1
|
Madrid RRM, Mathews PD, Pramanik S, Mangiarotti A, Fernandes R, Itri R, Dimova R, Mertins O. Hybrid crystalline bioparticles with nanochannels encapsulating acemannan from Aloe vera: Structure and interaction with lipid membranes. J Colloid Interface Sci 2024; 673:373-385. [PMID: 38878372 DOI: 10.1016/j.jcis.2024.06.073] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2024] [Revised: 06/05/2024] [Accepted: 06/07/2024] [Indexed: 07/26/2024]
Abstract
Smart nanocarrier-based bioactive delivery systems are a current focus in nanomedicine for allowing and boosting diverse disease treatments. In this context, the design of hybrid lipid-polymer particles can provide structure-sensitive features for tailored, triggered, and stimuli-responsive devices. In this work, we introduce hybrid cubosomes that have been surface-modified with a complex of chitosan-N-arginine and alginate, making them pH-responsive. We achieved high-efficiency encapsulation of acemannan, a bioactive polysaccharide from Aloe vera, within the nanochannels of the bioparticle crystalline structure and demonstrated its controlled release under pH conditions mimicking the gastric and intestinal environments. Furthermore, an acemannan-induced phase transition from Im3m cubic symmetry to inverse hexagonal HII phase enhances the bioactive delivery by compressing the lattice spacing of the cubosome water nanochannels, facilitating the expulsion of the encapsulated solution. We also explored the bioparticle interaction with membranes of varying curvatures, revealing thermodynamically driven affinity towards high-curvature lipid membranes and inducing morphological transformations in giant unilamellar vesicles. These findings underscore the potential of these structure-responsive, membrane-active smart bioparticles for applications such as pH-triggered drug delivery platforms for the gastrointestinal tract, and as modulators and promoters of cellular internalization.
Collapse
Affiliation(s)
- Rafael R M Madrid
- Laboratory of Nano Bio Materials (LNBM), Department of Biophysics, Paulista Medical School, Federal University of Sao Paulo, 04023-062 Sao Paulo, Brazil
| | - Patrick D Mathews
- Laboratory of Nano Bio Materials (LNBM), Department of Biophysics, Paulista Medical School, Federal University of Sao Paulo, 04023-062 Sao Paulo, Brazil; Institute of Biosciences, Sao Paulo State University, 18618-689 Botucatu, Brazil
| | - Shreya Pramanik
- Max Planck Institute of Colloids and Interfaces, Science Park Golm, 14476 Potsdam, Germany
| | - Agustín Mangiarotti
- Max Planck Institute of Colloids and Interfaces, Science Park Golm, 14476 Potsdam, Germany
| | - Rodrigo Fernandes
- Applied Physics Department, Institute of Physics, University of Sao Paulo, 05508-900 Sao Paulo, Brazil
| | - Rosangela Itri
- Applied Physics Department, Institute of Physics, University of Sao Paulo, 05508-900 Sao Paulo, Brazil
| | - Rumiana Dimova
- Max Planck Institute of Colloids and Interfaces, Science Park Golm, 14476 Potsdam, Germany.
| | - Omar Mertins
- Laboratory of Nano Bio Materials (LNBM), Department of Biophysics, Paulista Medical School, Federal University of Sao Paulo, 04023-062 Sao Paulo, Brazil.
| |
Collapse
|
2
|
Mathews PD, Gama GS, Megiati HM, Madrid RRM, Garcia BBM, Han SW, Itri R, Mertins O. Flavonoid-Labeled Biopolymer in the Structure of Lipid Membranes to Improve the Applicability of Antioxidant Nanovesicles. Pharmaceutics 2024; 16:141. [PMID: 38276511 PMCID: PMC10819309 DOI: 10.3390/pharmaceutics16010141] [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: 12/19/2023] [Revised: 01/15/2024] [Accepted: 01/17/2024] [Indexed: 01/27/2024] Open
Abstract
Nanovesicles produced with lipids and polymers are promising devices for drug and bioactive delivery and are of great interest in pharmaceutical applications. These nanovesicles can be engineered for improvement in bioavailability, patient compliance or to provide modified release or enhanced delivery. However, their applicability strongly depends on the safety and low immunogenicity of the components. Despite this, the use of unsaturated lipids in nanovesicles, which degrade following oxidation processes during storage and especially during the proper routes of administration in the human body, may yield toxic degradation products. In this study, we used a biopolymer (chitosan) labeled with flavonoid (catechin) as a component over a lipid bilayer for micro- and nanovesicles and characterized the structure of these vesicles in oxidation media. The purpose of this was to evaluate the in situ effect of the antioxidant in three different vesicular systems of medium, low and high membrane curvature. Liposomes and giant vesicles were produced with the phospholipids DOPC and POPC, and crystalline cubic phase with monoolein/DOPC. Concentrations of chitosan-catechin (CHCa) were included in all the vesicles and they were challenged in oxidant media. The cytotoxicity analysis using the MTT assay (3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl-2H-tetrazolium bromide) revealed that concentrations of CHCa below 6.67 µM are non-toxic to HeLa cells. The size and zeta potential of the liposomes evidenced the degradation of their structures, which was minimized by CHCa. Similarly, the membrane of the giant vesicle, which rapidly deteriorated in oxidative solution, was protected in the presence of CHCa. The production of a lipid/CHCa composite cubic phase revealed a specific cubic topology in small-angle X-ray scattering, which was preserved in strong oxidative media. This study demonstrates the specific physicochemical characteristics introduced in the vesicular systems related to the antioxidant CHCa biopolymer, representing a platform for the improvement of composite nanovesicle applicability.
Collapse
Affiliation(s)
- Patrick D. Mathews
- Laboratory of Nano Bio Materials (LNBM), Department of Biophysics, Paulista Medical School, Federal University of Sao Paulo, Sao Paulo 04023-062, Brazil; (P.D.M.); (G.S.G.); (H.M.M.); (R.R.M.M.)
- Institute of Biosciences, Sao Paulo State University, Botucatu 18618-689, Brazil
| | - Gabriella S. Gama
- Laboratory of Nano Bio Materials (LNBM), Department of Biophysics, Paulista Medical School, Federal University of Sao Paulo, Sao Paulo 04023-062, Brazil; (P.D.M.); (G.S.G.); (H.M.M.); (R.R.M.M.)
| | - Hector M. Megiati
- Laboratory of Nano Bio Materials (LNBM), Department of Biophysics, Paulista Medical School, Federal University of Sao Paulo, Sao Paulo 04023-062, Brazil; (P.D.M.); (G.S.G.); (H.M.M.); (R.R.M.M.)
| | - Rafael R. M. Madrid
- Laboratory of Nano Bio Materials (LNBM), Department of Biophysics, Paulista Medical School, Federal University of Sao Paulo, Sao Paulo 04023-062, Brazil; (P.D.M.); (G.S.G.); (H.M.M.); (R.R.M.M.)
| | - Bianca B. M. Garcia
- Interdisciplinary Center for Gene Therapy, Paulista Medical School, Federal University of Sao Paulo, Sao Paulo 04023-062, Brazil; (B.B.M.G.); (S.W.H.)
| | - Sang W. Han
- Interdisciplinary Center for Gene Therapy, Paulista Medical School, Federal University of Sao Paulo, Sao Paulo 04023-062, Brazil; (B.B.M.G.); (S.W.H.)
| | - Rosangela Itri
- Applied Physics Department, Institute of Physics, University of Sao Paulo, Sao Paulo 05508-900, Brazil;
| | - Omar Mertins
- Laboratory of Nano Bio Materials (LNBM), Department of Biophysics, Paulista Medical School, Federal University of Sao Paulo, Sao Paulo 04023-062, Brazil; (P.D.M.); (G.S.G.); (H.M.M.); (R.R.M.M.)
| |
Collapse
|
3
|
Mathews PD, Mertins O, Angelov B, Angelova A. Cubosomal lipid nanoassemblies with pH-sensitive shells created by biopolymer complexes: A synchrotron SAXS study. J Colloid Interface Sci 2021; 607:440-450. [PMID: 34509118 DOI: 10.1016/j.jcis.2021.08.187] [Citation(s) in RCA: 28] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2021] [Revised: 08/19/2021] [Accepted: 08/28/2021] [Indexed: 12/19/2022]
Abstract
We report a strategy for sustainable development of pH-responsive cubic liquid crystalline nanoparticles (cubosomes), in which the structure-defining lyotropic nonlamellar lipid and the eventually encapsulated guest molecules can be protected by pH-sensitive polyelectrolyte shells with mucoadhesive properties. Bulk non-lamellar phases as well as pH-responsive polyelectrolyte-modified nanocarriers were formed by spontaneous assembly of the nonlamellar lipid monoolein and two biopolymers tailored in nanocomplexes with pH-dependent net charge. The mesophase particles involved positively charged N-arginine-modified chitosan (CHarg) and negatively charged alginate (ALG) chains assembled at different biopolymer concentrations and charge ratios into a series of pH-responsive complexes. The roles of Pluronic F127 as a dispersing agent and a stabilizer of the nanoscale dispersions were examined. Synchrotron small-angle X-ray scattering (SAXS) investigations were performed at several N-arginine-modified chitosan/alginate ratios (CHarg/ALG with 10, 15 and 20 wt% ALG relative to CHarg) and varying pH values mimicking the pH conditions of the gastrointestinal route. The structural parameters characterizing the inner cubic liquid crystalline organizations of the nanocarriers were determined as well as the particle sizes and stability on storage. The surface charge variations, influencing the measured zeta-potentials, evidenced the inclusion of the CHarg/ALG biopolymer complexes into the lipid nanoassemblies. The polyelectrolyte shells rendered the hybrid cubosome nanocarriers pH-sensitive and influenced the swelling of their lipid-phase core as revealed by the acquired SAXS patterns. The pH-responsiveness and the mucoadhesive features of the cubosomal lipid/polyelectrolyte nanocomplexes may be of interest for in vivo drug delivery applications.
Collapse
Affiliation(s)
- Patrick D Mathews
- Laboratory of Nano Bio Materials (LNBM), Department of Biophysics, Paulista Medical School, Federal University of Sao Paulo (UNIFESP), 04023-062 Sao Paulo, Brazil
| | - Omar Mertins
- Laboratory of Nano Bio Materials (LNBM), Department of Biophysics, Paulista Medical School, Federal University of Sao Paulo (UNIFESP), 04023-062 Sao Paulo, Brazil; Institut Galien Paris-Saclay UMR8612, Université Paris-Saclay, CNRS, F-92296 Châtenay-Malabry, France.
| | - Borislav Angelov
- Institute of Physics, ELI Beamlines, Academy of Sciences of the Czech Republic, CZ-18221 Prague, Czech Republic
| | - Angelina Angelova
- Institut Galien Paris-Saclay UMR8612, Université Paris-Saclay, CNRS, F-92296 Châtenay-Malabry, France.
| |
Collapse
|
4
|
Mertins O, Mathews PD, Angelova A. Advances in the Design of pH-Sensitive Cubosome Liquid Crystalline Nanocarriers for Drug Delivery Applications. NANOMATERIALS (BASEL, SWITZERLAND) 2020; 10:E963. [PMID: 32443582 PMCID: PMC7281514 DOI: 10.3390/nano10050963] [Citation(s) in RCA: 58] [Impact Index Per Article: 14.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/29/2020] [Revised: 04/29/2020] [Accepted: 05/03/2020] [Indexed: 01/10/2023]
Abstract
Nanostructure bicontinuous cubic phase self-assembled materials are receiving expanding applications as biocompatible delivery systems in various therapeutic fields. The functionalization of cubosome, spongosome, hexosome and liposome nanocarriers by pH-sensitive lipids and/or pH-sensitive polymer shells offers new opportunities for oral and topical drug delivery towards a new generation of cancer therapies. The electrochemical behavior of drug compounds may favor pH-triggered drug release as well. Here, we highlight recent investigations, which explore the phase behavior of mixed nonlamellar lipid/fatty acid or phospholipid systems for the design of pH-responsive and mucoadhesive drug delivery systems with sustained-release properties. X-ray diffraction and small-angle X-ray scattering (SAXS) techniques are widely used in the development of innovative delivery assemblies through detailed structural analyses of multiple amphiphilic compositions from the lipid/co-lipid/water phase diagrams. pH-responsive nanoscale materials and nanoparticles are required for challenging therapeutic applications such as oral delivery of therapeutic proteins and peptides as well as of poorly water-soluble substances. Perspective nanomedicine developments with smart cubosome nanocarriers may exploit compositions elaborated to overcome the intestinal obstacles, dual-drug loaded pH-sensitive liquid crystalline architectures aiming at enhanced therapeutic efficacy, as well as composite (lipid/polyelectrolyte) types of mucoadhesive controlled release colloidal cubosomal formulations for the improvement of the drugs' bioavailability.
Collapse
Affiliation(s)
- Omar Mertins
- Institut Galien Paris-Saclay UMR8612, Université Paris-Saclay, CNRS, F-92296 Châtenay-Malabry, France;
- Laboratory of Nano Bio Materials (LNBM), Department of Biophysics, Paulista Medical School, Federal University of Sao Paulo (UNIFESP), Sao Paulo 04023-062, Brazil;
| | - Patrick D. Mathews
- Laboratory of Nano Bio Materials (LNBM), Department of Biophysics, Paulista Medical School, Federal University of Sao Paulo (UNIFESP), Sao Paulo 04023-062, Brazil;
- Muséum National d’Histoire Naturelle, Sorbonne Université, CP 26, 75231 Paris, France
| | - Angelina Angelova
- Institut Galien Paris-Saclay UMR8612, Université Paris-Saclay, CNRS, F-92296 Châtenay-Malabry, France;
| |
Collapse
|
5
|
Neužilová B, Ondrák L, Čuba V, Múčka V. ETHANOL AS A MODIFIER OF RADIATION SENSITIVITY OF LIVING CELLS AGAINST UV-C RADIATION. RADIATION PROTECTION DOSIMETRY 2019; 186:191-195. [PMID: 31808535 DOI: 10.1093/rpd/ncz200] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/16/2019] [Accepted: 08/14/2019] [Indexed: 06/10/2023]
Abstract
The protection of Escherichia coli bacteria and the yeast Saccharomyces cerevisiae against UV-C radiation by ethanol was studied. It was found that the fraction of surviving cells increases with increasing ethanol concentration. The specific protection depends on the dose rate, concentration range of ethanol, and it is higher for yeast compared to the bacteria.
Collapse
Affiliation(s)
- Barbora Neužilová
- Faculty of Nuclear Sciences and Physical Engineering, Czech Technical University in Prague, Břehová 1, 110 00 Prague, Czech Republic
| | - Lukáš Ondrák
- Faculty of Nuclear Sciences and Physical Engineering, Czech Technical University in Prague, Břehová 1, 110 00 Prague, Czech Republic
- Center of Nuclear Medicine, 190 00 Prague, Czech Republic
| | - Václav Čuba
- Faculty of Nuclear Sciences and Physical Engineering, Czech Technical University in Prague, Břehová 1, 110 00 Prague, Czech Republic
| | - Viliam Múčka
- Faculty of Nuclear Sciences and Physical Engineering, Czech Technical University in Prague, Břehová 1, 110 00 Prague, Czech Republic
| |
Collapse
|
6
|
Trapani A, Mandracchia D, Tripodo G, Cometa S, Cellamare S, De Giglio E, Klepetsanis P, Antimisiaris SG. Protection of dopamine towards autoxidation reaction by encapsulation into non-coated- or chitosan- or thiolated chitosan-coated-liposomes. Colloids Surf B Biointerfaces 2018; 170:11-19. [PMID: 29859476 DOI: 10.1016/j.colsurfb.2018.05.049] [Citation(s) in RCA: 26] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2017] [Revised: 04/13/2018] [Accepted: 05/22/2018] [Indexed: 01/06/2023]
Abstract
The aim of this work is to evaluate the potential of non-coated-, chitosan-(CS)- or chitosan-glutathione conjugate- (CS-GSH)-coated liposomes to protect the neurotransmitter Dopamine (DA) from the autoxidation reaction in neutral/alkaline conditions. This may be of interest in the development of nanotechnology-based approaches to improve Parkinson's disease treatment because decreased ROS production and reduced DA associated neurotoxicity are expected. For the mentioned purposes, DA-loaded vesicles were prepared by the Dried Reconstituted Vesicles (DRV) method, and were subsequently coated using solutions of polycations. As for the mean diameters of liposomes so prepared, the CS-GSH coated liposomes showed a significant decrease in size compared to the corresponding non-coated and CS-coated vesicles. The surface charge of DA-loaded non-coated liposomes was -10.8 mV, whereas the CS or CS-GSH coated vesicles showed a slightly positive ζ-potential. The capability of the herein studied vesicles to prevent DA autoxidation was evaluated by visual inspection, monitoring DA/lipid ratio as such and under stressed conditions. The results suggest that liposome formulations partially protect the neurotransmitter from the autoxidation reaction. In particular, the CS-GSH coated liposomes were more stable than the corresponding CS-coated and non-coated ones against the oxidative damage and were found to deliver the neurotransmitter in a sustained manner. Probably, this is due to the localization of the neurotransmitter in the core of the vesicles as indicated by XPS which confirmed the absence of the neurotransmitter on the surface of these vesicles.
Collapse
Affiliation(s)
- A Trapani
- Department of Pharmacy-Drug Sciences, University of Bari "Aldo Moro", Via Orabona, 4, 70125, Bari, Italy.
| | - D Mandracchia
- Department of Pharmacy-Drug Sciences, University of Bari "Aldo Moro", Via Orabona, 4, 70125, Bari, Italy
| | - G Tripodo
- Department of Drug Sciences, University of Pavia, Viale Taramelli, 12, 27100, Pavia, Italy
| | - S Cometa
- Jaber Innovation s.r.l., Via Calcutta 8, Rome, 00144, Italy
| | - S Cellamare
- Department of Pharmacy-Drug Sciences, University of Bari "Aldo Moro", Via Orabona, 4, 70125, Bari, Italy
| | - E De Giglio
- Department of Chemistry, University of Bari "Aldo Moro", Via Orabona, 4, 70125, Bari, Italy
| | - P Klepetsanis
- Dept. of Pharmacy, University of Patras, and FORTH/ICE-HT, Rio, 26504, Greece; Institute of Chemical Engineering Foundation for Research and Technology Hellas, FORTH/ICE-HT, 26504, Platani, Patras, Greece.
| | - S G Antimisiaris
- Dept. of Pharmacy, University of Patras, and FORTH/ICE-HT, Rio, 26504, Greece; Institute of Chemical Engineering Foundation for Research and Technology Hellas, FORTH/ICE-HT, 26504, Platani, Patras, Greece
| |
Collapse
|
7
|
Mertins O, Lobo SE, Mathews PD, Han SW. Interaction of pDNA with reverse phase chitosome. Colloids Surf A Physicochem Eng Asp 2018. [DOI: 10.1016/j.colsurfa.2018.02.005] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023]
|
8
|
Mathews PD, Fernandes Patta ACM, Gonçalves JV, Gama GDS, Garcia ITS, Mertins O. Targeted Drug Delivery and Treatment of Endoparasites with Biocompatible Particles of pH-Responsive Structure. Biomacromolecules 2018; 19:499-510. [PMID: 29283560 DOI: 10.1021/acs.biomac.7b01630] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Biomaterials conceived for vectorization of bioactives are currently considered for biomedical, biological, and environmental applications. We have produced a pH-sensitive biomaterial composed of natural source alginate and chitosan polysaccharides for application as a drug delivery system via oral administration. The composite particle preparation was in situ monitored by means of isothermal titration calorimetry. The strong interaction established between the macromolecules during particle assembly led to 0.60 alginate/chitosan effective binding sites with an intense exothermic effect and negative enthalpy variation on the order of a thousand kcal/mol. In the presence of model drugs mebendazole and ivermectin, with relatively small and large structures, respectively, mebendazole reduced the amount of chitosan monomers available to interact with alginate by 27%, which was not observed for ivermectin. Nevertheless, a state of intense negative Gibbs energy and large entropic decrease was achieved, providing evidence that formation of particles is thermodynamically driven and favored. Small-angle X-ray scattering provided further evidence of similar surface aspects independent of the presence of drug. The physical responses of the particles to pH variation comprise partial hydration, swelling, and the predominance of positive surface charge in strong acid medium, whereas ionization followed by deprotonation leads to compaction and charge reversal rather than new swelling in mild and slightly acidic mediums, respectively. In vivo performance was evaluated in the treatment of endoparasites in Corydoras fish. Systematically with a daily base oral administration, particles significantly reduced the infections over 15 days of treatment. The experiments provide evidence that utilizing particles granted and boosted the action of the antiparasitic drugs, leading to substantial reduction or elimination of infection. Hence, the pH-responsive particles represent a biomaterial with prominent characteristics that is promising for the development of targeted oral drug delivery.
Collapse
Affiliation(s)
- Patrick D Mathews
- Department of Biophysics, Paulista School of Medicine, Federal University of Sao Paulo , Sao Paulo 04023-062, Brazil
| | - Ana C M Fernandes Patta
- Department of Biophysics, Paulista School of Medicine, Federal University of Sao Paulo , Sao Paulo 04023-062, Brazil
| | - Joao V Gonçalves
- Department of Biophysics, Paulista School of Medicine, Federal University of Sao Paulo , Sao Paulo 04023-062, Brazil
| | - Gabriella Dos Santos Gama
- Department of Biophysics, Paulista School of Medicine, Federal University of Sao Paulo , Sao Paulo 04023-062, Brazil
| | - Irene Teresinha Santos Garcia
- Department of Physical-Chemistry, Institute of Chemistry, Federal University of Rio Grande do Sul , Porto Alegre 91501-970, Brazil
| | - Omar Mertins
- Department of Biophysics, Paulista School of Medicine, Federal University of Sao Paulo , Sao Paulo 04023-062, Brazil
| |
Collapse
|
9
|
Rheological properties of gallic acid-grafted-chitosans with different substitution degrees. Lebensm Wiss Technol 2016. [DOI: 10.1016/j.lwt.2016.08.018] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
|
10
|
Mathews PD, Mertins O. Dispersion of chitosan in liquid crystalline lamellar phase: Production of biofriendly hydrogel of nano cubic topology. Carbohydr Polym 2016; 157:850-857. [PMID: 27987999 DOI: 10.1016/j.carbpol.2016.10.071] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2016] [Revised: 09/28/2016] [Accepted: 10/23/2016] [Indexed: 02/04/2023]
Abstract
Bicontinuous cubic phases were produced with introduction of chitosan in phospholipid/water hydrogel, providing composites of defined molecular organization. The ratio of lipid/water was constant and swelling of lipids bilayer is delimited by incorporation of polymer molecules into the structure. By means of synchrotron small angle X-ray scattering we identified topologies of coexisting cubic phases. The expected liquid crystalline Lα lamellar phase was suppressed by 0.2wt% chitosan leading to formation of diamond Pn3m and gyroid Ia3d cubic topology, with close lattice distances. An increment to 0.4wt% chitosan caused large increase in Pn3m lattice distance. However a higher 0.6wt% evolved this phase to a newly acquired primitive Im3m topology. The structuring process of the three-dimensional complex network is principally governed by demands of chitosan physical requirements over lipids bilayers interfacial curvature. The composite hydrogel of specific topologies presents reduced time release of gallic acid and may find application as new material for time-sustained delivery of bioactive compounds.
Collapse
Affiliation(s)
- Patrick D Mathews
- Department of Animal Biology, Institute of Biology, State University of Campinas, 13083-970 Campinas, Brazil.
| | - Omar Mertins
- Department of Biophysics, Paulista School of Medicine, Federal University of Sao Paulo, 04023-062 Sao Paulo, Brazil.
| |
Collapse
|