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Abdelmoneim D, Coates D, Porter G, Schmidlin P, Li KC, Botter S, Lim K, Duncan W. In vitro and in vivo investigation of antibacterial silver nanoparticles functionalized bone grafting substitutes. J Biomed Mater Res A 2024. [PMID: 38864151 DOI: 10.1002/jbm.a.37757] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2023] [Revised: 05/15/2024] [Accepted: 05/20/2024] [Indexed: 06/13/2024]
Abstract
Infection is a major concern in surgery involving grafting and should be considered thoroughly when designing biomaterials. There is considerable renewed interest in silver nanoparticles (AgNPs) owing to their ability to potentiate antibacterial properties against multiple bacterial strains. This study aimed to develop two antibacterial bone regenerative scaffolds by integrating AgNPs in bovine bone particles (BBX) (Product 1), and a light cross-linked hydrogel GelMA (Product 2). The constructs were characterized using scanning electron microscopy. Metabolic activity of osteoblasts and osteoclasts on the constructs was investigated using PrestoBlue™. Disk diffusion assay was conducted to test the antibacterial properties. The regenerative capacity of the optimized AgNP functionalized BBX and GelMA were tested in a rabbit cranial 6 mm defect model. The presence of AgNPs appears to enhance proliferation of osteoblasts compared to AgNP free controls in vitro. We established that AgNPs can be used at a 100 μg dose that inhibits bacteria, with minimal adverse effects on the bone cells. Our rabbit model revealed that both the BBX and GelMA hydrogels loaded AgNPs were biocompatible with no signs of necrosis or inflammatory response. Grafts functionalized with AgNPs can provide antibacterial protection and simultaneously act as a scaffold for attachment of bone cells.
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Affiliation(s)
- Dina Abdelmoneim
- Sir John Walsh Research Institute, Faculty of Dentistry, University of Otago, Dunedin, New Zealand
| | - Dawn Coates
- Sir John Walsh Research Institute, Faculty of Dentistry, University of Otago, Dunedin, New Zealand
| | - Gemma Porter
- Sir John Walsh Research Institute, Faculty of Dentistry, University of Otago, Dunedin, New Zealand
| | - Patrick Schmidlin
- Clinic of Conservative and Preventive Dentistry, Center of Dental Medicine, University of Zurich, Zurich, Switzerland
| | - Kai Chun Li
- Sir John Walsh Research Institute, Faculty of Dentistry, University of Otago, Dunedin, New Zealand
| | - Sander Botter
- Swiss Center for Musculoskeletal Biobanking, Balgrist Campus AG, Zurich, Switzerland
| | - Khoon Lim
- Christchurch Regenerative Medicine and Tissue Engineering (CReaTE) group, Department of Orthopaedic Surgery and Musculoskeletal Medicine, University of Otago, Christchurch, New Zealand
| | - Warwick Duncan
- Sir John Walsh Research Institute, Faculty of Dentistry, University of Otago, Dunedin, New Zealand
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2
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Bellini C, Mancin F, Papini E, Tavano R. Nanotechnological Approaches to Enhance the Potential of α-Lipoic Acid for Application in the Clinic. Antioxidants (Basel) 2024; 13:706. [PMID: 38929145 PMCID: PMC11201002 DOI: 10.3390/antiox13060706] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2024] [Revised: 05/30/2024] [Accepted: 06/04/2024] [Indexed: 06/28/2024] Open
Abstract
α-lipoic acid is a naturally occurring compound with potent antioxidant properties that helps protect cells and tissues from oxidative stress. Its incorporation into nanoplatforms can affect factors like bioavailability, stability, reactivity, and targeted delivery. Nanoformulations of α-lipoic acid can significantly enhance its solubility and absorption, making it more bioavailable. While α-lipoic acid can be prone to degradation in its free form, encapsulation within nanoparticles ensures its stability over time, and its release in a controlled and sustained manner to the targeted tissues and cells. In addition, α-lipoic acid can be combined with other compounds, such as other antioxidants, drugs, or nanomaterials, to create synergistic effects that enhance their overall therapeutic benefits or hinder their potential cytotoxicity. This review outlines the advantages and drawbacks associated with the use of α-lipoic acid, as well as various nanotechnological approaches employed to enhance its therapeutic effectiveness, whether alone or in combination with other bioactive agents. Furthermore, it describes the engineering of α-lipoic acid to produce poly(α-lipoic acid) nanoparticles, which hold promise as an effective drug delivery system.
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Affiliation(s)
- Chiara Bellini
- Department of Biomedical Sciences, University of Padova, Via U. Bassi 58/b, 35121 Padova, Italy; (C.B.); (E.P.)
| | - Fabrizio Mancin
- Department of Chemical Sciences, University of Padova, Via F. Marzolo 1, 35121 Padova, Italy;
| | - Emanuele Papini
- Department of Biomedical Sciences, University of Padova, Via U. Bassi 58/b, 35121 Padova, Italy; (C.B.); (E.P.)
| | - Regina Tavano
- Department of Biomedical Sciences, University of Padova, Via U. Bassi 58/b, 35121 Padova, Italy; (C.B.); (E.P.)
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3
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Martínez-García K, Zertuche-Arias T, Bernáldez-Sarabia J, Iñiguez E, Kretzchmar T, Camacho-Villegas TA, Lugo-Fabres PH, Licea Navarro AF, Bravo-Madrigal J, Castro-Ceseña AB. Radical Scavenging, Hemocompatibility, and Antibacterial Activity against MDR Acinetobacter baumannii in Alginate-Based Aerogels Containing Lipoic Acid-Capped Silver Nanoparticles. ACS OMEGA 2024; 9:2350-2361. [PMID: 38250422 PMCID: PMC10795026 DOI: 10.1021/acsomega.3c06114] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/23/2023] [Revised: 12/21/2023] [Accepted: 12/25/2023] [Indexed: 01/23/2024]
Abstract
Retaining the hemocompatibility, supporting cell growth, and exhibiting anti-inflammatory and antioxidant properties, while having antimicrobial activity, particularly against multidrug-resistant bacteria (MDR), remain a challenge when designing aerogels for biomedical applications. Here, we report that our synthesized alginate-based aerogels containing either 7.5 or 11.25 μg of lipoic acid-capped silver nanoparticles (AgNPs) showed improved hemocompatibility properties while retaining their antimicrobial effect against MDR Acinetobacter baumannii and the reference strain Escherichia coli, relative to a commercial dressing and polymyxin B, used as a reference. The differences in terms of the microstructure and nature of the silver, used as the bioactive agent, between our synthesized aerogels and the commercial dressing used as a reference allowed us to improve several biological properties in our aerogels with respect to the reference commercial material. Our aerogels showed significantly higher antioxidant capacity, in terms of nmol of Trolox equivalent antioxidant capacity per mg of aerogel, than the commercial dressing. All our synthesized aerogels showed anti-inflammatory activity, expressed as nmol of indomethacin equivalent anti-inflammatory activity per mg of aerogel, while this property was not found in the commercial dressing material. Finally, our aerogels were highly hemocompatible (less than 1% hemolysis ratio); however, the commercial material showed a 20% hemolysis rate. Therefore, our alginate-based aerogels with lipoic acid-capped AgNPs hold promise for biomedical applications.
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Affiliation(s)
- Kevin
D. Martínez-García
- Departamento
de Innovación Biomédica, Centro
de Investigación Científica y de Educación Superior
de Ensenada, Baja California (CICESE), Carretera Ensenada-Tijuana No. 3918, Zona Playitas, C.P. 22860 Ensenada, Baja California, Mexico
| | - Tonatzin Zertuche-Arias
- Departamento
de Innovación Biomédica, Centro
de Investigación Científica y de Educación Superior
de Ensenada, Baja California (CICESE), Carretera Ensenada-Tijuana No. 3918, Zona Playitas, C.P. 22860 Ensenada, Baja California, Mexico
| | - Johanna Bernáldez-Sarabia
- Departamento
de Innovación Biomédica, Centro
de Investigación Científica y de Educación Superior
de Ensenada, Baja California (CICESE), Carretera Ensenada-Tijuana No. 3918, Zona Playitas, C.P. 22860 Ensenada, Baja California, Mexico
| | - Enrique Iñiguez
- Ciencias
de la Tierra, Centro de Investigación
Científica y de Educación Superior de Ensenada, Baja
California (CICESE), Carretera Ensenada-Tijuana No. 3918, Zona Playitas, C.P. 22860 Ensenada, Baja California, Mexico
- CONAHCYT—Ciencias
de la Tierra, Centro de Investigación
Científica y de Educación Superior de Ensenada, Baja
California (CICESE), Carretera Ensenada-Tijuana No. 3918, Zona Playitas, C.P. 22860 Ensenada, Baja California, Mexico
| | - Thomas Kretzchmar
- Ciencias
de la Tierra, Centro de Investigación
Científica y de Educación Superior de Ensenada, Baja
California (CICESE), Carretera Ensenada-Tijuana No. 3918, Zona Playitas, C.P. 22860 Ensenada, Baja California, Mexico
| | - Tanya Amanda Camacho-Villegas
- Unidad
de Biotecnología Médica y Farmacéutica, Centro de Investigación Asistencia en Tecnología
y Diseño de Estado de Jalisco (CIATEJ), A.C. Av. Normalistas No. 800, Colinas de la Normal, C.P. 44270 Guadalajara, Jalisco, Mexico
- CONAHCYT-Unidad
de Biotecnología Médica y Farmacéutica, Centro de Investigación Asistencia en Tecnología
y Diseño del Estado de Jalisco (CIATEJ), A.C. Av. Normalistas No. 800, Colinas de la Normal, C.P. 44270 Guadalajara, Jalisco, Mexico
| | - Pavel H. Lugo-Fabres
- Unidad
de Biotecnología Médica y Farmacéutica, Centro de Investigación Asistencia en Tecnología
y Diseño de Estado de Jalisco (CIATEJ), A.C. Av. Normalistas No. 800, Colinas de la Normal, C.P. 44270 Guadalajara, Jalisco, Mexico
- CONAHCYT-Unidad
de Biotecnología Médica y Farmacéutica, Centro de Investigación Asistencia en Tecnología
y Diseño del Estado de Jalisco (CIATEJ), A.C. Av. Normalistas No. 800, Colinas de la Normal, C.P. 44270 Guadalajara, Jalisco, Mexico
| | - Alexei F. Licea Navarro
- Departamento
de Innovación Biomédica, Centro
de Investigación Científica y de Educación Superior
de Ensenada, Baja California (CICESE), Carretera Ensenada-Tijuana No. 3918, Zona Playitas, C.P. 22860 Ensenada, Baja California, Mexico
| | - Jorge Bravo-Madrigal
- Unidad
de Biotecnología Médica y Farmacéutica, Centro de Investigación Asistencia en Tecnología
y Diseño de Estado de Jalisco (CIATEJ), A.C. Av. Normalistas No. 800, Colinas de la Normal, C.P. 44270 Guadalajara, Jalisco, Mexico
| | - Ana B. Castro-Ceseña
- Departamento
de Innovación Biomédica, Centro
de Investigación Científica y de Educación Superior
de Ensenada, Baja California (CICESE), Carretera Ensenada-Tijuana No. 3918, Zona Playitas, C.P. 22860 Ensenada, Baja California, Mexico
- CONAHCYT-Departamento
de Innovación Biomédica, Centro
de Investigación Científica y de Educación Superior
de Ensenada, Baja California (CICESE), Carretera Ensenada-Tijuana No. 3918, Zona Playitas, C.P. 22860 Ensenada, Baja California, Mexico
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4
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Fontoura I, Veriato TS, Raniero LJ, Castilho ML. Analysis of Capped Silver Nanoparticles Combined with Imipenem against Different Susceptibility Profiles of Klebsiella pneumoniae. Antibiotics (Basel) 2023; 12:antibiotics12030535. [PMID: 36978403 PMCID: PMC10044117 DOI: 10.3390/antibiotics12030535] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2022] [Revised: 11/18/2022] [Accepted: 11/22/2022] [Indexed: 03/10/2023] Open
Abstract
Klebsiella pneumoniae (K. pneumoniae) is an opportunistic bacterium that has drawn attention due to its resistance to carbapenem antibiotics. The treatment of patients with severe infections has been challenging. Thus, silver nanoparticles (AgNPs) have been applied for their antimicrobial effects. This work aims to analyze the synergistic effect of the carbapenem antibiotic Imipenem with AgNPs against different susceptibility clinical profiles of K. pneumoniae. The silver nanoparticles were synthesized by bottom-up methodology and capped with alpha-lipoic acid. Susceptibility tests were performed using four K. pneumoniae strains with different susceptibility profiles to Imipenem. The strains were induced to form a biofilm for 48 h. Crystal violet and Resazurin assays were performed to determine biofilm formation and minimal inhibitory concentration, respectively. The reduction in Imipenem concentration with the association of nanoparticles was found in all strains studied in planktonic form, and the synergism between silver nanoparticles and Imipenem was demonstrated through the analysis of the fractional inhibitory concentration index. The viability percentage was reduced at rates ≥80% in the biofilm analysis, characterized by the minimal biofilm inhibitory concentration. The study’s proposed association resulted in inhibitory effects on different K. pneumoniae profiles, both in planktonic forms and biofilm, with peculiar behavior in the Imipenem-resistant profile.
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Affiliation(s)
- Inglid Fontoura
- Bionanotechnology Laboratory, Research and Development Institute, University of Paraiba Valley, São José dos Campos 12244-000, SP, Brazil
| | - Thaís S. Veriato
- Bionanotechnology Laboratory, Research and Development Institute, University of Paraiba Valley, São José dos Campos 12244-000, SP, Brazil
| | - Leandro J. Raniero
- Nanosensors Laboratory, Research and Development Institute, University of Paraiba Valley, São José dos Campos 12244-000, SP, Brazil
| | - Maiara L. Castilho
- Bionanotechnology Laboratory, Research and Development Institute, University of Paraiba Valley, São José dos Campos 12244-000, SP, Brazil
- Correspondence: ; Tel.: +55-12-39471108
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5
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Abdelmoneim D, Porter G, Duncan W, Lim K, Easingwood R, Woodfield T, Coates D. Three-Dimensional Evaluation of the Cytotoxicity and Antibacterial Properties of Alpha Lipoic Acid-Capped Silver Nanoparticle Constructs for Oral Applications. NANOMATERIALS (BASEL, SWITZERLAND) 2023; 13:705. [PMID: 36839073 PMCID: PMC9958703 DOI: 10.3390/nano13040705] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 01/18/2023] [Revised: 02/05/2023] [Accepted: 02/08/2023] [Indexed: 06/18/2023]
Abstract
There is a need to develop bifunctional scaffolds that provide antibacterial protection while encouraging host cell attachment/proliferation. This study evaluates HyStem®-C, and photo-cross-linked GelMA hydrogels for encapsulation and stabilisation of silver nanoparticles (AgNPs). We studied the behaviour of AgNPs and matrix interactions within both hydrogel systems. The cell viability of encapsulated human gingival fibroblasts (HGFs) was determined by Prestoblue® assay and live/dead staining. The release of AgNPs was monitored by inductively coupled plasma-mass spectroscopy. The antibacterial properties of the GelMA-AgNP constructs were determined using disc diffusion. Even distribution of AgNPs in GelMA induced a significant decrease in cell viability (p < 0.0001), whereas AgNP aggregates did not induce cytotoxicity in HyStem®-C. AgNPs doses ≥ 0.5 µg/mL in GelMA were significantly toxic to the HGFs (p < 0.0001). The release of AgNPs from GelMA after 48 h was 20% w/w for 0.1 µg/mL and 51% for 100 µg/mL of AgNPs. At ≥5 µg/mL, a significant intra-construct bactericidal effect was observed. The disc diffusion assay shows that GelMA-incorporated AgNPs were found to be effective against both Escherichia coli and Staphylococcus aureus at 50 and 100 µg/mL, respectively. Visible photo-cross-linked GelMA stably incorporated AgNPs to provide an antimicrobial regenerative construct for oral applications.
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Affiliation(s)
- Dina Abdelmoneim
- Sir John Walsh Research Institute, Faculty of Dentistry, University of Otago, Dunedin 9010, New Zealand
| | - Gemma Porter
- Sir John Walsh Research Institute, Faculty of Dentistry, University of Otago, Dunedin 9010, New Zealand
| | - Warwick Duncan
- Sir John Walsh Research Institute, Faculty of Dentistry, University of Otago, Dunedin 9010, New Zealand
| | - Khoon Lim
- Christchurch Regenerative Medicine and Tissue Engineering (CReaTE) Group, Department of Orthopaedic Surgery and Musculoskeletal Medicine, University of Otago, Christchurch 8011, New Zealand
| | - Richard Easingwood
- Otago Micro and Nanoscale Imaging, Department of Anatomy, University of Otago, Dunedin 9016, New Zealand
| | - Tim Woodfield
- Christchurch Regenerative Medicine and Tissue Engineering (CReaTE) Group, Department of Orthopaedic Surgery and Musculoskeletal Medicine, University of Otago, Christchurch 8011, New Zealand
| | - Dawn Coates
- Sir John Walsh Research Institute, Faculty of Dentistry, University of Otago, Dunedin 9010, New Zealand
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6
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Suvarli N, Frentzel M, Hubbuch J, Perner-Nochta I, Wörner M. Synthesis of Spherical Nanoparticle Hybrids via Aerosol Thiol-Ene Photopolymerization and Their Bioconjugation. NANOMATERIALS 2022; 12:nano12030577. [PMID: 35159922 PMCID: PMC8838805 DOI: 10.3390/nano12030577] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/19/2022] [Revised: 02/02/2022] [Accepted: 02/05/2022] [Indexed: 12/04/2022]
Abstract
Hybrid nanomaterials possess the properties of both organic and inorganic components and find applications in various fields of research and technology. In this study, aerosol photopolymerization is used in combination with thiol-ene chemistry to produce silver poly(thio-ether) hybrid nanospheres. In aerosol photopolymerization, a spray solution of monomers is atomized, forming a droplet aerosol, which then polymerizes, producing spherical polymer nanoparticles. To produce silver poly(thio-ether) hybrids, silver nanoparticles were introduced to the spray solution. Diverse methods of stabilization were used to produce stable dispersions of silver nanoparticles to prevent their agglomeration before the photopolymerization process. Successfully stabilized silver nanoparticle dispersion in the spray solution subsequently formed nanocomposites with non-agglomerated silver nanoparticles inside the polymer matrix. Nanocomposite particles were analyzed via scanning and transmission electron microscopy to study the degree of agglomeration of silver nanoparticles and their location inside the polymer spheres. The nanoparticle hybrids were then introduced onto various biofunctionalization reactions. A two-step bioconjugation process was developed involving the hybrid nanoparticles: (1) conjugation of (biotin)-maleimide to thiol-groups on the polymer network of the hybrids, and (2) biotin-streptavidin binding. The biofunctionalization with gold-nanoparticle-conjugates was carried out to confirm the reactivity of -SH groups on each conjugation step. Fluorescence-labeled biomolecules were conjugated to the spherical nanoparticle hybrids (applying the two-step bioconjugation process) verified by Fluorescence Spectroscopy and Fluorescence Microscopy. The presented research offers an effective method of synthesis of smart systems that can further be used in biosensors and various other biomedical applications.
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7
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Hajtuch J, Santos-Martinez MJ, Wojcik M, Tomczyk E, Jaskiewicz M, Kamysz W, Narajczyk M, Inkielewicz-Stepniak I. Lipoic Acid-Coated Silver Nanoparticles: Biosafety Potential on the Vascular Microenvironment and Antibacterial Properties. Front Pharmacol 2022; 12:733743. [PMID: 35153735 PMCID: PMC8831385 DOI: 10.3389/fphar.2021.733743] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2021] [Accepted: 11/26/2021] [Indexed: 12/04/2022] Open
Abstract
Purpose: To study and compare the antibacterial properties and the potential cytotoxic effects of commercially available uncoated silver nanoparticles (AgNPs) with lipoic acid coated silver nanoparticles (AgNPsLA) developed by our group. The antibacterial, cytotoxic, and hemolytic properties of those NPs were assessed with the main objective of investigating if AgNPsLA could maintain their antibacterial properties while improving their biosafety profile over uncoated AgNPs within the blood vessel’s microenvironment. Methods: Comercially available uncoated 2.6 nm AgNPs and 2.5 nm AgNPsLA synthesized and characterized as previously described by our group, were used in this study. Antimicrobial activity was assessed on a wide range of pathogens and expressed by minimal inhibitory concentrations (MIC). Assessment of cytotoxicity was carried out on human umbilical vein endothelial cells (HUVEC) using an MTT test. Detection of reactive oxygen species, cell apoptosis/necrosis in HUVEC, and measurement of mitochondrial destabilization in HUVEC and platelets were performed by flow cytometry. The potential harmful effect of nanoparticles on red blood cells (RBCs) was investigated measuring hemoglobin and LDH released after exposure to NPs. Transmission electron microscopy was also used to determine if AgNPs and AgNPsLA could induce any ultrastructural changes on HUVEC cells and Staphylococcus aureus bacteria. Results: AgNPs and AgNPsLA had antimicrobial properties against pathogens associated with catheter-related bloodstream infections. AgNPs, in contrast to AgNPsLA, induced ROS production and apoptosis in HUVEC, ultrastructural changes in HUVEC and S. aureus, depolarization of mitochondrial membrane in HUVEC and platelets, and also hemolysis. Conclusion: AgNPsLA synthesized by our group have antimicrobial activity and a better biosafety profile than uncoated AgNPs of similar size. Those observations are of critical importance for the future in vivo investigations and the potential application of AgNPsLA in medical devices for human use.
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Affiliation(s)
- Justyna Hajtuch
- Department of Pharmaceutical Pathophysiology, Medical University of Gdansk, Gdansk, Poland
| | - Maria Jose Santos-Martinez
- School of Pharmacy and Pharmaceutical Sciences and School of Medicine, Trinity Biomedical Sciences Institute, Trinity College Dublin, Dublin, Ireland
| | - Michal Wojcik
- Department of Organic Chemistry and Chemical Technology, Faculty of Chemistry, University of Warsaw, Warsaw, Poland
| | - Ewelina Tomczyk
- Department of Organic Chemistry and Chemical Technology, Faculty of Chemistry, University of Warsaw, Warsaw, Poland
| | - Maciej Jaskiewicz
- Department of Inorganic Chemistry, Faculty of Pharmacy, Medical University of Gdansk, Gdansk, Poland
| | - Wojciech Kamysz
- Department of Inorganic Chemistry, Faculty of Pharmacy, Medical University of Gdansk, Gdansk, Poland
| | - Magdalena Narajczyk
- Laboratory of Electron Microscopy, Faculty of Biology, University of Gdansk, Gdansk, Poland
| | - Iwona Inkielewicz-Stepniak
- Department of Pharmaceutical Pathophysiology, Medical University of Gdansk, Gdansk, Poland
- *Correspondence: Iwona Inkielewicz-Stepniak,
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Duncan WJ, Coates DE. Meeting the challenges and clinical requirements for dental regeneration; the New Zealand experience. Bone 2022; 154:116181. [PMID: 34509689 DOI: 10.1016/j.bone.2021.116181] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/08/2021] [Revised: 09/05/2021] [Accepted: 09/06/2021] [Indexed: 11/02/2022]
Abstract
Disease and trauma leading to tooth loss and destruction of supporting bone is a significant oral handicap, which may be addressed through surgical therapies that aim to regenerate the lost tissue. Whilst complete regeneration of teeth is still aspirational, regeneration of supporting structures (dental pulp, cementum, periodontal ligament, bone) is becoming commonplace, both for teeth and for titanium dental implants that are used to replace teeth. Most grafting materials are essentially passive, however the next generation of oral regenerative devices will combine non-antibiotic antimicrobials and/or osteogenic or inductive factors and/or appropriate multipotential stem cells. The review gives an overview of the approaches taken, including fabrication of novel scaffolds, incorporation of growth factors and cell-based therapies, and discusses the preclinical animal models we employ in the development pathway.
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Affiliation(s)
- Warwick J Duncan
- Sir John Walsh Research Institute, Faculty of Dentistry, University of Otago, Dunedin, New Zealand.
| | - Dawn E Coates
- Sir John Walsh Research Institute, Faculty of Dentistry, University of Otago, Dunedin, New Zealand.
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An X, Liu L, Schaefer M, Yan B, Scholz C, Hillmer S, Wang K, Luo Y, Ji H, Gladkich J, Herr I. Alpha-Lipoic Acid Prevents Side Effects of Therapeutic Nanosilver without Compromising Cytotoxicity in Experimental Pancreatic Cancer. Cancers (Basel) 2021; 13:4770. [PMID: 34638256 PMCID: PMC8507678 DOI: 10.3390/cancers13194770] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2021] [Revised: 09/16/2021] [Accepted: 09/20/2021] [Indexed: 01/14/2023] Open
Abstract
Silver nanoparticles (AgNPs) have attracted attention in cancer therapy and might support the treatment of pancreatic ductal adenocarcinoma (PDAC). Silver is in clinical use in wound dressings, catheters, stents and implants. However, the side effects of systemic AgNP treatment due to silver accumulation limit its therapeutic application. We evaluated whether the antioxidant and natural agent α-lipoic acid might prevent these side effects. We synthesized AgNPs using an Ionic-Pulser® Pro silver generator and determined the concentration by inductively coupled plasma-optical emission spectrometry. The effect of α-lipoic acid was examined in four PDAC and two nonmalignant cell lines by MTT, FACS analysis, TEM, xenotransplantation and immunohistochemistry. The viability of PDAC cells was nearly totally abolished by AgNP treatment, whereas nonmalignant cells largely resisted. α-Lipoic acid prevented AgNP-induced cytotoxicity in nonmalignant cells but not in PDAC cells, which might be due to the higher sensitivity of malignant cells to silver-induced cytotoxicity. α-Lipoic acid protected mitochondria from AgNP-induced damage and led to precipitation of AgNPs. AgNPs reduced the growth of tumor xenografts, and cotreatment with α-lipoic acid protected chick embryos from AgNP-induced liver damage. Together, α-lipoic acid strongly reduced AgNP-induced side effects without weakening the therapeutic efficacy.
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Affiliation(s)
- Xuefeng An
- Department of General, Visceral & Transplant Surgery, Molecular OncoSurgery, Section Surgical Research, University of Heidelberg, 69120 Heidelberg, Germany; (X.A.); (L.L.); (M.S.); (B.Y.); (K.W.); (Y.L.); (H.J.); (J.G.)
| | - Li Liu
- Department of General, Visceral & Transplant Surgery, Molecular OncoSurgery, Section Surgical Research, University of Heidelberg, 69120 Heidelberg, Germany; (X.A.); (L.L.); (M.S.); (B.Y.); (K.W.); (Y.L.); (H.J.); (J.G.)
| | - Michael Schaefer
- Department of General, Visceral & Transplant Surgery, Molecular OncoSurgery, Section Surgical Research, University of Heidelberg, 69120 Heidelberg, Germany; (X.A.); (L.L.); (M.S.); (B.Y.); (K.W.); (Y.L.); (H.J.); (J.G.)
| | - Bin Yan
- Department of General, Visceral & Transplant Surgery, Molecular OncoSurgery, Section Surgical Research, University of Heidelberg, 69120 Heidelberg, Germany; (X.A.); (L.L.); (M.S.); (B.Y.); (K.W.); (Y.L.); (H.J.); (J.G.)
| | - Christian Scholz
- Institute of Earth Sciences, University of Heidelberg, 69120 Heidelberg, Germany;
| | - Stefan Hillmer
- Electron Microscopy Core Facility, University of Heidelberg, 69120 Heidelberg, Germany;
| | - Kangtao Wang
- Department of General, Visceral & Transplant Surgery, Molecular OncoSurgery, Section Surgical Research, University of Heidelberg, 69120 Heidelberg, Germany; (X.A.); (L.L.); (M.S.); (B.Y.); (K.W.); (Y.L.); (H.J.); (J.G.)
| | - Yiqiao Luo
- Department of General, Visceral & Transplant Surgery, Molecular OncoSurgery, Section Surgical Research, University of Heidelberg, 69120 Heidelberg, Germany; (X.A.); (L.L.); (M.S.); (B.Y.); (K.W.); (Y.L.); (H.J.); (J.G.)
| | - Huihui Ji
- Department of General, Visceral & Transplant Surgery, Molecular OncoSurgery, Section Surgical Research, University of Heidelberg, 69120 Heidelberg, Germany; (X.A.); (L.L.); (M.S.); (B.Y.); (K.W.); (Y.L.); (H.J.); (J.G.)
| | - Jury Gladkich
- Department of General, Visceral & Transplant Surgery, Molecular OncoSurgery, Section Surgical Research, University of Heidelberg, 69120 Heidelberg, Germany; (X.A.); (L.L.); (M.S.); (B.Y.); (K.W.); (Y.L.); (H.J.); (J.G.)
| | - Ingrid Herr
- Department of General, Visceral & Transplant Surgery, Molecular OncoSurgery, Section Surgical Research, University of Heidelberg, 69120 Heidelberg, Germany; (X.A.); (L.L.); (M.S.); (B.Y.); (K.W.); (Y.L.); (H.J.); (J.G.)
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Kollár J, Popelka A, Tkac J, Žabka M, Mosnáček J, Kasak P. Sulfobetaine-based polydisulfides with tunable upper critical solution temperature (UCST) in water alcohols mixture, depolymerization kinetics and surface wettability. J Colloid Interface Sci 2021; 588:196-208. [PMID: 33387822 DOI: 10.1016/j.jcis.2020.12.048] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2020] [Revised: 12/15/2020] [Accepted: 12/16/2020] [Indexed: 02/07/2023]
Abstract
HYPOTHESIS Synthesis of a new family of polymers having a polydisulfide structure can be conducted from sulfobetaine-based derivative of natural (R)-lipoic acid. A polydisulfide backbone of polymer can be depolymerized by response to external stimuli and sulfobetaine pendant groups ensure the upper critical solution temperature (UCST) behaviour temperatures that can be modulated according to the nature of the solvent and concentration. EXPERIMENTS Sulfobetaine-bearing polydisulfides were synthesized from dithiolane derivatives and then characterized. UCST behavior of the polymers in water and in mixtures containing different alcohols (methanol, ethanol, isopropanol) was investigated. The regeneration of monomers from the polymers in response to external stimuli was examined using UV-vis and circular dichroism (CD) spectroscopy. Tunable surface wettability were shown on the grafted polymers. FINDINGS Decreasing polarity and/or increasing alcohol percentage in the water mixtures induced an increase in the cloud points of the polymers in the solutions. Thermoresponsive behaviour were repeatable and fully reversible with negligible hysteresis from aggregate to unimer state. The regeneration of monomers by depolymerization was tunable by temperature and sunlight. A thickness dependence on surface wettability was observed on wafers covalently modified with polydisulfides. This is the first report of sulfobetaine-based polydisulfides showing tunable UCST behavior and surface wettability.
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Affiliation(s)
- Jozef Kollár
- Center for Advanced Materials, Qatar University, P.O. Box 2713, Doha, Qatar; Polymer Institute, Slovak Academy of Sciences, Dúbravská cesta 9, 845 41 Bratislava, Slovak Republic
| | - Anton Popelka
- Center for Advanced Materials, Qatar University, P.O. Box 2713, Doha, Qatar
| | - Jan Tkac
- Institute of Chemistry, Slovak Academy of Sciences, Dubravska cesta 9, Bratislava 845 38, Slovak Republic
| | - Matej Žabka
- Department of Organic Chemistry, Faculty of Natural Sciences, Comenius University in Bratislava, Mlynská dolina, Ilkovičova 6, 842 15 Bratislava, Slovak Republic
| | - Jaroslav Mosnáček
- Polymer Institute, Slovak Academy of Sciences, Dúbravská cesta 9, 845 41 Bratislava, Slovak Republic; Centre for Advanced Materials Application, Slovak Academy of Sciences, Dubravska cesta 9, 845 11 Bratislava, Slovak Republic
| | - Peter Kasak
- Center for Advanced Materials, Qatar University, P.O. Box 2713, Doha, Qatar.
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11
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Chong WX, Lai YX, Choudhury M, Amalraj FD. Efficacy of incorporating silver nanoparticles into maxillofacial silicone against Staphylococcus aureus, Candida albicans, and polymicrobial biofilms. J Prosthet Dent 2021; 128:1114-1120. [PMID: 33685653 DOI: 10.1016/j.prosdent.2021.01.010] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2019] [Revised: 01/24/2021] [Accepted: 01/25/2021] [Indexed: 10/22/2022]
Abstract
STATEMENT OF PROBLEM The presence of biofilms on maxillofacial silicone increases the risk of infections and reduces durability. Whether silver nanoparticles (AgNPs) with potent antimicrobial effects help reduce biofilm formation is unclear. PURPOSE The purpose of this in vitro study was to assess the antimicrobial effect of sub 10-nm AgNPs in maxillofacial silicone against Staphylococcus aureus, Candida albicans, and mixed species biofilms containing both and to test the effectiveness of different AgNP concentrations against all 3 biofilms in vitro. MATERIAL AND METHODS Silicone disks (M511; Technovent Ltd) containing 0.0% (control), 0.1%, and 0.5% AgNPs were fabricated and treated with S. aureus, C. albicans, and mixed species strains of both in 24-well culture plates containing appropriate media. Each well received a 0.1-mL aliquot of the standardized suspension of microorganisms. The plates were incubated for 21 consecutive days, and colony-forming units per milliliter (CFU/mL) were measured on the first, third, fifth, seventh, fifteenth, and twenty-first day with the Miles and Misra method. Data were analyzed by 2-way ANOVA and the paired t test to evaluate the relationship between AgNP concentration, microbial strain, and time (α=.05). Mean CFU/mL differences for each time and for each biofilm category were assessed by repeated measure ANOVA. RESULTS AgNPs decreased the mean CFU/mL in both concentrations compared with the control. The 0.1% concentration showed sustained efficacy throughout the test, while the 0.5% concentration had high efficacy initially with a gradual decrease. However, the results were inconsistent for the mixed biofilm. The paired sample t test at day 3 and 15 and day 3 and 21 showed statistically significantly different results (P<.001) in all but 1 group in the 0.5% concentration. The 2-way mixed ANOVA showed statistically significant (P<.001) interaction between AgNP concentration and time in all groups. The 1-way ANOVA of AgNP concentrations was statistically significantly different (P<.001) for all time points. A statistically significant (P<.001) effect of time on CFU/mL was found for all the AgNP concentration groups in all 3 biofilms. CONCLUSIONS Silicone elastomers with sub 10-nm AgNPs displayed antimicrobial properties in vitro against S. aureus, C. albicans, and mixed species strains. AgNPs (0.1%) were effective against both microbial strains and can provide a baseline for further long-term studies regarding antimicrobial efficacy, silver ion leaching, and cellular internalization. Mixed species biofilm needs further exploration with standardized study parameters.
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Affiliation(s)
- Wen Xin Chong
- Graduate student, School of Dentistry, International Medical University, Kuala Lumpur, Malaysia
| | - Yee Xuan Lai
- Graduate student, School of Dentistry, International Medical University, Kuala Lumpur, Malaysia
| | - Minati Choudhury
- Senior Lecturer, Clinical Dentistry, International Medical University, Kuala Lumpur, Malaysia.
| | - Fabian Davamani Amalraj
- Senior Lecturer, Division of Applied Biomedical Science and Biotechnology, School of Health Sciences, International Medical University, Kuala Lumpur, Malaysia
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12
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Porter GC, Duncan WJ, Jude A, Abdelmoneim D, Easingwood RA, Coates DE. Endocytosed silver nanoparticles degrade in lysosomes to form secondary nanoparticle structures during expression of autophagy genes in osteogenic cells. NANOMEDICINE-NANOTECHNOLOGY BIOLOGY AND MEDICINE 2021; 33:102355. [PMID: 33454429 DOI: 10.1016/j.nano.2020.102355] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/20/2020] [Revised: 12/05/2020] [Accepted: 12/23/2020] [Indexed: 01/01/2023]
Abstract
Silver nanoparticles (AgNPs) are increasingly used in combination with biomaterials, such as bone grafts, to provide antimicrobial properties. Our research focused on the cytotoxic and intracellular uptake mechanism of AgNPs on osteogenic cells, and the affected gene expression of osteoblasts exposed to AgNPs. Osteoblast cells were found to be relatively resistant to AgNP exposure, compared to osteoclasts, with a higher IC50 and fewer adverse morphological features. AgNPs were endocytosed within lysosomes, which resulted in the secondary internal formation of curved AgO nano-chains assemblies within the cytosol. Furthermore, osteoblasts demonstrated an oxidative stress response, with autophagic cell death mechanisms, as indicated from qRT2-PCR analysis, with sustained upregulation of the protective gene Heme Oxygenase 1 reaching 86-fold by 48 hours (10 μg/mL). The internalization and fate of AgNPs in osteogenic cells, and the resulting impact on gene expression over time provide further understanding of the nanotoxicity mechanism of AgNPs.
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Affiliation(s)
- G C Porter
- Sir John Walsh Research Institute, Faculty of Dentistry, University of Otago, Dunedin, New Zealand.
| | - W J Duncan
- Sir John Walsh Research Institute, Faculty of Dentistry, University of Otago, Dunedin, New Zealand
| | - A Jude
- Sir John Walsh Research Institute, Faculty of Dentistry, University of Otago, Dunedin, New Zealand
| | - D Abdelmoneim
- Sir John Walsh Research Institute, Faculty of Dentistry, University of Otago, Dunedin, New Zealand
| | - R A Easingwood
- Otago Micro and Nanoscale Imaging, Department of Anatomy, University of Otago, Dunedin, New Zealand
| | - D E Coates
- Sir John Walsh Research Institute, Faculty of Dentistry, University of Otago, Dunedin, New Zealand
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13
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Li D, Kumari B, Makabenta JM, Tao B, Qian K, Mei X, Rotello VM. Development of coinage metal nanoclusters as antimicrobials to combat bacterial infections. J Mater Chem B 2020; 8:9466-9480. [PMID: 32955539 PMCID: PMC7606613 DOI: 10.1039/d0tb00549e] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
Infections from antibiotic-resistant bacteria have caused huge economic loss and numerous deaths over the past decades. Researchers are exploring multiple strategies to combat these bacterial infections. Metal nanomaterials have been explored as therapeutics against these infections owing to their relatively low toxicity, broad-spectrum activity, and low bacterial resistance development. Some coinage metal nanoclusters, such as gold, silver, and copper nanoclusters, can be readily synthesized. These nanoclusters can feature multiple useful properties, including ultra-small size, high catalytic activity, unique photoluminescent properties, and photothermal effect. Coinage metal nanoclusters have been investigated as antimicrobials, but more research is required to tap their full potential. In this review, we discuss multiple advantages and the prospect of using gold/silver/copper nanoclusters as antimicrobials.
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Affiliation(s)
- Dan Li
- Department of Basic Science, Jinzhou Medal University, 40 Songpo Road, Jinzhou 121001, China
| | - Beena Kumari
- Department of Chemistry, Indian Institute of Technology Gandhinagar, India
| | - Jessa Marie Makabenta
- Department of Chemistry, University of Massachusetts Amherst, 710 North Pleasant Street, Amherst, Massachusetts 01003, USA.
| | - Bailong Tao
- College of Bioengineering, Chongqing University, Chongqing 400044, China
| | - Kun Qian
- Department of Basic Science, Jinzhou Medal University, 40 Songpo Road, Jinzhou 121001, China
| | - Xifan Mei
- Department of Basic Science, Jinzhou Medal University, 40 Songpo Road, Jinzhou 121001, China
| | - Vincent M Rotello
- Department of Chemistry, University of Massachusetts Amherst, 710 North Pleasant Street, Amherst, Massachusetts 01003, USA.
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Zorraquín-Peña I, Cueva C, González de Llano D, Bartolomé B, Moreno-Arribas MV. Glutathione-Stabilized Silver Nanoparticles: Antibacterial Activity against Periodontal Bacteria, and Cytotoxicity and Inflammatory Response in Oral Cells. Biomedicines 2020; 8:E375. [PMID: 32977686 PMCID: PMC7598685 DOI: 10.3390/biomedicines8100375] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2020] [Revised: 09/10/2020] [Accepted: 09/22/2020] [Indexed: 12/16/2022] Open
Abstract
Silver nanoparticles (AgNPs) have been proposed as new alternatives to limit bacterial dental plaque because of their antimicrobial activity. Novel glutathione-stabilized silver nanoparticles (GSH-AgNPs) have proven powerful antibacterial properties in food manufacturing processes. Therefore, this study aimed to evaluate the potentiality of GSH-AgNPs for the prevention/treatment of oral infectious diseases. First, the antimicrobial activity of GSH-AgNPs against three oral pathogens (Porphyromonas gingivalis, Fusobacterium nucleatum, and Streptococcus mutans) was evaluated. Results demonstrated the efficiency of GSH-AgNPs in inhibiting the growth of all bacteria, especially S. mutans (IC50 = 23.64 μg/mL, Ag concentration). Second, GSH-AgNPs were assayed for their cytotoxicity (i.e., cell viability) toward a human gingival fibroblast cell line (HGF-1), as an oral epithelial model. Results indicated no toxic effects of GSH-AgNPs at low concentrations (≤6.16 µg/mL, Ag concentration). Higher concentrations resulted in losing cell viability, which followed the Ag accumulation in cells. Finally, the inflammatory response in the HGF-1 cells after their exposure to GSH-AgNPs was measured as the production of immune markers (interleukins 6 and 8 (IL-6 and IL-8) and tumor necrosis factor-alpha (TNF-α)). GSH-AgNPs activates the inflammatory response in human gingival fibroblasts, increasing the production of cytokines. These findings provide new insights for the use of GSH-AgNPs in dental care and encourage further studies for their application.
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Affiliation(s)
| | | | | | | | - M. Victoria Moreno-Arribas
- Institute of Food Science Research (CIAL), CSIC-UAM, C/Nicolás Cabrera, 9, Campus de Cantoblanco, 28049 Madrid, Spain; (I.Z.-P.); (C.C.); (D.G.d.L.); (B.B.)
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15
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AgNP/Alginate Nanocomposite hydrogel for antimicrobial and antibiofilm applications. Carbohydr Polym 2020; 251:117017. [PMID: 33142578 DOI: 10.1016/j.carbpol.2020.117017] [Citation(s) in RCA: 42] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2020] [Revised: 08/23/2020] [Accepted: 08/27/2020] [Indexed: 02/07/2023]
Abstract
The synthesis and specific surface functionalization of antimicrobial silver nanoparticles (AgNPs) and their incorporation into an alginate hydrogel is described. Divalent cation-mediated ionic crosslinking was used to disperse the AgNPs throughout the gel, made possible by -COO- cross-linking sites provided by the surface-enhanced nanoparticles, inspired by the classic egg-box model crosslinking of calcium alginate. An AgNP concentration, 10-20 μg g-1 increased hygrogel elasticity, viscosity, and shear resistance by 45, 30, and 31% respectively. Cryo-TEM revealed evenly distributed AgNP assemblies of discrete AgNPs throughout the gel matrices. FTIR-ATR indicated AgNPs were involved in alginate carboxylate-Ca2+-COO-AgNP crossbridging, which was not achieved through mixing of AgNPs into preformed gels. Live/dead fluorometric assays determined a minimal bactericidal concentration of 25 μg g-1 Ag for 6 microorganisms. Anti-biofilm assays showed species-dependent cell death of 44 -61%, with limited silver ion release of 0.41% and 1.1% after 7 days for Gram positive and negative bacteria, respectively.
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Porter G, Tompkins G, Schwass D, Li K, Waddell J, Meledandri C. Anti-biofilm activity of silver nanoparticle-containing glass ionomer cements. Dent Mater 2020; 36:1096-1107. [DOI: 10.1016/j.dental.2020.05.001] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2020] [Revised: 03/29/2020] [Accepted: 05/05/2020] [Indexed: 12/13/2022]
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Guzmán-Soto I, Omole M, Alarcon EI, McTiernan CD. Lipoic acid capped silver nanoparticles: a facile route to covalent protein capping and oxidative stability within biological systems. RSC Adv 2020; 10:32953-32958. [PMID: 35516471 PMCID: PMC9056624 DOI: 10.1039/d0ra07080g] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2020] [Accepted: 08/27/2020] [Indexed: 12/29/2022] Open
Abstract
Covalent attachment of human serum albumin protein to the surface of spherical lipoic acid capped silver nanoparticles results in the generation of stable nanoparticle–protein hybrids with well defined surface composition. Enhanced stability towards oxidation and in the presence of complex media with high ionic strength, holds promise towards the use of these conjugates as therapeutics in biomedical applications and sensing. Covalent attachment of human serum albumin protein to the surface of spherical lipoic acid capped silver nanoparticles results in the generation of stable nanoparticle–protein hybrids with well defined surface composition.![]()
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Affiliation(s)
- Irene Guzmán-Soto
- Division of Cardiac Surgery
- University of Ottawa Heart Institute
- Ottawa
- Canada
| | - Mary Omole
- Division of Cardiac Surgery
- University of Ottawa Heart Institute
- Ottawa
- Canada
| | - Emilio I. Alarcon
- Division of Cardiac Surgery
- University of Ottawa Heart Institute
- Ottawa
- Canada
- Department of Biochemistry, Microbiology, and Immunology
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