Salentinig S. Human antimicrobial peptide inactivation mechanism of enveloped viruses. J Colloid Interface Sci 2024; 657:971-981. [PMID: 38096780 DOI: 10.1016/j.jcis.2023.11.055] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2023] [Revised: 11/03/2023] [Accepted: 11/09/2023] [Indexed: 01/02/2024]
Abstract
HYPOTHESIS Enveloped viruses are pivotal in causing various illnesses, including influenza and COVID-19. The antimicrobial peptide LL-37, a critical part of the human innate immune system, exhibits potential as an antiviral agent capable of thwarting these viral threats. Its mode of action involves versatile and non-specific interactions that culminate in dismantling the viral envelope, ultimately rendering the viruses inert. However, the exact mechanism of action is not yet understood. EXPERIMENTS Here, the mechanism of LL-37 triggered changes in the structure and function of an enveloped virus is investigated. The bacteriophage "Phi6" is used as a surrogate for pathogenic enveloped viruses. Small angle X-ray and neutron scattering combined with light scattering techniques demonstrate that LL-37 actively integrates into the virus's lipid envelope. FINDINGS LL-37 addition to Phi6 leads to curvature modification in the lipid bilayer, ultimately separating the envelope from the nucleocapsid. Additional biological assays confirm the loss of virus infectivity in the presence of LL-37, which coincides with the structural transformations. The results provide a fundamental understanding of the structure-activity relationship related to enveloped viruses. The knowledge of peptide-virus interactions can guide the design of future peptide-based antiviral drugs and therapies.
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Affiliation(s)
- Samuel Watts
- Department of Chemistry, University of Fribourg, Chemin du Musée 9, 1700 Fribourg, Switzerland; School of Chemistry, Chemical Engineering and Biotechnology, 70 Nanyang Drive, Block N1.3, Nanyang Technological University, Singapore 637457, Singapore
| | - Eliane Hänni
- Department of Chemistry, University of Fribourg, Chemin du Musée 9, 1700 Fribourg, Switzerland
| | - Gregory N Smith
- ISIS Neutron and Muon Souce, Science and Technology Facilities Council, Rutherford Appleton Laboratory, Didcot OX11 0QX, United Kingdom
| | - Najet Mahmoudi
- ISIS Neutron and Muon Souce, Science and Technology Facilities Council, Rutherford Appleton Laboratory, Didcot OX11 0QX, United Kingdom
| | - Rafael V M Freire
- Department of Chemistry, University of Fribourg, Chemin du Musée 9, 1700 Fribourg, Switzerland
| | - Sierin Lim
- School of Chemistry, Chemical Engineering and Biotechnology, 70 Nanyang Drive, Block N1.3, Nanyang Technological University, Singapore 637457, Singapore
| | - Stefan Salentinig
- Department of Chemistry, University of Fribourg, Chemin du Musée 9, 1700 Fribourg, Switzerland.
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3
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Kadakia P, Valentin JDP, Hong L, Watts S, Hameed OA, Walch M, Salentinig S. Biocompatible Rhamnolipid Self-Assemblies with pH-Responsive Antimicrobial Activity. Adv Healthc Mater 2024; 13:e2302596. [PMID: 37935580 DOI: 10.1002/adhm.202302596] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2023] [Revised: 10/23/2023] [Indexed: 11/09/2023]
Abstract
There is an urgent need for alternative antimicrobial materials due to the growing challenge of bacteria becoming resistant to conventional antibiotics. This study demonstrates the creation of a biocompatible pH-switchable antimicrobial material by combining bacteria-derived rhamnolipids (RL) and food-grade glycerol monooleate (GMO). The integration of RL into dispersed GMO particles, with an inverse-type liquid crystalline cubic structure in the core, leads to colloidally stable supramolecular materials. The composition and pH-triggered structural transformations are studied with small-angle X-ray scattering, cryogenic transmission electron microscopy, and dynamic light scattering. The composition-structure-activity relationship is analyzed and optimized to target bacteria at acidic pH values of acute wounds. The new RL/GMO dispersions reduce Staphylococcus aureus (S. aureus) populations by 7-log after 24 h of treatment with 64 µg mL-1 of RL and prevent biofilm formation at pH = 5.0, but have no activity at pH = 7.0. Additionally, the system is active against methicillin-resistant S. aureus (MRSA) with minimum inhibitory concentration of 128 µg mL-1 at pH 5.0. No activity is found against several Gram-negative bacteria at pH 5.0 and 7.0. The results provide a fundamental understanding of lipid self-assembly and the design of lipid-based biomaterials, which can further guide the development of alternative bio-based solutions to combat bacteria.
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Affiliation(s)
- Parth Kadakia
- Department of Chemistry, University of Fribourg, Chemin du Musée 9, Fribourg, 1700, Switzerland
| | - Jules D P Valentin
- Department of Chemistry, University of Fribourg, Chemin du Musée 9, Fribourg, 1700, Switzerland
| | - Linda Hong
- Department of Chemistry, University of Fribourg, Chemin du Musée 9, Fribourg, 1700, Switzerland
| | - Samuel Watts
- Department of Chemistry, University of Fribourg, Chemin du Musée 9, Fribourg, 1700, Switzerland
| | - Owais Abdul Hameed
- Department of Chemistry, University of Fribourg, Chemin du Musée 9, Fribourg, 1700, Switzerland
- Anatomy Unit, Department of Oncology, Microbiology and Immunology, Faculty of Science and Medicine, University of Fribourg, Fribourg, 1700, Switzerland
| | - Michael Walch
- Anatomy Unit, Department of Oncology, Microbiology and Immunology, Faculty of Science and Medicine, University of Fribourg, Fribourg, 1700, Switzerland
| | - Stefan Salentinig
- Department of Chemistry, University of Fribourg, Chemin du Musée 9, Fribourg, 1700, Switzerland
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4
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Molliet A, Doninelli S, Hong L, Tran B, Debas M, Salentinig S, Kilbinger AFM, Casalini T. Solvent Dependent Folding of an Amphiphilic Polyaramid. J Am Chem Soc 2023; 145:27830-27837. [PMID: 38084077 DOI: 10.1021/jacs.3c11026] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2023]
Abstract
A series of synthetic alternating and amphiphilic aromatic amide polymers were synthesized by a step growth polymerization. Alternating meta- and para-linkages were introduced to force the polymer chain into a helical shape in the highly polar solvent water. The polymers were analyzed by 1H NMR spectroscopy and SEC in polar aprotic solvents such as DMSO and DMF. However, the polymers also showed good solubility in water. 1H NMR spectroscopy, small-angle X-ray scattering, and dynamic light scattering provided clear evidence of polymer folding in water but not DMF. We employed parallel tempering metadynamics in the well-tempered ensemble (PTMetaD-WTE) to simulate the free energy surfaces of an analogous model polymer in DMF and water. The simulations gave a molecular model of an unfolded structure in DMF and a helically folded tubular structure in water.
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Affiliation(s)
- Angélique Molliet
- Department of Chemistry, University of Fribourg, Chemin du Musée 9, CH-1700 Fribourg, Switzerland
| | - Samantha Doninelli
- Department of Chemistry, University of Fribourg, Chemin du Musée 9, CH-1700 Fribourg, Switzerland
| | - Linda Hong
- Department of Chemistry, University of Fribourg, Chemin du Musée 9, CH-1700 Fribourg, Switzerland
| | - Bettina Tran
- Department of Chemistry, University of Fribourg, Chemin du Musée 9, CH-1700 Fribourg, Switzerland
| | - Meron Debas
- Department of Chemistry, University of Fribourg, Chemin du Musée 9, CH-1700 Fribourg, Switzerland
| | - Stefan Salentinig
- Department of Chemistry, University of Fribourg, Chemin du Musée 9, CH-1700 Fribourg, Switzerland
| | - Andreas F M Kilbinger
- Department of Chemistry, University of Fribourg, Chemin du Musée 9, CH-1700 Fribourg, Switzerland
| | - Tommaso Casalini
- Department of Chemistry and Applied Bioscience, Institute for Chemical and Bioengineering, ETH Zurich, Vladimir-Prelog-Weg 1-5/10, Zürich 8093, Switzerland
- Polymer Engineering Laboratory, Institute for Mechanical Engineering and Materials Technology, University of Applied Sciences and Arts of Southern Switzerland (SUPSI), Via la Santa 1, Lugano 6962, Switzerland
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5
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Manca M, Zhang C, Vasconcelos de Melo Freire R, Scheffold F, Salentinig S. Single particle investigation of triolein digestion using optical manipulation, polarized video microscopy, and SAXS. J Colloid Interface Sci 2023; 649:1039-1046. [PMID: 37406476 DOI: 10.1016/j.jcis.2023.06.022] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2023] [Revised: 05/18/2023] [Accepted: 06/05/2023] [Indexed: 07/07/2023]
Abstract
HYPOTHESIS Understanding how soft colloids, such as food emulsion droplets, transform based on their environment is critical for various applications, including drug and nutrient delivery and biotechnology. However, the mechanisms behind colloidal transformations within individual oil droplets still need to be better understood. EXPERIMENTS This study employs optical micromanipulation with microfluidics and polarized optical video microscopy to investigate the pancreatic lipase- and pH-triggered colloidal transformations in a single triolein droplet. Small-angle X-ray scattering (SAXS) provides complementary statistical insights and allows for detailed structural assignment. FINDINGS Optical video microscopy recorded the transformation of individual triolein emulsion droplets, with the smooth surface of these spherical particles becoming rough and the entire volume eventually being affected. The polarized microscopy revealed the coexistence of at least two distinct structures in a single particle during digestion, with their ratio and distribution altered by pH. The SAXS analysis assigned the optical anisotropy to emulsified inverse hexagonal- and multilamellar phases, coexisting with isotropic structures such as the micellar cubic phase. These results can help understand the phase transformations inside an emulsion droplet during triglyceride digestion and guide the design of advanced food emulsions.
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Affiliation(s)
- Marco Manca
- Department of Chemistry, University of Fribourg, Chemin du Musée 9, 1700 Fribourg, Switzerland
| | - Chi Zhang
- Department of Physics, University of Fribourg, Chemin du Musée 3, 1700 Fribourg, Switzerland
| | | | - Frank Scheffold
- Department of Physics, University of Fribourg, Chemin du Musée 3, 1700 Fribourg, Switzerland
| | - Stefan Salentinig
- Department of Chemistry, University of Fribourg, Chemin du Musée 9, 1700 Fribourg, Switzerland.
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6
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Debas M, Freire RVM, Salentinig S. Supramolecular design of CO 2-responsive lipid nanomaterials. J Colloid Interface Sci 2023; 637:513-521. [PMID: 36724665 DOI: 10.1016/j.jcis.2023.01.060] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2022] [Revised: 01/06/2023] [Accepted: 01/11/2023] [Indexed: 01/15/2023]
Abstract
HYPOTHESIS Stimuli-responsive materials can innovate in various fields, including food and pharmaceutical sciences. Their response to a specific stimulus can be utilized to release loaded bioactive molecules or sense their presence. The biocompatibility and abundance of CO2 in the environment make it an exciting stimulus for such applications. We hypothesize the formation of CO2-responsive self-assemblies of oleyl-amidine in water. Their integration into glycerol-monooleate-based (GMO) dispersions is further thought to form CO2-switchable liquid crystalline nanoparticles. The switch from an non-charged acetamidine surfactant to its cationic amidinium form triggers curvature changes that ultimately induces phase transitions. EXPERIMENTS The CO2-switchable lipid (E)-N,N-dimethyl-N-((Z)-octadec-9-en1-yl)acetimidamide (OAm) is synthesized and formulated into emulsions and dispersed liquid crystals with GMO. The supramolecular structure and its response to CO2 are characterized using small angle X-ray scattering, dynamic light scattering, ζ-potential measurements and cryogenic transmission electron microscopy. FINDINGS Depending on the composition, OAm is discovered to self-assemble into a variety of CO2-responsive lyotropic liquid crystalline structures that can be dispersed in excess water. CO2-triggered colloidal transformations from unstructured OAm-in-water emulsions to direct micelles; dispersed inverse hexagonal phase to direct rod-like micelles, and sponge phase to vesicles are discovered. These structural changes are driven by the reaction of OAm's amidine headgroup with CO2. The results provide a fundamental understanding of CO2-triggered functional nanomaterials and may guide their future design into delivery platforms and biosensors.
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Affiliation(s)
- Meron Debas
- Department of Chemistry, University of Fribourg, Chemin du Musée 9, 1700 Fribourg, Switzerland
| | - Rafael V M Freire
- Department of Chemistry, University of Fribourg, Chemin du Musée 9, 1700 Fribourg, Switzerland
| | - Stefan Salentinig
- Department of Chemistry, University of Fribourg, Chemin du Musée 9, 1700 Fribourg, Switzerland.
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7
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Cortat Y, Nedyalkova M, Schindler K, Kadakia P, Demirci G, Nasiri Sovari S, Crochet A, Salentinig S, Lattuada M, Steiner OM, Zobi F. Computer-Aided Drug Design and Synthesis of Rhenium Clotrimazole Antimicrobial Agents. Antibiotics (Basel) 2023; 12:antibiotics12030619. [PMID: 36978486 PMCID: PMC10044843 DOI: 10.3390/antibiotics12030619] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2023] [Revised: 03/16/2023] [Accepted: 03/17/2023] [Indexed: 03/30/2023] Open
Abstract
In the context of the global health issue caused by the growing occurrence of antimicrobial resistance (AMR), the need for novel antimicrobial agents is becoming alarming. Inorganic and organometallic complexes represent a relatively untapped source of antibiotics. Here, we report a computer-aided drug design (CADD) based on a 'scaffold-hopping' approach for the synthesis and antibacterial evaluation of fac-Re(I) tricarbonyl complexes bearing clotrimazole (ctz) as a monodentate ligand. The prepared molecules were selected following a pre-screening in silico analysis according to modification of the 2,2'-bipyridine (bpy) ligand in the coordination sphere of the complexes. CADD pointed to chiral 4,5-pinene and 5,6-pinene bipyridine derivatives as the most promising candidates. The corresponding complexes were synthesized, tested toward methicillin-sensitive and -resistant S. aureus strains, and the obtained results evaluated with regard to their binding affinity with a homology model of the S. aureus MurG enzyme. Overall, the title species revealed very similar minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) values as those of the reference compound used as the scaffold in our approach. The obtained docking scores advocate the viability of 'scaffold-hopping' for de novo design, a potential strategy for more cost- and time-efficient discovery of new antibiotics.
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Affiliation(s)
- Youri Cortat
- Department of Chemistry, Fribourg University, Chemin Du Musée 9, 1700 Fribourg, Switzerland
| | - Miroslava Nedyalkova
- Department of Chemistry, Fribourg University, Chemin Du Musée 9, 1700 Fribourg, Switzerland
| | - Kevin Schindler
- Department of Chemistry, Fribourg University, Chemin Du Musée 9, 1700 Fribourg, Switzerland
| | - Parth Kadakia
- Department of Chemistry, Fribourg University, Chemin Du Musée 9, 1700 Fribourg, Switzerland
| | - Gozde Demirci
- Department of Chemistry, Fribourg University, Chemin Du Musée 9, 1700 Fribourg, Switzerland
| | - Sara Nasiri Sovari
- Department of Chemistry, Fribourg University, Chemin Du Musée 9, 1700 Fribourg, Switzerland
| | - Aurelien Crochet
- Department of Chemistry, Fribourg University, Chemin Du Musée 9, 1700 Fribourg, Switzerland
| | - Stefan Salentinig
- Department of Chemistry, Fribourg University, Chemin Du Musée 9, 1700 Fribourg, Switzerland
| | - Marco Lattuada
- Department of Chemistry, Fribourg University, Chemin Du Musée 9, 1700 Fribourg, Switzerland
| | - Olimpia Mamula Steiner
- Haute école d'Ingénierie et d'Architecture, University of Applied Sciences Western Switzerland HES-SO, Pérolles 80, 1700 Fribourg, Switzerland
| | - Fabio Zobi
- Department of Chemistry, Fribourg University, Chemin Du Musée 9, 1700 Fribourg, Switzerland
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8
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Peng L, Matellan C, Bosch-Fortea M, Gonzalez-Molina J, Frigerio M, Salentinig S, Del Rio Hernandez A, Gautrot JE. Mesenchymal Stem Cells Sense the Toughness of Nanomaterials and Interfaces. Adv Healthc Mater 2023; 12:e2203297. [PMID: 36717365 DOI: 10.1002/adhm.202203297] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2022] [Revised: 01/20/2023] [Indexed: 02/01/2023]
Abstract
Stem cells are known to sense and respond to the mechanical properties of biomaterials. In turn, cells exert forces on their environment that can lead to striking changes in shape, size and contraction of associated tissues, and may result in mechanical disruption and functional failure. However, no study has so far correlated stem cell phenotype and biomaterials toughness. Indeed, disentangling toughness-mediated cell response from other mechanosensing processes has remained elusive as it is particularly challenging to uncouple Youngs' or shear moduli from toughness, within a range relevant to cell-generated forces. In this report, it is shown how the design of the macromolecular architecture of polymer nanosheets regulates interfacial toughness, independently of interfacial shear storage modulus, and how this controls the expansion of mesenchymal stem cells at liquid interfaces. The viscoelasticity and toughness of poly(l-lysine) nanosheets assembled at liquid-liquid interfaces is characterised via interfacial shear rheology. The local (microscale) mechanics of nanosheets are characterised via magnetic tweezer-assisted interfacial microrheology and the thickness of these assemblies is determined from in situ ellipsometry. Finally, the response of mesenchymal stem cells to adhesion and culture at corresponding interfaces is investigated via immunostaining and confocal microscopy.
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Affiliation(s)
- Lihui Peng
- Institute of Bioengineering, Queen Mary University of London, Mile End Road, E1 4NS, London, UK.,Cellular and Molecular Biomechanical Laboratory, Department of Bioengineering, Imperial College London, London, SW7 2AZ, UK
| | - Carlos Matellan
- School of Engineering and Materials Science, Queen Mary, University of London, Mile End Road, London, E1 4NS, UK
| | - Minerva Bosch-Fortea
- Institute of Bioengineering, Queen Mary University of London, Mile End Road, E1 4NS, London, UK.,Cellular and Molecular Biomechanical Laboratory, Department of Bioengineering, Imperial College London, London, SW7 2AZ, UK
| | - Jordi Gonzalez-Molina
- Institute of Bioengineering, Queen Mary University of London, Mile End Road, E1 4NS, London, UK.,Cellular and Molecular Biomechanical Laboratory, Department of Bioengineering, Imperial College London, London, SW7 2AZ, UK
| | - Matteo Frigerio
- Department of Chemistry, University of Fribourg, Chemin du Musée 9, Fribourg, 1700, Switzerland
| | - Stefan Salentinig
- Department of Chemistry, University of Fribourg, Chemin du Musée 9, Fribourg, 1700, Switzerland
| | - Armando Del Rio Hernandez
- School of Engineering and Materials Science, Queen Mary, University of London, Mile End Road, London, E1 4NS, UK
| | - Julien E Gautrot
- Institute of Bioengineering, Queen Mary University of London, Mile End Road, E1 4NS, London, UK.,Cellular and Molecular Biomechanical Laboratory, Department of Bioengineering, Imperial College London, London, SW7 2AZ, UK
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9
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Sarker M, Watts S, Salentinig S, Lim S. Protein Cage-Stabilized Emulsions: Formulation and Characterization. Methods Mol Biol 2023; 2671:219-239. [PMID: 37308648 DOI: 10.1007/978-1-0716-3222-2_13] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/14/2023]
Abstract
The formulation of Pickering emulsions using protein cages is gaining interest for applications in molecular delivery. Despite the growing interest, methods to investigate the at the liquid-liquid interface are limited. This chapter describes standard methods to formulate and protocols to characterize protein cage-stabilized emulsions. The characterization methods are dynamic light scattering (DLS), intrinsic fluorescence spectroscopy (TF), circular dichroism (CD), and small angle X-ray scattering (SAXS). Combining these methods allows understanding of the protein cage nanostructure at the oil/water interface.
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Affiliation(s)
- Mridul Sarker
- School of Chemistry, Chemical Engineering and Biotechnology, Nanyang Technological University, Singapore, Singapore
| | - Samuel Watts
- School of Chemistry, Chemical Engineering and Biotechnology, Nanyang Technological University, Singapore, Singapore
- Department of Chemistry, University of Fribourg, Fribourg, Switzerland
| | - Stefan Salentinig
- Department of Chemistry, University of Fribourg, Fribourg, Switzerland.
| | - Sierin Lim
- School of Chemistry, Chemical Engineering and Biotechnology, Nanyang Technological University, Singapore, Singapore.
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10
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Bor G, Lin JH, Lin KY, Chen HC, Prajnamitra RP, Salentinig S, Hsieh PCH, Moghimi SM, Yaghmur A. PEGylation of Phosphatidylglycerol/Docosahexaenoic Acid Hexosomes with d-α-Tocopheryl Succinate Poly(ethylene glycol) 2000 Induces Morphological Transformation into Vesicles with Prolonged Circulation Times. ACS Appl Mater Interfaces 2022; 14:48449-48463. [PMID: 36271846 DOI: 10.1021/acsami.2c14375] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/16/2023]
Abstract
Considering the broad therapeutic potential of omega-3 polyunsaturated fatty acids such as docosahexaenoic acid (DHA), here we study the effect of PEGylation of DHA-incorporated hexosomes on their physicochemical characteristics and biodistribution following intravenous injection into mice. Hexosomes were formed from phosphatidylglycerol and DHA with a weight ratio of 3:2. PEGylation was achieved through the incorporation of either d-α-tocopheryl succinate poly(ethylene glycol)2000 (TPGS-mPEG2000) or 1,2-distearoyl-sn-glycero-3-phosphoethanolamine-N-methoxy-poly(ethylene glycol)2000 (DSPE-mPEG2000) at a concentration of 1.5 wt %. Nanoparticle tracking analysis, synchrotron small-angle scattering, and cryo-transmission electron microscopy were employed to characterize the nanodispersions. The results show that PEGylated lipids induce a structural transition from an inverse hexagonal (H2) phase inside the nanoparticles (hexosomes) to a lamellar (Lα) phase (vesicles). We also followed the effect of mouse plasma on the nanodispersion size distribution, number, and morphology because changes brought by plasma constituents could regulate the in vivo performance of intravenously injected nanodispersions. For comparative biodistribution studies, fluorescently labeled nanodispersions of equivalent quantum yields were injected intravenously into healthy mice. TPGS-mPEG2000-induced vesicles were most effective in avoiding hepatosplenic clearance at early time points. In an orthotopic xenograft murine model of glioblastoma, TPGS-mPEG2000-induced vesicles also showed improved localization to the brain compared with native hexosomes. We discuss these observations and their implications for the future design of injectable lyotropic nonlamellar liquid crystalline drug delivery nanosystems for therapeutic interventions of brain and liver diseases.
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Affiliation(s)
- Gizem Bor
- Department of Pharmacy, Faculty of Health and Medical Sciences, University of Copenhagen, Universitetsparken 2, Copenhagen ØDK-2100, Denmark
| | - Jen-Hao Lin
- Institute of Biomedical Sciences, Academia Sinica, Taipei 11511529, Taiwan
| | - Kui-Yu Lin
- Department of Life Sciences, Tzu Chi University, Hualien97004, Taiwan
| | - Hung-Chih Chen
- Institute of Biomedical Sciences, Academia Sinica, Taipei 11511529, Taiwan
| | | | - Stefan Salentinig
- Department of Chemistry, University of Fribourg, Chemin du Musée 9, Fribourg1700, Switzerland
| | - Patrick C H Hsieh
- Institute of Biomedical Sciences, Academia Sinica, Taipei 11511529, Taiwan
- Department of Medicine and Stem Cell and Regenerative Medicine Center, University of Wisconsin, Madison, Wisconsin53705, United States
- Institute of Medical Genomics and Proteomics and Institute of Clinical Medicine, National Taiwan University College of Medicine, Taipei 10011529, Taiwan
| | - Seyed Moein Moghimi
- School of Pharmacy, Newcastle University, Newcastle upon TyneNE1 7RU, U.K
- Translational and Clinical Research Institute, Newcastle University, Newcastle upon TyneNE2 4HH, U.K
- Colorado Center for Nanomedicine and Nanosafety, Skaggs School of Pharmacy and Pharmaceutical Sciences, University of Colorado Anschutz Medical Campus, Aurora, Colorado80045, United States
| | - Anan Yaghmur
- Department of Pharmacy, Faculty of Health and Medical Sciences, University of Copenhagen, Universitetsparken 2, Copenhagen ØDK-2100, Denmark
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11
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Abstract
Viruses are nature's own nanoparticles that are highly symmetric and monodisperse in size and shape with well-defined surface chemistry. They have evolved for optimal cell interactions, genetic information delivery and replication by the host cell over millions of years. These features render them into very efficient pathogens that place a severe burden onto the health of our society. At the same time, they are highly interesting objects for colloidal studies and building blocks for advanced bio-inspired materials for health applications. Their characterisation requires sophisticated experimental techniques such as scattering of X-rays, neutrons, and light to probe structures and interactions from the nanometre to the micrometre length-scale in solution. This contribution summarizes the recent progress in the field of virus self-assembly and virus-based biopolymer composites for advanced material design. It discusses the advances and highlights some of the challenges in the characterization of structure and dynamics in these materials with a focus on scattering techniques. It further demonstrates selected applications in the field of food and water purification.
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Affiliation(s)
- Samuel Watts
- Department of Chemistry, University of Fribourg, Chemin du Musée 9, CH-1700 Fribourg
| | - Bettina Tran
- Department of Chemistry, University of Fribourg, Chemin du Musée 9, CH-1700 Fribourg
| | - Stefan Salentinig
- Department of Chemistry, University of Fribourg, Chemin du Musée 9, CH-1700 Fribourg.
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12
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Manca M, Zhang C, Scheffold F, Salentinig S. Optical tweezer platform for the characterization of pH-triggered colloidal transformations in the oleic acid/water system. J Colloid Interface Sci 2022; 627:610-620. [PMID: 35872418 DOI: 10.1016/j.jcis.2022.07.028] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2022] [Revised: 06/30/2022] [Accepted: 07/04/2022] [Indexed: 10/17/2022]
Abstract
HYPOTHESIS Soft colloidal particles that respond to their environment have innovative potential for many fields ranging from food and health to biotechnology and oil recovery. The in situ characterisation of colloidal transformations that triggers the functional response remain a challenge. EXPERIMENTS This study demonstrates the combination of an optical micromanipulation platform, polarized optical video microscopy and microfluidics in a comprehensive approach for the analysis of pH-driven structural transformations in emulsions. The new platform, together with synchrotron small angle X-ray scattering, was then applied to research the food-relevant, pH-responsive, oleic acid in water system. FINDINGS The experiments demonstrate structural transformations in individual oleic acid particles from micron-sized onion-type multilamellar oleic acid vesicles at pH 8.6, to nanostructured emulsions at pH < 8.0, and eventually oil droplets at pH < 6.5. The smooth particle-water interface of the onion-type vesicles at pH 8.6 was transformed into a rough particle surface at pH below 7.5. The pH-triggered changes of the interfacial tension at the droplet-water interface together with mass transport owing to structural transformations induced a self-propelled motion of the particle. The results of this study contribute to the fundamental understanding of the structure-property relationship in pH-responsive emulsions for nutrient and drug delivery applications.
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Affiliation(s)
- Marco Manca
- Department of Chemistry, University of Fribourg, Chemin du Musée 9, 1700 Fribourg, Switzerland
| | - Chi Zhang
- Department of Physics, University of Fribourg, Chemin du Musée 3, 1700 Fribourg, Switzerland
| | - Frank Scheffold
- Department of Physics, University of Fribourg, Chemin du Musée 3, 1700 Fribourg, Switzerland.
| | - Stefan Salentinig
- Department of Chemistry, University of Fribourg, Chemin du Musée 9, 1700 Fribourg, Switzerland.
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13
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Clerc M, Tekin C, Ulrich S, Freire RVM, Salentinig S, Bruns N, Boesel LF. Donor-Acceptor Stenhouse Adduct-Polydimethylsiloxane-Conjugates for Enhanced Photoswitching in Bulk Polymers. Macromol Rapid Commun 2022; 43:e2200120. [PMID: 35396766 DOI: 10.1002/marc.202200120] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2022] [Revised: 03/14/2022] [Indexed: 11/09/2022]
Abstract
Donor-acceptor Stenhouse adducts (DASAs) are a rapidly emerging class of visible light-activated photochromes and DASA-functionalized polymers hold great promise as biocompatible photoresponsive materials. However, the photoswitching performance of DASAs in solid polymer matrices is often low, particularly in polymeric materials below their glass transition temperature. To overcome this limitation, DASAs are conjugated to polydimethylsiloxanes which have a glass transition temperature far below room temperature and which can create a mobile molecular environment around the DASAs for achieving more solution-like photoswitching kinetics in bulk polymers. The dispersion of DASAs conjugated to such flexible oligomers into solid polymer matrices allows for more effective and tunable DASA photoswitching in stiff polymers, such as poly(methyl methacrylate), without requiring modifications of the matrix. The photoswitching of conjugates with varying polymer molecular weight, linker type and architecture is characterized via time-dependent UV-Vis spectroscopy in organic solvents and blended into polymethacrylate films. In addition, DASA-functionalized polydimethylsiloxane networks that are accessible by the same synthetic route provide an alternative solution for achieving fast and efficient DASA photoswitching in the bulk owing to their intrinsic softness and flexibility. These findings may contribute to the development of DASA-functionalized materials with better tunable, more effective, and more reversible modulation of their optical properties. This article is protected by copyright. All rights reserved.
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Affiliation(s)
- Michèle Clerc
- Empa, Swiss Federal Laboratories for Materials Science and Technology, Laboratory for Biomimetic Membranes and Textiles, Lerchenfeldstrasse 5, St. Gallen, 9014, Switzerland.,University of Fribourg, Department of Chemistry, Chemin du Musée 9, Fribourg, 1700, Switzerland.,Department of Pure and Applied Chemistry, University of Strathclyde, Thomas Graham Building, 295 Cathedral Street, Glasgow, G1 1XL, United Kingdom
| | - Cem Tekin
- Empa, Swiss Federal Laboratories for Materials Science and Technology, Laboratory for Biomimetic Membranes and Textiles, Lerchenfeldstrasse 5, St. Gallen, 9014, Switzerland
| | - Sebastian Ulrich
- Empa, Swiss Federal Laboratories for Materials Science and Technology, Laboratory for Biomimetic Membranes and Textiles, Lerchenfeldstrasse 5, St. Gallen, 9014, Switzerland
| | - Rafael V M Freire
- University of Fribourg, Department of Chemistry, Chemin du Musée 9, Fribourg, 1700, Switzerland
| | - Stefan Salentinig
- University of Fribourg, Department of Chemistry, Chemin du Musée 9, Fribourg, 1700, Switzerland
| | - Nico Bruns
- Department of Pure and Applied Chemistry, University of Strathclyde, Thomas Graham Building, 295 Cathedral Street, Glasgow, G1 1XL, United Kingdom
| | - Luciano F Boesel
- Empa, Swiss Federal Laboratories for Materials Science and Technology, Laboratory for Biomimetic Membranes and Textiles, Lerchenfeldstrasse 5, St. Gallen, 9014, Switzerland
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14
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Pal S, Mandal A, Hong L, Ortuso RD, Petri-Fink A, Salentinig S, Kilbinger AFM. Native Chemical Ligation: Ultrafast Synthesis of Block Copolymers. Macromolecules 2022. [DOI: 10.1021/acs.macromol.2c00154] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Subhajit Pal
- Department of Chemistry, University of Fribourg, Chemin du Musée 9, CH-1700 Fribourg, Switzerland
| | - Ankita Mandal
- Department of Chemistry, University of Fribourg, Chemin du Musée 9, CH-1700 Fribourg, Switzerland
| | - Linda Hong
- Department of Chemistry, University of Fribourg, Chemin du Musée 9, CH-1700 Fribourg, Switzerland
| | - Roberto D. Ortuso
- Adolphe Merkle Institute, University of Fribourg, Chemin des Verdiers 4, CH-1700 Fribourg, Switzerland
| | - Alke Petri-Fink
- Adolphe Merkle Institute, University of Fribourg, Chemin des Verdiers 4, CH-1700 Fribourg, Switzerland
| | - Stefan Salentinig
- Department of Chemistry, University of Fribourg, Chemin du Musée 9, CH-1700 Fribourg, Switzerland
| | - Andreas F. M. Kilbinger
- Department of Chemistry, University of Fribourg, Chemin du Musée 9, CH-1700 Fribourg, Switzerland
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15
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Hong L, Salentinig S. Functional food colloids: studying structure and interactions during digestion. Curr Opin Food Sci 2022. [DOI: 10.1016/j.cofs.2022.100817] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
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16
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Rasi V, Hameed OA, Matthey P, Bera S, Grandgenett DP, Salentinig S, Walch M, Hoft DF. Improved Purification of Human Granzyme A/B and Granulysin Using a Mammalian Expression System. Front Immunol 2022; 13:830290. [PMID: 35300343 PMCID: PMC8921980 DOI: 10.3389/fimmu.2022.830290] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2021] [Accepted: 02/08/2022] [Indexed: 01/14/2023] Open
Abstract
Cytotoxic lymphocytes release proteins contained within the cytoplasmic cytolytic granules after recognition of infected or tumor target cells. These cytotoxic granular proteins (namely granzymes, granulysin, and perforin) are key immunological mediators within human cellular immunity. The availability of highly purified cytotoxic proteins has been fundamental for understanding their function in immunity and mechanistic involvement in sepsis and autoimmunity. Methods for recovery of native cytotoxic proteins can be problematic leading to: 1) the co-purification of additional proteins, confounding interpretation of function, and 2) low yields of highly purified proteins. Recombinant protein expression of individual cytolytic components can overcome these challenges. The use of mammalian expression systems is preferred for optimal post-translational modifications and avoidance of endotoxin contamination. Some of these proteins have been proposed for host directed human therapies (e.g. - granzyme A), or treatment of systemic infections or tumors as in granulysin. We report here a novel expression system using HEK293T cells for cost-effective purification of high yields of human granzymes (granzyme A and granzyme B) and granulysin with enhanced biological activity than previous reports. The resulting proteins are free of native contaminants, fold correctly, and remain enzymatically active. Importantly, these improvements have also led to the first purification of biologically active recombinant human granulysin in high yields from a mammalian system. This method can be used as a template for purification of many other secreted cellular proteins and may lead to advances for human medicine.
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Affiliation(s)
- Valerio Rasi
- Department of Molecular Microbiology and Immunology, Saint Louis University School of Medicine, Saint Louis, MO, United States,Department of Internal Medicine, Division of Infectious Diseases, Allergy and Immunology, Saint Louis University School of Medicine, Saint Louis, MO, United States
| | - Owais Abdul Hameed
- Anatomy Unit, Department of Oncology, Microbiology and Immunology, Faculty of Science and Medicine, University of Fribourg, Fribourg, Switzerland,Department of Chemistry, Faculty of Science and Medicine, University of Fribourg, Fribourg, Switzerland
| | - Patricia Matthey
- Anatomy Unit, Department of Oncology, Microbiology and Immunology, Faculty of Science and Medicine, University of Fribourg, Fribourg, Switzerland
| | - Sibes Bera
- Department of Molecular Microbiology and Immunology, Saint Louis University School of Medicine, Saint Louis, MO, United States
| | - Duane P. Grandgenett
- Department of Molecular Microbiology and Immunology, Saint Louis University School of Medicine, Saint Louis, MO, United States
| | - Stefan Salentinig
- Department of Chemistry, Faculty of Science and Medicine, University of Fribourg, Fribourg, Switzerland
| | - Michael Walch
- Anatomy Unit, Department of Oncology, Microbiology and Immunology, Faculty of Science and Medicine, University of Fribourg, Fribourg, Switzerland,*Correspondence: Daniel F. Hoft, ; Michael Walch,
| | - Daniel F. Hoft
- Department of Molecular Microbiology and Immunology, Saint Louis University School of Medicine, Saint Louis, MO, United States,Department of Internal Medicine, Division of Infectious Diseases, Allergy and Immunology, Saint Louis University School of Medicine, Saint Louis, MO, United States,*Correspondence: Daniel F. Hoft, ; Michael Walch,
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17
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Hong L, Gontsarik M, Amenitsch H, Salentinig S. Human Antimicrobial Peptide Triggered Colloidal Transformations in Bacteria Membrane Lipopolysaccharides. Small 2022; 18:e2104211. [PMID: 34825488 DOI: 10.1002/smll.202104211] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/17/2021] [Revised: 09/29/2021] [Indexed: 06/13/2023]
Abstract
Growing concerns of bacterial resistance against conventional antibiotics shifts the research focus toward antimicrobial peptide (AMP)-based materials. Most AMPs kill gram-negative bacteria by destroying their inner membrane, but have to first pass the outer membrane covered with lipopolysaccharides (LPS). Their interplay with the LPS is crucial for bactericidal activity, but is yet to be elucidated in detail. In this study, self-assemblies of Escherichia coli LPS with the human cathelicidin AMP LL-37, free and encapsulated into glyceryl monooleate (GMO) lipid nanoparticles, are analyzed using synchrotron small angle X-ray scattering, dynamic light scattering, and cryogenic transmission electron microscopy. Circular dichroism spectroscopy is used to study modifications in LL-37's secondary structure. LPS is found to form elongated micelles and the addition of LL-37 induces their transformation to multilamellar structures. LPS' addition to GMO cubosomes triggers the swelling of the internal cubic structure, while in multilamellar GMO/LL-37 nanocarriers it causes transitions into unstructured particles. The insights on the interactions among LPS and LL-37, in its free form or encapsulated in GMO dispersions, may guide the design of LPS-responsive antimicrobial nanocarriers. The findings may further assist the formulation of antimicrobial nanomaterials with enhanced penetration of LPS layers for improved destruction of bacterial membranes.
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Affiliation(s)
- Linda Hong
- Department of Chemistry, University of Fribourg, Chemin du Musée 9, Fribourg, 1700, Switzerland
| | - Mark Gontsarik
- Department of Chemistry, University of Fribourg, Chemin du Musée 9, Fribourg, 1700, Switzerland
| | - Heinz Amenitsch
- Institute for Inorganic Chemistry, Graz University of Technology, Stremayergasse 9/V, Graz, 8010, Austria
| | - Stefan Salentinig
- Department of Chemistry, University of Fribourg, Chemin du Musée 9, Fribourg, 1700, Switzerland
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18
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Vasylevskyi SI, Raffy G, Salentinig S, Del Guerzo A, Fromm KM, Bassani DM. Multifunctional Anthracene-Based Ni-MOF with Encapsulated Fullerenes: Polarized Fluorescence Emission and Selective Separation of C 70 from C 60. ACS Appl Mater Interfaces 2022; 14:1397-1403. [PMID: 34967204 DOI: 10.1021/acsami.1c19141] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/14/2023]
Abstract
We report an anthracene-based Ni-MOF [Ni(II) metal-organic framework, {[Ni(μ2-L)2Cl2]·x(C6H6)·y(MeOH)}n (1), L = anthracene-9,10-diylbis(methylene)diisonicotinate] whose crystal structure reveals the presence of hexagonal channels with a pore size of 1.4 nm that can accommodate guests such as C60 and C70. Both confocal fluorescence and Raman microscopy results are in agreement with a homogeneous distribution of fullerenes throughout the single crystals of 1. Efficient energy transfer from 1 to the fullerenes was observed, which emitted partially polarized fluorescence emission. Stronger binding between 1 and C70 versus C60 was confirmed from HPLC analysis of the dissolved material and provides a basis for the selective retention of C70 in liquid chromatography columns packed with 1.
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Affiliation(s)
- Serhii I Vasylevskyi
- Chemistry Department, University of Fribourg, Chemin du Musee 9, Fribourg 1700, Switzerland
- University of Bordeaux, ISM CNRS UMR 5255, Talence 33400, France
| | - Guillaume Raffy
- University of Bordeaux, ISM CNRS UMR 5255, Talence 33400, France
| | - Stefan Salentinig
- Chemistry Department, University of Fribourg, Chemin du Musee 9, Fribourg 1700, Switzerland
| | - André Del Guerzo
- University of Bordeaux, ISM CNRS UMR 5255, Talence 33400, France
| | - Katharina M Fromm
- Chemistry Department, University of Fribourg, Chemin du Musee 9, Fribourg 1700, Switzerland
| | - Dario M Bassani
- University of Bordeaux, ISM CNRS UMR 5255, Talence 33400, France
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19
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Abstract
Lipid-enveloped viruses, such as Ebola, influenza, or coronaviruses, are a major threat to human health. Ethanol is an efficient disinfectant that is widely used to inactivate these viruses and prevent their transmission. However, the interactions between ethanol and enveloped viruses leading to their inactivation are not yet fully understood. This study demonstrates the link between ethanol-induced viral inactivation and the nanostructural and chemical transformations of the model virus Phi6, an 85 nm diameter lipid-enveloped bacterial virus that is commonly used as surrogate for human pathogenic viruses. The virus morphology was investigated using small-angle X-ray scattering and dynamic light scattering and was related to its infectivity. The Phi6's surface chemistry was characterized by cryogenic X-ray photoelectron spectroscopy, and the modifications in protein structure were assessed by circular dichroism and fluorescence spectroscopy. Ethanol-triggered structural modifications were found in the lipid envelope, detaching from the protein capsid and forming coexisting nanostructures.
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Affiliation(s)
- Samuel Watts
- Department of Chemistry, University of Fribourg, Chemin du Musée 9, 1700 Fribourg, Switzerland
- Laboratory for Biointerfaces, Empa, Swiss Federal Laboratories for Material Science and Technology, Lerchenfeldstrasse 5, 9014 St. Gallen, Switzerland
| | | | - Stefan Salentinig
- Department of Chemistry, University of Fribourg, Chemin du Musée 9, 1700 Fribourg, Switzerland
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20
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Bor G, Salentinig S, Şahin E, Nur Ödevci B, Roursgaard M, Liccardo L, Hamerlik P, Moghimi SM, Yaghmur A. Cell medium-dependent dynamic modulation of size and structural transformations of binary phospholipid/ω-3 fatty acid liquid crystalline nano-self-assemblies: Implications in interpretation of cell uptake studies. J Colloid Interface Sci 2021; 606:464-479. [PMID: 34399363 DOI: 10.1016/j.jcis.2021.07.149] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2021] [Revised: 07/21/2021] [Accepted: 07/29/2021] [Indexed: 10/20/2022]
Abstract
Lyotropic non-lamellar liquid crystalline (LLC) nanoparticles, with their tunable structural features and capability of loading a wide range of drugs and reporter probes, are emerging as versatile injectable nanopharmaceuticals. Secondary emulsifiers, such as Pluronic block copolymers, are commonly used for colloidal stabilization of LLC nanoparticles, but their inclusion often compromises the biological safety (e.g., poor hemocompatibility and enhanced cytotoxicity) of the formulation. Here, we introduce a library of colloidally stable, structurally tunable, and pH-responsive lamellar and non-lamellar liquid crystalline nanoparticles from binary mixtures of a phospholipid (phosphatidylglycerol) and three types of omega-3 fatty acids (ω-3 PUFAs), prepared in the absence of a secondary emulsifier and organic solvents. We study formulation size distribution, morphological heterogeneity, and the arrangement of their internal self-assembled architectures by nanoparticle tracking analysis, synchrotron small-angle X-ray scattering, and cryo-transmission electron microscopy. The results show the influence of type and concentration of ω-3 PUFAs in nanoparticle structural transitions spanning from a lamellar (Lα) phase to inverse discontinuous (micellar) cubic Fd3m and hexagonal phase (H2) phases, respectively. We further report on cell-culture medium-dependent dynamic fluctuations in nanoparticle size, number and morphology, and simultaneously monitor uptake kinetics in two human cell lines. We discuss the role of these multiparametric biophysical transformations on nanoparticle-cell interaction kinetics and internalization mechanisms. Collectively, our findings contribute to the understanding of fundamental steps that are imperative for improved engineering of LLC nanoparticles with necessary attributes for pharmaceutical development.
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Affiliation(s)
- Gizem Bor
- Department of Pharmacy, Faculty of Health and Medical Sciences, University of Copenhagen, Universitetsparken 2, DK-2100 Copenhagen Ø, Denmark
| | - Stefan Salentinig
- Department of Chemistry, University of Fribourg, Chemin du Musée 9, 1700 Fribourg, Switzerland
| | - Evrim Şahin
- Department of Pharmacy, Faculty of Health and Medical Sciences, University of Copenhagen, Universitetsparken 2, DK-2100 Copenhagen Ø, Denmark
| | - Begüm Nur Ödevci
- Department of Pharmacy, Faculty of Health and Medical Sciences, University of Copenhagen, Universitetsparken 2, DK-2100 Copenhagen Ø, Denmark
| | - Martin Roursgaard
- Department of Public Health, Section of Environmental Health, University of Copenhagen, Øster Farimagsgade 5A, DK-1014 Copenhagen K, Denmark
| | - Letizia Liccardo
- Department of Molecular Science and Nanosystems, Ca' Foscari Università di Venezia, Via Torino 155, Venezia Mestre, Italy
| | - Petra Hamerlik
- Brain Tumor Biology, Danish Cancer Society Research Center, Strandboulevarden 49, DK-2100 Copenhagen Ø, Denmark
| | - Seyed Moein Moghimi
- School of Pharmacy, Newcastle University, Newcastle upon Tyne, NE1 7RU, UK; Translational and Clinical Research Institute, Newcastle University, Newcastle upon Tyne NE2 4HH, UK; Colorado Center for Nanomedicine and Nanosafety, Skaggs School of Pharmacy and Pharmaceutical Sciences, University of Colorado Anschutz Medical Campus, Aurora, CO 80045, USA.
| | - Anan Yaghmur
- Department of Pharmacy, Faculty of Health and Medical Sciences, University of Copenhagen, Universitetsparken 2, DK-2100 Copenhagen Ø, Denmark.
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21
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Freire RV, Pillco-Valencia Y, da Hora GC, Ramstedt M, Sandblad L, Soares TA, Salentinig S. Antimicrobial peptide induced colloidal transformations in bacteria-mimetic vesicles: Combining in silico tools and experimental methods. J Colloid Interface Sci 2021; 596:352-363. [DOI: 10.1016/j.jcis.2021.03.060] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2020] [Revised: 03/09/2021] [Accepted: 03/11/2021] [Indexed: 01/21/2023]
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22
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Watts S, Maniura-Weber K, Siqueira G, Salentinig S. Virus pH-Dependent Interactions with Cationically Modified Cellulose and Their Application in Water Filtration. Small 2021; 17:e2100307. [PMID: 34146389 DOI: 10.1002/smll.202100307] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/17/2021] [Revised: 05/22/2021] [Indexed: 06/12/2023]
Abstract
Norovirus and Rotavirus are among the pathogens causing a large number of disease outbreaks due to contaminated water. These viruses are nanoscale particles that are difficult to remove by common filtration approaches which are based on physical size exclusion, and require adsorption-based filtration methods. This study reports the pH-responsive interactions of viruses with cationic-modified nanocellulose and demonstrates a filter material that adsorbs nanoscale viruses and can be regenerated by changing the solution's pH. The bacteria viruses Qbeta and MS2, with diameters below 30 nm but different surface properties, are used to evaluate the pH-dependency of the interactions and the filtration process. Small angle X-ray scattering, cryogenic transmission electron microscopy, and ζ-potential measurements are used to study the interactions and analyze changes in their nanostructure and surface properties of the virus upon adsorption. The virus removal capacity of the cationic cellulose-based aerogel filter is 99.9% for MS2 and 93.6% for Qbeta, at pH = 7.0; and desorption of mostly intact viruses occurs at pH = 3.0. The results contribute to the fundamental understanding of pH-triggered virus-nanocellulose self-assembly and can guide the design of sustainable and environmentally friendly adsorption-based virus filter materials as well as phage and virus-based materials.
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Affiliation(s)
- Samuel Watts
- Biointerfaces Lab, Empa, Swiss Federal Laboratories for Material Science and Technology, Lerchenfeldstrasse 5, St. Gallen, 9014, Switzerland
- Department of Chemistry, University of Fribourg, Chemin du Musée 9, Fribourg, 1700, Switzerland
| | - Katharina Maniura-Weber
- Biointerfaces Lab, Empa, Swiss Federal Laboratories for Material Science and Technology, Lerchenfeldstrasse 5, St. Gallen, 9014, Switzerland
| | - Gilberto Siqueira
- Cellulose and Wood Material Lab, Empa, Swiss Federal Laboratories for Material Science and Technology, Überlandstrasse 129, Dübendorf, 8600, Switzerland
| | - Stefan Salentinig
- Department of Chemistry, University of Fribourg, Chemin du Musée 9, Fribourg, 1700, Switzerland
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23
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Zabara M, Ren Q, Amenitsch H, Salentinig S. Bioinspired Antimicrobial Coatings from Peptide-Functionalized Liquid Crystalline Nanostructures. ACS Appl Bio Mater 2021; 4:5295-5303. [PMID: 35007010 DOI: 10.1021/acsabm.1c00415] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
Surface-associated microbial infections and contaminations are a major challenge in various fields including the food and health sectors. This study demonstrates the design of antimicrobial coatings based on the self-assembly of the food-grade amphiphilic lipid glycerol monooleate with the human cathelicidin-derived antimicrobial peptide LL-37. Structural properties of the coating and their alterations with composition were studied using advanced experimental methods including synchrotron grazing-incidence small-angle X-ray scattering and ellipsometry. The integration of the LL-37 and its potential release from the nanostructured films into the surrounding solution was characterized with confocal Raman microscopy. Additional biological evaluation studies with clinically relevant bacterial strains, namely, Pseudomonas aeruginosa (Gram-negative) and Staphylococcus aureus (Gram-positive), were performed to investigate the antimicrobial activity of the coatings. Significant killing activity of the coating was found against both bacterial strains. The presented findings contribute to the fundamental understanding of lipid-peptide self-assembly on the surface and may open up a promising strategy for designing simple, sustainable antimicrobial coatings for medical and food applications.
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Affiliation(s)
- Mahsa Zabara
- Department of Chemistry, University of Fribourg, Chemin du Musée 9, 1700 Fribourg, Switzerland
| | - Qun Ren
- Laboratory for Biointerfaces, Department Materials Meet Life, Empa Swiss Federal Laboratories for Materials Science and Technology, Lerchenfeldstrasse 5, 9014 St. Gallen, Switzerland
| | - Heinz Amenitsch
- Institute for Inorganic Chemistry, Graz University of Technology, Stremayergasse 9/V, 8010 Graz, Austria
| | - Stefan Salentinig
- Department of Chemistry, University of Fribourg, Chemin du Musée 9, 1700 Fribourg, Switzerland
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24
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Shchukarev A, Backman E, Watts S, Salentinig S, Urban CF, Ramstedt M. Applying Cryo-X-ray Photoelectron Spectroscopy to Study the Surface Chemical Composition of Fungi and Viruses. Front Chem 2021; 9:666853. [PMID: 34124001 PMCID: PMC8194281 DOI: 10.3389/fchem.2021.666853] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2021] [Accepted: 05/14/2021] [Indexed: 11/21/2022] Open
Abstract
Interaction between microorganisms and their surroundings are generally mediated via the cell wall or cell envelope. An understanding of the overall chemical composition of these surface layers may give clues on how these interactions occur and suggest mechanisms to manipulate them. This knowledge is key, for instance, in research aiming to reduce colonization of medical devices and device-related infections from different types of microorganisms. In this context, X-ray photoelectron spectroscopy (XPS) is a powerful technique as its analysis depth below 10 nm enables studies of the outermost surface structures of microorganism. Of specific interest for the study of biological systems is cryogenic XPS (cryo-XPS). This technique allows studies of intact fast-frozen hydrated samples without the need for pre-treatment procedures that may cause the cell structure to collapse or change due to the loss of water. Previously, cryo-XPS has been applied to study bacterial and algal surfaces with respect to their composition of lipids, polysaccharides and peptide (protein and/or peptidoglycan). This contribution focuses onto two other groups of microorganisms with widely different architecture and modes of life, namely fungi and viruses. It evaluates to what extent existing models for data treatment of XPS spectra can be applied to understand the chemical composition of their very different surface layers. XPS data from model organisms as well as reference substances representing specific building blocks of their surface were collected and are presented. These results aims to guide future analysis of the surface chemical composition of biological systems.
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Affiliation(s)
| | - Emelie Backman
- Department of Clinical Microbiology, Umeå University, Umeå, Sweden.,Umeå Centre for Microbial Research (UCMR), Umeå University, Umeå, Sweden
| | - Samuel Watts
- Biointerfaces Lab, Empa, Swiss Federal Laboratories for Material Science and Technology, St. Gallen, Switzerland.,Department of Chemistry, Fribourg University, Fribourg, Switzerland
| | | | - Constantin F Urban
- Department of Clinical Microbiology, Umeå University, Umeå, Sweden.,Umeå Centre for Microbial Research (UCMR), Umeå University, Umeå, Sweden
| | - Madeleine Ramstedt
- Department of Chemistry, Umeå University, Umeå, Sweden.,Umeå Centre for Microbial Research (UCMR), Umeå University, Umeå, Sweden
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25
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Gontsarik M, Yaghmur A, Salentinig S. Dispersed liquid crystals as pH-adjustable antimicrobial peptide nanocarriers. J Colloid Interface Sci 2021; 583:672-682. [DOI: 10.1016/j.jcis.2020.09.081] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2020] [Revised: 09/15/2020] [Accepted: 09/19/2020] [Indexed: 02/06/2023]
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Abstract
Colloidal structures are crucial components in biological systems and provide a vivid and seemingly infinite source of inspiration for the design of functional bio-inspired materials. They form multi-dimensional confinements and shape living matter, and transport and protect bioactive molecules in harsh biological environments such as the stomach. Recently, colloidal nanostructures based on natural antimicrobial peptides have emerged as promising alternatives to conventional antibiotics. This contribution summarizes the recent progress in the understanding and design of these bio-inspired antimicrobial nanomaterials, and discusses their advances in the form of dispersions and as surface coatings. Their potential for applications in future food and healthcare materials is also highlighted. Further, it discusses challenges in the characterization of structure and dynamics in these materials.
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Affiliation(s)
- Mahsa Zabara
- Department of Chemistry, University of Fribourg, Chemin du Musée 9, CH-1700 Fribourg, Switzerland
| | - Linda Hong
- Department of Chemistry, University of Fribourg, Chemin du Musée 9, CH-1700 Fribourg, Switzerland
| | - Stefan Salentinig
- Department of Chemistry, University of Fribourg, Chemin du Musée 9, CH-1700 Fribourg, Switzerland;,
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27
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Hempt C, Gontsarik M, Buerki-Thurnherr T, Hirsch C, Salentinig S. Nanostructure generation during milk digestion in presence of a cell culture model simulating the small intestine. J Colloid Interface Sci 2020; 574:430-440. [PMID: 32344233 DOI: 10.1016/j.jcis.2020.04.059] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2020] [Revised: 04/15/2020] [Accepted: 04/15/2020] [Indexed: 01/07/2023]
Abstract
HYPOTHESIS The development of advanced oral delivery systems for bioactive compounds requires the fundamental understanding of the digestion process within the gastrointestinal tract. Towards this goal, dynamic invitro digestion models, capable of characterising the molecular as well as colloidal aspects of food, together with their biological interactions with relevant invitro cell culture models, are essential. EXPERIMENTS In this study, we demonstrate a novel digestion model that combines flow-through time resolved small angle X-ray scattering (SAXS) with an invitro Caco-2/HT-29 cell co-culture model that also contained a mucus layer. This set-up allows the dynamic insitu characterisation of colloidal structures and their transport across a viable intestinal cell layer during simulated digestion. FINDINGS An integrated online SAXS - invitro cell co-culture model was developed and applied to study the digestion of nature's own emulsion, milk. The impact of the invitro cell culture on the digestion-triggered formation and evolution of highly ordered nanostructures in milk is demonstrated. Reported is also the crucial role of the mucus layer on top of the cell layer, protecting the cells from degradation by digestive juice components such as lipase. The novel model can open unique possibilities for the dynamic investigation of colloidal structure formation during lipid digestion and their effect on the uptake of bioactive molecules by the cells.
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Affiliation(s)
- Claudia Hempt
- Laboratory for Particles-Biology Interactions, Empa, Swiss Federal Laboratories for Materials Science and Technology, Lerchenfeldstrasse 5, 9014 St. Gallen, Switzerland; Department of Health Sciences and Technology, ETH Zürich, Zürich, Switzerland
| | - Mark Gontsarik
- Laboratory for Biointerfaces, Empa, Swiss Federal Laboratories for Materials Science and Technology, Lerchenfeldstrasse 5, 9014 St. Gallen, Switzerland
| | - Tina Buerki-Thurnherr
- Laboratory for Particles-Biology Interactions, Empa, Swiss Federal Laboratories for Materials Science and Technology, Lerchenfeldstrasse 5, 9014 St. Gallen, Switzerland
| | - Cordula Hirsch
- Laboratory for Particles-Biology Interactions, Empa, Swiss Federal Laboratories for Materials Science and Technology, Lerchenfeldstrasse 5, 9014 St. Gallen, Switzerland
| | - Stefan Salentinig
- Department of Chemistry, University of Fribourg, Chemin du Musée 9, 1700 Fribourg, Switzerland.
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28
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Watts S, Julian TR, Maniura-Weber K, Graule T, Salentinig S. Colloidal Transformations in MS2 Virus Particles: Driven by pH, Influenced by Natural Organic Matter. ACS Nano 2020; 14:1879-1887. [PMID: 32027487 DOI: 10.1021/acsnano.9b08112] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
Enteric viruses, such as enterovirus, norovirus, and rotavirus, are among the leading causes of disease outbreaks due to contaminated drinking and recreational water. Viruses are difficult to remove from water through filtration based on physical size exclusion-for example by gravity-driven filters-due to their nanoscale size. To understand virus removal in drinking water treatment systems, the colloidal nanostructure of a model virus, the MS2 bacteriophage, has been investigated in relation to the effect of pH and natural organic matter in water. Dynamic light scattering, small-angle X-ray scattering, and cryogenic transmission electron microscopy demonstrated that the water pH has a major influence on the colloidal structure of the virus: The bacteriophage MS2's structure in water in the range pH = 7.0 to 9.0 was found to be spherical with core-shell-type structure with a total diameter of 27 nm and a core radius of around 8 nm. Reversible transformations from 27 nm particles at pH = 7.0 to micrometer-sized aggregates at pH = 3.0 were observed. In addition, the presence of natural organic matter that simulates the organic components present in surface water was found to enhance repulsion between virus particles, reduce the size of aggregates, and promote disaggregation upon pH increase. These findings allow a better understanding of virus interactions in water and have implications for water treatment using filtration processes and coagulation. The results will further guide the comprehensive design of advanced virus filter materials.
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Affiliation(s)
- Samuel Watts
- Biointerfaces Lab , Empa, Swiss Federal Laboratories for Material Science and Technology , Lerchenfeldstrasse 5 , 9014 St. Gallen , Switzerland
| | - Timothy R Julian
- Eawag , Swiss Federal Institute of Aquatic Science , Überlandstrasse 133 , 8600 Dübendorf , Switzerland
- Swiss Tropical and Public Health Institute , 4002 Basel , Switzerland
- University of Basel , 4003 Basel , Switzerland
| | - Katharina Maniura-Weber
- Biointerfaces Lab , Empa, Swiss Federal Laboratories for Material Science and Technology , Lerchenfeldstrasse 5 , 9014 St. Gallen , Switzerland
| | - Thomas Graule
- High Performance Ceramics Lab , Empa, Swiss Federal Laboratories for Materials Science and Technology , Überlandstrasse 129 , 8600 Dübendorf , Switzerland
| | - Stefan Salentinig
- Biointerfaces Lab , Empa, Swiss Federal Laboratories for Material Science and Technology , Lerchenfeldstrasse 5 , 9014 St. Gallen , Switzerland
- Department of Chemistry , University of Fribourg , Chemin du Musée 9 , 1700 Fribourg , Switzerland
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29
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Innocenti Malini R, Zabara M, Gontsarik M, Maniura-Weber K, Rossi RM, Spano F, Salentinig S. Self-assembly of glycerol monooleate with the antimicrobial peptide LL-37: a molecular dynamics study. RSC Adv 2020; 10:8291-8302. [PMID: 35497861 PMCID: PMC9049931 DOI: 10.1039/c9ra10037g] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2019] [Accepted: 02/04/2020] [Indexed: 11/21/2022] Open
Abstract
Over the past decade, the rapid increase in the incidence of antibiotic-resistant bacteria has promoted research towards alternative therapeutics such as antimicrobial peptides (AMPs), but their biodegradability limits their application. Encapsulation into nanocarriers based on the self-assembly of surfactant-like lipids is emerging as a promising strategy for the improvement of AMPs' stability and their protection against degradation when in biological media. An in-depth understanding of the interactions between the structure-forming lipids and AMPs is required for the design of nanocarriers. This in silico study, demonstrates the self-assembly of the amphiphilic lipid glycerol monooleate (GMO) with the antimicrobial peptide LL-37 into nanocarriers on the molecular scale. Molecular dynamics (MD) simulations show the formation of direct micelles, with either one or two interacting LL-37, and vesicles in this two-component system in agreement with experimental results from small-angle X-ray scattering studies. The hydrophobic contacts between LL-37 and GMOs in water appear responsible for the formation of these nanoparticles. The results also suggest that the enhanced antimicrobial efficiency of LL-37 in these nanocarriers that was previously observed experimentally can be explained by the availability of its side chains with charged amino acids, an increase of the electrostatic interaction and a decrease of the peptide's conformational entropy upon interacting with GMO. The results of this study contribute to the fundamental understanding of lipid-AMP interactions and may guide the comprehensive design of lipid-based self-assembled nanocarriers for antimicrobial peptides.
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Affiliation(s)
- R Innocenti Malini
- Empa, Swiss Federal Laboratories for Materials Science and Technology, Laboratory for Biomimetic Membranes and Textiles Lerchenfeldstrasse 5 9014 St. Gallen Switzerland
| | - M Zabara
- Laboratory for Biointerfaces, Department Materials meet Life Lerchenfeldstrasse 5 9014 St. Gallen Switzerland
| | - M Gontsarik
- Laboratory for Biointerfaces, Department Materials meet Life Lerchenfeldstrasse 5 9014 St. Gallen Switzerland
| | - K Maniura-Weber
- Laboratory for Biointerfaces, Department Materials meet Life Lerchenfeldstrasse 5 9014 St. Gallen Switzerland
| | - R M Rossi
- Empa, Swiss Federal Laboratories for Materials Science and Technology, Laboratory for Biomimetic Membranes and Textiles Lerchenfeldstrasse 5 9014 St. Gallen Switzerland
| | - F Spano
- Empa, Swiss Federal Laboratories for Materials Science and Technology, Laboratory for Biomimetic Membranes and Textiles Lerchenfeldstrasse 5 9014 St. Gallen Switzerland
| | - S Salentinig
- Laboratory for Biointerfaces, Department Materials meet Life Lerchenfeldstrasse 5 9014 St. Gallen Switzerland
- Department of Chemistry, University of Fribourg Chemin du Musée 9 1700 Fribourg Switzerland
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30
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Yaghmur A, Lotfi S, Ariabod SA, Bor G, Gontsarik M, Salentinig S. Internal Lamellar and Inverse Hexagonal Liquid Crystalline Phases During the Digestion of Krill and Astaxanthin Oil-in-Water Emulsions. Front Bioeng Biotechnol 2019; 7:384. [PMID: 31867316 PMCID: PMC6906996 DOI: 10.3389/fbioe.2019.00384] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2019] [Accepted: 11/18/2019] [Indexed: 12/12/2022] Open
Abstract
Krill oil represents an important alternative natural source of omega-3 (ω-3) polyunsaturated fatty acids (PUFAs). Considering the beneficial health effects of these essential fatty acids, particularly in various disorders including cancer, cardiovascular, and inflammation diseases, it is of paramount importance to gain insight into the digestibility of krill oil. In this work, we study the fate of krill oil-in-water emulsion, stabilized by sodium caseinate, during lipolysis by coupling time-resolved synchrotron small-angle X-ray scattering (SAXS) to flow-through lipolysis model. For gaining further insight into the effect of ω-3 PUFA-containing oil type on the dynamic structural features occurring during lipolysis, two additional astaxanthin oil-in-water emulsions, stabilized using either sodium caseinate or citrem, were subjected to lipolysis under identical experimental conditions. In addition to the difference in lipid composition in both oils, ω-3 PUFAs in astaxanthin oil, similar to fish oil, exist in the form of triacylglycerols; whereas most of those in krill oil are bound to phospholipids. SAXS showed the formation of highly ordered nanostructures on exposure of these food emulsions to the lipolysis medium: the detection of a biphasic feature of coexisting inverse hexagonal (H2) and lamellar (Lα) liquid crystalline phases in the digested krill oil droplets' interiors, as compared to a neat Lα phase in the digested astaxanthin oil droplets. We discuss the dynamic phase behavior and describe the suggested important role of these phases in facilitating the delivery of nutrients throughout the body. In addition, the potential implication in the development of food and drug nanocarriers is briefly described.
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Affiliation(s)
- Anan Yaghmur
- Department of Pharmacy, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Saleh Lotfi
- Department of Pharmacy, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Sarah Atoussa Ariabod
- Department of Pharmacy, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Gizem Bor
- Department of Pharmacy, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Mark Gontsarik
- Laboratory for Biointerfaces, Empa, Swiss Federal Laboratories for Materials Science and Technology, St. Gallen, Switzerland
| | - Stefan Salentinig
- Laboratory for Biointerfaces, Empa, Swiss Federal Laboratories for Materials Science and Technology, St. Gallen, Switzerland.,Department of Chemistry, University of Fribourg, Fribourg, Switzerland
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31
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Gabryelczyk B, Cai H, Shi X, Sun Y, Swinkels PJM, Salentinig S, Pervushin K, Miserez A. Hydrogen bond guidance and aromatic stacking drive liquid-liquid phase separation of intrinsically disordered histidine-rich peptides. Nat Commun 2019; 10:5465. [PMID: 31784535 PMCID: PMC6884462 DOI: 10.1038/s41467-019-13469-8] [Citation(s) in RCA: 78] [Impact Index Per Article: 15.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2019] [Accepted: 11/07/2019] [Indexed: 01/07/2023] Open
Abstract
Liquid-liquid phase separation (LLPS) of intrinsically disordered proteins (IDPs) is involved in both intracellular membraneless organelles and extracellular tissues. Despite growing understanding of LLPS, molecular-level mechanisms behind this process are still not fully established. Here, we use histidine-rich squid beak proteins (HBPs) as model IDPs to shed light on molecular interactions governing LLPS. We show that LLPS of HBPs is mediated though specific modular repeats. The morphology of separated phases (liquid-like versus hydrogels) correlates with the repeats' hydrophobicity. Solution-state NMR indicates that LLPS is a multistep process initiated by deprotonation of histidine residues, followed by transient hydrogen bonding with tyrosine, and eventually by hydrophobic interactions. The microdroplets are stabilized by aromatic clustering of tyrosine residues exhibiting restricted molecular mobility in the nano-to-microsecond timescale according to solid-state NMR experiments. Our findings provide guidelines to rationally design pH-responsive peptides with LLPS ability for various applications, including bioinspired protocells and smart drug-delivery systems.
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Affiliation(s)
- Bartosz Gabryelczyk
- Center for Biomimetic Sensor Science, School of Materials Science and Engineering, Nanyang Technological University (NTU), 50 Nanyang Drive, Singapore, 637553, Singapore
- Department of Bioproducts and Biosystems, School of Chemical Engineering, Aalto University, Kemistintie 1, 02150, Espoo, Finland
| | - Hao Cai
- Center for Biomimetic Sensor Science, School of Materials Science and Engineering, Nanyang Technological University (NTU), 50 Nanyang Drive, Singapore, 637553, Singapore
| | - Xiangyan Shi
- School of Physical and Mathematical Sciences, NTU, 21 Nanyang Link, Singapore, 637371, Singapore
| | - Yue Sun
- Center for Biomimetic Sensor Science, School of Materials Science and Engineering, Nanyang Technological University (NTU), 50 Nanyang Drive, Singapore, 637553, Singapore
| | - Piet J M Swinkels
- Center for Biomimetic Sensor Science, School of Materials Science and Engineering, Nanyang Technological University (NTU), 50 Nanyang Drive, Singapore, 637553, Singapore
- Physical Chemistry and Soft Matter, Wageningen University, 6708 WE, Wageningen, Netherlands
| | - Stefan Salentinig
- Laboratory for Biointerfaces, Department Materials Meet Life, EMPA, CH-9014, St-Gallen, Switzerland
- Department of Chemistry, University of Fribourg, Chemin du Musée 9, 1700, Fribourg, Switzerland
| | - Konstantin Pervushin
- School of Biological Sciences, NTU, 60 Nanyang Drive, Singapore, 637551, Singapore.
| | - Ali Miserez
- Center for Biomimetic Sensor Science, School of Materials Science and Engineering, Nanyang Technological University (NTU), 50 Nanyang Drive, Singapore, 637553, Singapore.
- School of Biological Sciences, NTU, 60 Nanyang Drive, Singapore, 637551, Singapore.
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32
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Abstract
pH-responsive lipid nanocarriers have the potential to selectively target the acidic extracellular pH environment of cancer tissues and may further improve the efficacy of chemotherapeutics by minimizing their toxic side-effects. Here, we present the design and characterization of pH-sensitive nano-self-assemblies of the poorly water-soluble anticancer drug 2-hydroxyoleic acid (2OHOA) with glycerol monooleate (GMO). pH-triggered nanostructural transformations from 2OHOA/GMO nanoparticles with an internal inverse hexagonal structure (hexosomes) at pH around 2.0-3.0, via nanocarriers with an internal inverse bicontinuous cubic structure (cubosomes) at pH 2.0-4.5, to vesicles at pH 4.5-7.4 were observed with synchrotron small-angle X-ray scattering, and cryogenic transmission electron microscopy. ζ-potential measurements highlight that the pH-driven deprotonation of the carboxylic group of 2OHOA, and the resulting charge-repulsions at the lipid-water interface account for these nanostructural alterations. The study provides detailed insight into the pH-dependent self-assembly of 2OHOA with GMO in excess buffer at physiologically relevant pH values, and discusses the effects of pH alterations on modulating their nanostructure. The results may guide the further development of pH-responsive anticancer nanocarriers for the targeted delivery of chemotherapeutics to the local microenvironment of tumor cells.
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Affiliation(s)
- Rama Prajapati
- Department of Pharmacy, Faculty of Health and Medical Sciences , University of Copenhagen , Universitetsparken 2 , DK-2100 Copenhagen Ø , Denmark
| | - Mark Gontsarik
- Laboratory for Biointerfaces , Empa, Swiss Federal Laboratories for Materials Science and Technology , Lerchenfeldstrasse 5 , 9014 St. Gallen , Switzerland
| | - Anan Yaghmur
- Department of Pharmacy, Faculty of Health and Medical Sciences , University of Copenhagen , Universitetsparken 2 , DK-2100 Copenhagen Ø , Denmark
| | - Stefan Salentinig
- Laboratory for Biointerfaces , Empa, Swiss Federal Laboratories for Materials Science and Technology , Lerchenfeldstrasse 5 , 9014 St. Gallen , Switzerland
- Department of Chemistry , University of Fribourg , Chemin du Musée 9 , 1700 Fribourg , Switzerland
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33
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Anantharaman SB, Messmer D, Sadeghpour A, Salentinig S, Nüesch F, Heier J. Excitonic channels from bio-inspired templated supramolecular assembly of J-aggregate nanowires. Nanoscale 2019; 11:6929-6938. [PMID: 30916072 DOI: 10.1039/c8nr10357g] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
Supramolecular assemblies with controlled morphology are of paramount importance for energy transport in organic semiconductors. Despite considerable freedom in molecular design, the preparation of dyes that form one dimensional J-aggregates is challenging. Here, we demonstrate a simple and effective route to functionalize dendronized polymers (DPs) with J-aggregates to construct tubular DP/J-aggregate nanowires. When J-aggregates are adsorbed onto DPs anchored to glass substrates, they assemble into microcrystalline domains typical for J-aggregates adsorbed on functionalized surfaces. Differently, the complexation between the dendronized polymer and J-aggregates in solution leads to dense packing of J-aggregate strands on the periphery of the DPs. Using a layer-by-layer (LBL) technique, DPs loaded with J-aggregates can also be adsorbed onto a DP monolayer. In this case, the thin film absorption spectra are narrower and indicate higher ratios of J-aggregate to monomer and dimer absorption than bare J-aggregates deposited similarly. The demonstration of J-aggregate adsorption on filamentous polymeric templates is a promising step toward artificial 1D light harvesting antennas, with potential applications in opto-electronic devices.
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Affiliation(s)
- Surendra B Anantharaman
- Laboratory for Functional Polymers, Swiss Federal Laboratories for Materials Science and Technology (Empa), Überlandstrasse 129, CH-8600 Dübendorf, Switzerland.
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34
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Gontsarik M, Yaghmur A, Ren Q, Maniura-Weber K, Salentinig S. From Structure to Function: pH-Switchable Antimicrobial Nano-Self-Assemblies. ACS Appl Mater Interfaces 2019; 11:2821-2829. [PMID: 30589253 DOI: 10.1021/acsami.8b18618] [Citation(s) in RCA: 51] [Impact Index Per Article: 10.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
Stimuli-responsive nanocarriers based on lipid self-assemblies have the potential to provide targeted delivery of antimicrobial peptides, limiting their side effects while protecting them from degradation in the biological environments. In the present study, we design and characterize a simple pH-responsive antimicrobial nanomaterial, formed through the self-assembly of oleic acid (OA) with the human cathelicidin LL-37 as a model for an amphiphilic antimicrobial peptide. Colloidal transformations from core-shell cylindrical micelles with a cross-sectional diameter of ∼5.5 nm and a length of ∼23 nm at pH 7.0 to aggregates of branched threadlike micelles at pH 5.0 were detected using synchrotron small-angle X-ray scattering, cryogenic transmission electron microscopy, and dynamic light scattering. Biological in vitro assays using an Escherichia coli bacteria strain showed high antimicrobial activity of the positively charged LL-37/OA aggregates at pH 5.0, which was not caused by the pH conditions themselves. Contrary to that, negligible antimicrobial activity was observed at pH 7.0 for the negatively charged cylindrical micelles. The nanocarrier's ability to switch its biological activity "on" and "off" in response to changes in pH could be used to focus the antimicrobial peptides' action to areas of specific pH in the body. The presented findings contribute to the fundamental understanding of lipid-peptide self-assembly and may open up a promising strategy for designing simple pH-responsive delivery systems for antimicrobial peptides.
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Affiliation(s)
- Mark Gontsarik
- Laboratory for Biointerfaces , Empa Swiss Federal Laboratories for Materials Science and Technology , Lerchenfeldstrasse 5 , 9014 St. Gallen , Switzerland
| | - Anan Yaghmur
- Department of Pharmacy, Faculty of Health and Medical Sciences , University of Copenhagen , Universitetsparken 2 , DK-2100 Copenhagen Ø , Denmark
| | - Qun Ren
- Laboratory for Biointerfaces , Empa Swiss Federal Laboratories for Materials Science and Technology , Lerchenfeldstrasse 5 , 9014 St. Gallen , Switzerland
| | - Katharina Maniura-Weber
- Laboratory for Biointerfaces , Empa Swiss Federal Laboratories for Materials Science and Technology , Lerchenfeldstrasse 5 , 9014 St. Gallen , Switzerland
| | - Stefan Salentinig
- Laboratory for Biointerfaces , Empa Swiss Federal Laboratories for Materials Science and Technology , Lerchenfeldstrasse 5 , 9014 St. Gallen , Switzerland
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35
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Shao X, Bor G, Al-Hosayni S, Salentinig S, Yaghmur A. Structural characterization of self-assemblies of new omega-3 lipids: docosahexaenoic acid and docosapentaenoic acid monoglycerides. Phys Chem Chem Phys 2018; 20:23928-23941. [PMID: 30209464 DOI: 10.1039/c8cp04256j] [Citation(s) in RCA: 35] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
The attractiveness of new omega-3 (ω-3) polyunsaturated fatty acid (PUFA) monoglycerides (MAGs) lies in the amphiphilic nature and the beneficial health effects as PUFA precursors in various disorders including cancer, pulmonary hypertension, and inflammatory diseases. For exploring the potential therapeutic applications of these new amphiphilic lipids, particularly as main lipid constituents in the development of nanocarriers for delivery of drugs and PUFAs, it is of paramount importance to gain insight into their self-assembly behavior on exposure to excess water. This work describes the structural characteristics of self-assemblies based on two newly synthesized MAGs, namely docosahexaenoic acid (MAG-DHA) and docosapentaenoic acid (MAG-DPA) monoglycerides, on exposure to excess water. We found that both lipids tend to form a dominant inverse hexagonal (H2) phase in excess water at 25 °C and a temperature-triggered structural transition to an inverse micellar solution (L2 phase) is detected similar to that recently reported (A. Yaghmur et al., Langmuir, 2017, 33, 14045-14057) for eicosapentaenoic acid monoglyceride (MAG-EPA). An experimental SAXS structural evaluation study on the temperature-dependent behavior of these new monoglycerides is provided, and the effects of unsaturation degree and fatty acyl chain length on the self-assembled structural features in excess water and on the H2-L2 phase transition temperature are discussed. In addition, hexosomes stabilized by using the triblock copolymer F127 and the food-grade emulsifier citrem were investigated to gain insights into the effects of stabilizer and temperature on the internal nanostructure. These nanoparticles are attractive for use in the development of nanocarriers for delivering drugs and/or nutritional compounds as the beneficial health effects of ω-3 PUFA monoglycerides can be combined with those of loaded therapeutic agents or nutraceuticals.
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Affiliation(s)
- Xianrong Shao
- Department of Pharmacy, Faculty of Health and Medical Sciences, University of Copenhagen, Universitetsparken 2, DK-2100 Copenhagen Ø, Denmark.
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36
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Weishaupt R, Heuberger L, Siqueira G, Gutt B, Zimmermann T, Maniura-Weber K, Salentinig S, Faccio G. Enhanced Antimicrobial Activity and Structural Transitions of a Nanofibrillated Cellulose-Nisin Biocomposite Suspension. ACS Appl Mater Interfaces 2018; 10:20170-20181. [PMID: 29767501 DOI: 10.1021/acsami.8b04470] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
Resistance to antibiotics has posed a high demand for novel strategies to fight bacterial infections. Antimicrobial peptides (AMPs) are a promising alternative to conventional antibiotics. However, their poor solubility in water and sensitivity to degradation has limited their application. Here, we report the design of a smart, pH-responsive antimicrobial nanobiocomposite material based on the AMP nisin and 2,2,6,6-tetramethyl-1-piperidinyloxyl-oxidized nanofibrillated cellulose (TONFC). Morphological transformations of the nanoscale structure of nisin functionalized-TONFC fibrils were discovered at pH values between 5.8 and 8.0 using small-angle X-ray scattering. Complementary ζ potential measurements indicate that electrostatic attractions between the negatively charged TONFC surface and the positively charged nisin molecules are responsible for the integration of nisin. Modification of the pH level or increasing the ionic strength reduces the nisin binding capacity of TONFC. Biological evaluation studies using a bioluminescence-based reporter strain of Bacillus subtilis and a clinically relevant strain of Staphylococcus aureus indicated a significantly higher antimicrobial activity of the TONFC-nisin biocomposite compared to the pure nisin against both strains under physiological pH and ionic strength conditions. The in-depth characterization of this new class of antimicrobial biocomposite material based on nanocellulose and nisin may guide the rational design of sustainable antimicrobial materials.
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Affiliation(s)
- Ramon Weishaupt
- Laboratory for Biointerfaces , Empa, Swiss Federal Laboratories for Materials Science and Technology , Lerchenfeldstrasse 5 , CH-9014 St. Gallen , Switzerland
| | - Lukas Heuberger
- Laboratory for Biointerfaces , Empa, Swiss Federal Laboratories for Materials Science and Technology , Lerchenfeldstrasse 5 , CH-9014 St. Gallen , Switzerland
| | - Gilberto Siqueira
- Laboratory for Applied Wood Materials , Empa, Swiss Federal Laboratories for Materials Science and Technology , Überlandstrasse 129 , CH-8600 Dübendorf , Switzerland
| | - Beatrice Gutt
- Laboratory for Biointerfaces , Empa, Swiss Federal Laboratories for Materials Science and Technology , Lerchenfeldstrasse 5 , CH-9014 St. Gallen , Switzerland
| | - Tanja Zimmermann
- Laboratory for Applied Wood Materials , Empa, Swiss Federal Laboratories for Materials Science and Technology , Überlandstrasse 129 , CH-8600 Dübendorf , Switzerland
| | - Katharina Maniura-Weber
- Laboratory for Biointerfaces , Empa, Swiss Federal Laboratories for Materials Science and Technology , Lerchenfeldstrasse 5 , CH-9014 St. Gallen , Switzerland
| | - Stefan Salentinig
- Laboratory for Biointerfaces , Empa, Swiss Federal Laboratories for Materials Science and Technology , Lerchenfeldstrasse 5 , CH-9014 St. Gallen , Switzerland
| | - Greta Faccio
- Laboratory for Biointerfaces , Empa, Swiss Federal Laboratories for Materials Science and Technology , Lerchenfeldstrasse 5 , CH-9014 St. Gallen , Switzerland
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37
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Gontsarik M, Mohammadtaheri M, Yaghmur A, Salentinig S. pH-Triggered nanostructural transformations in antimicrobial peptide/oleic acid self-assemblies. Biomater Sci 2018; 6:803-812. [DOI: 10.1039/c7bm00929a] [Citation(s) in RCA: 46] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
This study reports smart nanostructures based on oleic acid/peptide mixtures in water for the delivery of antimicrobial peptides.
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Affiliation(s)
- Mark Gontsarik
- Laboratory for Biointerfaces
- Department Materials meet Life
- Empa Swiss Federal Laboratories for Materials Science and Technology
- St Gallen
- Switzerland
| | - Mahsa Mohammadtaheri
- Laboratory for Biointerfaces
- Department Materials meet Life
- Empa Swiss Federal Laboratories for Materials Science and Technology
- St Gallen
- Switzerland
| | - Anan Yaghmur
- Department of Pharmacy
- Faculty of Health and Medical Sciences
- University of Copenhagen
- DK-2100 Copenhagen Ø
- Denmark
| | - Stefan Salentinig
- Laboratory for Biointerfaces
- Department Materials meet Life
- Empa Swiss Federal Laboratories for Materials Science and Technology
- St Gallen
- Switzerland
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38
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Salentinig S, Zabara M, Parisse P, Amenitsch H. Formation of highly ordered liquid crystalline coatings – an in situ GISAXS study. Phys Chem Chem Phys 2018; 20:21903-21909. [PMID: 30123907 DOI: 10.1039/c8cp03205j] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
In situ GISAXS and AFM reveal the formation of highly geometrically organized glycerol monooleate based liquid crystalline films on silicon wafers.
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Affiliation(s)
- S. Salentinig
- Laboratory for Biointerfaces
- Department Materials Meet Life
- Empa
- Swiss Federal Laboratories for Materials Science and Technology
- 9014 St. Gallen
| | - Mahsa Zabara
- Laboratory for Biointerfaces
- Department Materials Meet Life
- Empa
- Swiss Federal Laboratories for Materials Science and Technology
- 9014 St. Gallen
| | - P. Parisse
- Elettra Sincrotrone Trieste S.C.p.A
- 34149-Basovizza
- Italy
| | - H. Amenitsch
- Institute for Inorganic Chemistry
- Graz University of Technology
- Stremayergasse 9/V
- 8010 Graz
- Austria
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39
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Yaghmur A, Al-Hosayni S, Amenitsch H, Salentinig S. Structural Investigation of Bulk and Dispersed Inverse Lyotropic Hexagonal Liquid Crystalline Phases of Eicosapentaenoic Acid Monoglyceride. Langmuir 2017; 33:14045-14057. [PMID: 29136473 DOI: 10.1021/acs.langmuir.7b03078] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
Recent studies demonstrated the potential therapeutic use of newly synthesized omega-3 (ω-3) polyunsaturated fatty acid (PUFA) monoglycerides owing to their beneficial health effects in various disorders including cancer and inflammation diseases. To date, the research was mainly focused on exploring the biological effects of these functional lipids. However, to the best of our knowledge, there is no report on the hydration-mediated self assembly of these lipids that leads to the formation of nanostructures, which are attractive for use as vehicles for the delivery of drugs and functional foods. In the present study, we investigated the temperature-composition phase behaviour of eicosapentaenoic acid monoglyceride (MAG-EPA), which is one of the most investigated ω-3 PUFA monoglycerides, during a heating-cooling cycle in the temperature range of 5-60 °C. Experimental synchrotron small-angle X-ray scattering (SAXS) evidence on the formation of a dominant inverse hexagonal (H2) lyotropic liquid crystalline phase and its temperature-induced transition to an inverse micellar solution (L2 phase) is presented for the fully hydrated bulk MAG-EPA system and its corresponding dispersion. We produced colloidal MAG-EPA hexosomes with an internal inverse hexagonal (H2) lyotropic crystalline phase in the presence of F127, a well-known polymeric stabilizer, or citrem, which is a negatively charged food-grade emulsifier. In this work, we report also on the formation of MAG-EPA hexosomes by vortexing MAG-EPA in excess aqueous medium containing F127 at room temperature. This low-energy emulsification method is different than most reported studies in the literature that have demonstrated the need for using a high-energy input during the emulsification step or adding an organic solvent for the formation of such colloidal nonlamellar liquid crystalline dispersions. The designed nanoparticles hold promise for future drug and functional food delivery applications due to their unique structural properties and the potential health-promoting effects of MAG-EPA.
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Affiliation(s)
- Anan Yaghmur
- Department of Pharmacy, Faculty of Health and Medical Sciences, University of Copenhagen , Universitetsparken 2, DK-2100 Copenhagen Ø, Denmark
| | - Sabah Al-Hosayni
- Department of Pharmacy, Faculty of Health and Medical Sciences, University of Copenhagen , Universitetsparken 2, DK-2100 Copenhagen Ø, Denmark
| | - Heinz Amenitsch
- Elettra-Sincrotrone Trieste , Strada Statale 14, 34149 Basovizza, Trieste, Italy
| | - Stefan Salentinig
- Laboratory for Biointerfaces, Empa, Swiss Federal Laboratories for Materials Science and Technology , Lerchenfeldstrasse 5, 9014 St. Gallen, Switzerland
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40
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Faccio G, Salentinig S. Enzyme-Triggered Dissociation of a FRET-Based Protein Biosensor Monitored by Synchrotron SAXS. Biophys J 2017; 113:1731-1737. [PMID: 29045867 DOI: 10.1016/j.bpj.2017.08.044] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2017] [Revised: 08/19/2017] [Accepted: 08/24/2017] [Indexed: 11/19/2022] Open
Abstract
Protein biosensors are widely used for the monitoring of metabolite concentration and enzymatic activities inside living cells and in in vitro applications. Neutrophil elastase (NE) is a serine protease of relevance in inflammatory diseases whose activity can lead to pathological conditions if unregulated. This study focuses on the structural characterization of a biosensor for NE activity based on Förster resonance energy transfer (FRET). The cleavage by NE results in dissociation of the FRET fluorescent protein pair and alteration of the fluorescent emission spectrum. We have used small angle x-ray scattering at a high intensity synchrotron source, combined with model-free analysis of the scattering data, to demonstrate the structure of the biosensor and the effect of its exposure to NE on size and shape. These investigations, together with biochemical studies, established the nanostructure-activity relationship that may contribute to the detailed understanding of the FRET-based biosensor and guide the rational design of new biosensor constructs.
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Affiliation(s)
- Greta Faccio
- Laboratory for Biointerfaces, Department "Materials Meet Life", Empa, Swiss Federal Laboratories for Materials Science and Technology, St. Gallen, Switzerland.
| | - Stefan Salentinig
- Laboratory for Biointerfaces, Department "Materials Meet Life", Empa, Swiss Federal Laboratories for Materials Science and Technology, St. Gallen, Switzerland.
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41
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Cai H, Gabryelczyk B, Manimekalai MSS, Grüber G, Salentinig S, Miserez A. Self-coacervation of modular squid beak proteins - a comparative study. Soft Matter 2017; 13:7740-7752. [PMID: 29043368 DOI: 10.1039/c7sm01352c] [Citation(s) in RCA: 39] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
The beak of the Humboldt squid is a biocomposite material made solely of organic components - chitin and proteins - which exhibits 200-fold stiffness and hardness gradients from the soft base to the exceptionally hard tip (rostrum). The outstanding mechanical properties of the squid beak are achieved via controlled hydration and impregnation of the chitin-based scaffold by protein coacervates. Molecular-based understanding of these proteins is essential to mimic the natural beak material. Here, we present detailed studies of two histidine-rich beak proteins (HBP-1 and -2) that play central roles during beak bio-fabrication. We show that both proteins have the ability to self-coacervate, which is governed intrinsically by the sequence modularity of their C-terminus and extrinsically by pH and ionic strength. We demonstrate that HBPs possess dynamic structures in solution and achieve maximum folding in the coacervate state, and propose that their self-coacervation is driven by hydrophobic interactions following charge neutralization through salt-screening. Finally, we show that subtle differences in the modular repeats of HBPs result in significant changes in the rheological response of the coacervates. This knowledge may be exploited to design self-coacervating polypeptides for a wide range of engineering and biomedical applications, for example bio-inspired composite materials, smart hydrogels and adhesives, and biomedical implants.
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Affiliation(s)
- Hao Cai
- Center for Biomimetic Sensor Science, School of Materials Science and Engineering, Nanyang Technological University (NTU), 50 Nanyang Avenue, Singapore 637553.
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42
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Khaliqi K, Ghazal A, Azmi IDM, Amenitsch H, Mortensen K, Salentinig S, Yaghmur A. Direct monitoring of lipid transfer on exposure of citrem nanoparticles to an ethanol solution containing soybean phospholipids by combining synchrotron SAXS with microfluidics. Analyst 2017; 142:3118-3126. [PMID: 28744529 DOI: 10.1039/c7an00860k] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2023]
Abstract
Lipid exchange among citrem nanoparticles and an ethanol micellar solution containing soy phosphatidylcholine was investigated in situ by coupling small angle X-ray scattering with a microfluidic device. The produced soy phosphatidylcholine/citrem nanoparticles have great potential in the development of hemocompatible nanocarriers for drug delivery.
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Affiliation(s)
- K Khaliqi
- Department of Pharmacy, Faculty of Health and Medical Sciences, University of Copenhagen, Universitetsparken 2, DK-2100 Copenhagen Ø, Denmark.
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43
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Affiliation(s)
- Stefan Salentinig
- Laboratory
for Biointerfaces, Department Materials meet Life, Empa, Swiss Federal Laboratories for Materials Science and Technology, Lerchenfeldstrasse
5, 9014 St. Gallen, Switzerland
| | - Mark Schubert
- Laboratory
for Applied Wood Materials, Empa, Swiss Federal Laboratories for Materials Science and Technology, Ueberlandstrasse 129, 8600 Duebendorf, Switzerland
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44
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Salentinig S, Amenitsch H, Yaghmur A. In Situ Monitoring of Nanostructure Formation during the Digestion of Mayonnaise. ACS Omega 2017; 2:1441-1446. [PMID: 30023634 PMCID: PMC6044745 DOI: 10.1021/acsomega.7b00153] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/09/2017] [Accepted: 03/31/2017] [Indexed: 06/02/2023]
Abstract
Triglycerides in food products such as mayonnaise are a vital source of energy and essential for a complete and healthy diet. Their molecular structures consist of a glycerol backbone esterified with fatty acids on the two outer and the middle positions. During the digestion of triglycerides by pancreatic lipase in the small intestine, the ester bonds on the outer positions are hydrolyzed, leading to amphiphilic monoglycerides and free fatty acids as products. Depending on their chain length and degree of saturation, these products can self-assemble into a variety of structures in excess water. In this study, we report the discovery of highly ordered nanostructures inside of the mayonnaise emulsion droplets during in vitro digestion of mayonnaise under simulated in vivo conditions using time-resolved synchrotron small-angle X-ray scattering. The formation of these structures is most likely linked to their function as a carrier and controlled release system for food nutrients, especially poorly water-soluble components, in the aqueous milieu of the digestive tract. This detailed understanding of nanostructure formation during the digestion of triglyceride-containing food products such as mayonnaise may have fundamental implications for the development of foods with improved nutritional and functional properties.
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Affiliation(s)
- Stefan Salentinig
- Laboratory
for Biointerfaces, Department Materials Meet Life, Empa, Swiss Federal Laboratories for Materials Science and Technology, Lerchenfeldstrasse 5, 9014 St. Gallen, Switzerland
| | - Heinz Amenitsch
- Institute
for Inorganic Chemistry, Graz University
of Technology, Stremayergasse
9/V, 8010 Graz, Austria
| | - Anan Yaghmur
- Department
of Pharmacy, Faculty of Health and Medical Sciences, University of Copenhagen, Universitetsparken 2, DK-2100 Copenhagen Ø, Denmark
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45
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Ghazal A, Gontsarik M, Kutter JP, Lafleur JP, Ahmadvand D, Labrador A, Salentinig S, Yaghmur A. Microfluidic Platform for the Continuous Production and Characterization of Multilamellar Vesicles: A Synchrotron Small-Angle X-ray Scattering (SAXS) Study. J Phys Chem Lett 2017; 8:73-79. [PMID: 27936765 DOI: 10.1021/acs.jpclett.6b02468] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
A microfluidic platform combined with synchrotron small-angle X-ray scattering (SAXS) was used for monitoring the continuous production of multilamellar vesicles (MLVs). Their production was fast and started to evolve within less than 0.43 s of contact between the lipids and the aqueous phase. To obtain nanoparticles with a narrow size distribution, it was important to use a modified hydrodynamic flow focusing (HFF) microfluidic device with narrower microchannels than those normally used for SAXS experiments. Monodispersed MLVs as small as 160 nm in size, with a polydispersity index (PDI) of approximately 0.15 were achieved. The nanoparticles produced were smaller and had a narrower size distribution than those obtained via conventional bulk mixing methods. This microfluidic platform therefore has a great potential for the continuous production of monodispersed NPs.
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Affiliation(s)
- Aghiad Ghazal
- Niels Bohr Institute, University of Copenhagen , Universitetsparken 5, DK-2100 Copenhagen Ø, Denmark
- Department of Pharmacy, Faculty of Health and Medical Sciences, University of Copenhagen , Universitetsparken 2, DK-2100 Copenhagen Ø, Denmark
| | - Mark Gontsarik
- Department of Pharmacy, Faculty of Health and Medical Sciences, University of Copenhagen , Universitetsparken 2, DK-2100 Copenhagen Ø, Denmark
| | - Jörg P Kutter
- Department of Pharmacy, Faculty of Health and Medical Sciences, University of Copenhagen , Universitetsparken 2, DK-2100 Copenhagen Ø, Denmark
| | - Josiane P Lafleur
- Department of Pharmacy, Faculty of Health and Medical Sciences, University of Copenhagen , Universitetsparken 2, DK-2100 Copenhagen Ø, Denmark
| | - Davoud Ahmadvand
- Iran University of Medical Sciences , Shahid Hemmat Highway, Tehran, Iran
| | - Ana Labrador
- MAX IV Laboratory, Lund University , 223 62 Lund, Sweden
| | - Stefan Salentinig
- Laboratory for Biointerfaces, Empa, Swiss Federal Laboratories for Materials Science and Technology , Lerchenfeldstrasse 5, 9014 St. Gallen, Switzerland
| | - Anan Yaghmur
- Department of Pharmacy, Faculty of Health and Medical Sciences, University of Copenhagen , Universitetsparken 2, DK-2100 Copenhagen Ø, Denmark
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46
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Chatzidaki MD, Papadimitriou K, Alexandraki V, Tsirvouli E, Chakim Z, Ghazal A, Mortensen K, Yaghmur A, Salentinig S, Papadimitriou V, Tsakalidou E, Xenakis A. Microemulsions as Potential Carriers of Nisin: Effect of Composition on Structure and Efficacy. Langmuir 2016; 32:8988-8998. [PMID: 27501392 DOI: 10.1021/acs.langmuir.6b02923] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
Water-in-oil (W/O) microemulsions based on either refined olive oil (ROO) or sunflower oil (SO), distilled monoglycerides (DMG), and ethanol were used as nisin carriers in order to ensure its effectiveness as a biopreservative. This work presents experimental evidence on the effects of ethanol concentration, hydration, the nature of oil, and the addition of nisin on the nanostructure of the proposed inverse microemulsions as revealed by electrical conductivity measurements, dynamic light scattering (DLS), small angle X-ray scattering (SAXS), and electron paramagnetic resonance (EPR) spectroscopy. Modeling of representative SAXS profiles was applied to gain further insight into the effects of ethanol and solubilized water content on the inverse swollen micelles' size and morphology. With increasing ethanol content, the overall size of the inverse micelles decreased, whereas hydration resulted in an increase in the micellar size due to the penetration of water into the hydrophilic core of the inverse swollen micelles (hydration-induced swelling behavior). The dynamic properties of the surfactant monolayer were also affected by the nature of the used vegetable oil, the ethanol content, and the presence of the bioactive molecule, as evidenced by EPR spin probing experiments. According to simulation on the experimental spectra, two populations of spin probes at different polarities were revealed. The antimicrobial effect of the encapsulated nisin was evaluated using the well diffusion assay (WDA) technique against Lactococccus lactis. It was found that this encapsulated bacteriocin induced an inhibition of the microorganism growth. The effect was more pronounced at higher ethanol concentrations, but no significant difference was observed between the two used vegetable oils (ROO and SO).
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Affiliation(s)
- Maria D Chatzidaki
- Institute of Biology Medicinal Chemistry & Biotechnology, National Hellenic Research Foundation, Athens, Greece
- MTM, Faculty of Science and Engineering, Örebro University , Örebro, Sweden
| | - Konstantinos Papadimitriou
- Laboratory of Dairy Research, Department of Food Science and Human Nutrition, Agricultural University of Athens , Athens, Greece
| | - Voula Alexandraki
- Laboratory of Dairy Research, Department of Food Science and Human Nutrition, Agricultural University of Athens , Athens, Greece
| | - Eirini Tsirvouli
- Institute of Biology Medicinal Chemistry & Biotechnology, National Hellenic Research Foundation, Athens, Greece
| | - Zena Chakim
- Institute of Biology Medicinal Chemistry & Biotechnology, National Hellenic Research Foundation, Athens, Greece
| | | | | | | | - Stefan Salentinig
- Laboratory for Biointerfaces, Department of Materials Meet Life, Empa. Swiss Federal Laboratories for Materials Science and Technology , St. Gallen, Switzerland
| | - Vassiliki Papadimitriou
- Institute of Biology Medicinal Chemistry & Biotechnology, National Hellenic Research Foundation, Athens, Greece
| | - Effie Tsakalidou
- Laboratory of Dairy Research, Department of Food Science and Human Nutrition, Agricultural University of Athens , Athens, Greece
| | - Aristotelis Xenakis
- Institute of Biology Medicinal Chemistry & Biotechnology, National Hellenic Research Foundation, Athens, Greece
- MTM, Faculty of Science and Engineering, Örebro University , Örebro, Sweden
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47
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Gontsarik M, Buhmann MT, Yaghmur A, Ren Q, Maniura-Weber K, Salentinig S. Antimicrobial Peptide-Driven Colloidal Transformations in Liquid-Crystalline Nanocarriers. J Phys Chem Lett 2016; 7:3482-3486. [PMID: 27541048 DOI: 10.1021/acs.jpclett.6b01622] [Citation(s) in RCA: 61] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
Designing efficient colloidal systems for the delivery of membrane active antimicrobial peptides requires in-depth understanding of their structural and morphological characteristics. Using dispersions of inverted type bicontinuous cubic phase (cubosomes), we examine the effect of integrating the amphiphilic peptide LL-37 at different concentrations on the self-assembled structure and evaluate its bactericidal ability against Escherichia coli. Small-angle X-ray scattering, dynamic light scattering, and cryogenic transmission electron microscopy show that LL-37 integrates into the bicontinuous cubic structure, inducing colloidal transformations to sponge and lamellar phases and micelles in a concentration-dependent manner. These investigations, together with in vitro evaluation studies using a clinically relevant bacterial strain, established the composition-nanostructure-activity relationship that can guide the design of new nanocarriers for antimicrobial peptides and may provide essential knowledge on the mechanisms underlying the bacterial membrane disruption with peptide-loaded nanostructures.
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Affiliation(s)
- Mark Gontsarik
- Laboratory for Biointerfaces, Department Materials meet Life, Empa, Swiss Federal Laboratories for Materials Science and Technology , Lerchenfeldstrasse 5, 9014 St. Gallen, Switzerland
- Department of Pharmacy, Faculty of Health and Medical Sciences, University of Copenhagen , Universitetsparken 2, DK-2100 Copenhagen Ø, Denmark
| | - Matthias T Buhmann
- Laboratory for Biointerfaces, Department Materials meet Life, Empa, Swiss Federal Laboratories for Materials Science and Technology , Lerchenfeldstrasse 5, 9014 St. Gallen, Switzerland
| | - Anan Yaghmur
- Department of Pharmacy, Faculty of Health and Medical Sciences, University of Copenhagen , Universitetsparken 2, DK-2100 Copenhagen Ø, Denmark
| | - Qun Ren
- Laboratory for Biointerfaces, Department Materials meet Life, Empa, Swiss Federal Laboratories for Materials Science and Technology , Lerchenfeldstrasse 5, 9014 St. Gallen, Switzerland
| | - Katharina Maniura-Weber
- Laboratory for Biointerfaces, Department Materials meet Life, Empa, Swiss Federal Laboratories for Materials Science and Technology , Lerchenfeldstrasse 5, 9014 St. Gallen, Switzerland
| | - Stefan Salentinig
- Laboratory for Biointerfaces, Department Materials meet Life, Empa, Swiss Federal Laboratories for Materials Science and Technology , Lerchenfeldstrasse 5, 9014 St. Gallen, Switzerland
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48
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Rao J, Zhang H, Gaan S, Salentinig S. Self-Assembly of Polystyrene-b-poly(2-vinylpyridine) Micelles: From Solutions to Silica Particles Surfaces. Macromolecules 2016. [DOI: 10.1021/acs.macromol.6b01074] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Jingyi Rao
- Department Materials meet
Life, Empa, Swiss Federal Laboratories for Materials Science and Technology, Lerchenfeldstrasse 5, 9014, St. Gallen, Switzerland
| | - Haijiang Zhang
- Department Materials meet
Life, Empa, Swiss Federal Laboratories for Materials Science and Technology, Lerchenfeldstrasse 5, 9014, St. Gallen, Switzerland
| | - Sabyasachi Gaan
- Department Materials meet
Life, Empa, Swiss Federal Laboratories for Materials Science and Technology, Lerchenfeldstrasse 5, 9014, St. Gallen, Switzerland
| | - Stefan Salentinig
- Department Materials meet
Life, Empa, Swiss Federal Laboratories for Materials Science and Technology, Lerchenfeldstrasse 5, 9014, St. Gallen, Switzerland
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49
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Cipolla D, Wu H, Salentinig S, Boyd B, Rades T, Vanhecke D, Petri-Fink A, Rothin-Rutishauser B, Eastman S, Redelmeier T, Gonda I, Chan HK. Formation of drug nanocrystals under nanoconfinement afforded by liposomes. RSC Adv 2016. [DOI: 10.1039/c5ra25898g] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
In response to freeze–thaw, liposome-encapsulated antibiotic (A) is converted into nanocrystalline form (B) resulting in an attenuated drug release profile.
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Affiliation(s)
- D. Cipolla
- Faculty of Pharmacy
- The University of Sydney
- Australia
- Aradigm Corporation
- Hayward
| | - H. Wu
- Aradigm Corporation
- Hayward
- USA
| | - S. Salentinig
- Laboratory for Biointerfaces, Department Materials meet Life, Empa
- Swiss Federal Laboratories for Materials Science and Technology
- St. Gallen
- Switzerland
| | - B. Boyd
- Monash Institute of Pharmaceutical Sciences
- Monash
- Australia
| | - T. Rades
- Department of Pharmaceutical Sciences
- University of Copenhagen
- Denmark
| | - D. Vanhecke
- Adolphe Merkle Institute
- Université de Fribourg
- Fribourg
- Switzerland
| | - A. Petri-Fink
- Adolphe Merkle Institute
- Université de Fribourg
- Fribourg
- Switzerland
| | | | | | | | | | - H. K. Chan
- Faculty of Pharmacy
- The University of Sydney
- Australia
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50
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Cipolla D, Wu H, Salentinig S, Boyd B, Rades T, Vanhecke D, Petri-Fink A, Rothen-Rutishauser B, Eastman S, Redelmeier T, Gonda I, Chan HK. Correction: Formation of drug nanocrystals under nanoconfinement afforded by liposomes. RSC Adv 2016. [DOI: 10.1039/c6ra90006b] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
Correction for ‘Formation of drug nanocrystals under nanoconfinement afforded by liposomes’ by D. Cipolla et al., RSC Adv., 2016, 6, 6223–6233.
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Affiliation(s)
- D. Cipolla
- Faculty of Pharmacy
- The University of Sydney
- Australia
- Aradigm Corporation
- Hayward
| | - H. Wu
- Aradigm Corporation
- Hayward
- USA
| | - S. Salentinig
- Laboratory for Biointerfaces
- Department Materials meet Life
- Empa
- Swiss Federal Laboratories for Materials Science and Technology
- St. Gallen
| | - B. Boyd
- Monash Institute of Pharmaceutical Sciences
- Monash
- Australia
| | - T. Rades
- Department of Pharmaceutical Sciences
- University of Copenhagen
- Denmark
| | - D. Vanhecke
- Adolphe Merkle Institute
- Université de Fribourg
- Fribourg
- Switzerland
| | - A. Petri-Fink
- Adolphe Merkle Institute
- Université de Fribourg
- Fribourg
- Switzerland
| | | | | | | | | | - H. K. Chan
- Faculty of Pharmacy
- The University of Sydney
- Australia
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