1
|
Li P, Malveau C, Zhu XX, Wuest JD. Using Nuclear Magnetic Resonance Spectroscopy to Probe Hydrogels Formed by Sodium Deoxycholate. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2022; 38:5111-5118. [PMID: 34730971 DOI: 10.1021/acs.langmuir.1c02175] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/13/2023]
Abstract
Hydrogels of bile acids and their salts are promising materials for drug delivery, cellular immobilization, and other applications. However, these hydrogels are poorly understood at the molecular level, and further study is needed to allow improved materials to be created by design. We have used NMR spectroscopy to probe hydrogels formed from mixtures of formic acid and sodium deoxycholate (NaDC), a common bile acid salt. By assaying the ratio of deoxycholate molecules that are immobilized as part of the fibrillar network of the hydrogels and those that can diffuse, we have found that 65% remain free under typical conditions. The network appears to be composed of both the acid and salt forms of deoxycholate, possibly because a degree of charge inhibits excessive aggregation and precipitation of the fibrils. Spin-spin relaxation times provided a molecular-level estimate of the temperature of gel-sol transition (42 °C), which is virtually the same as the value determined by analyzing macroscopic parameters. Saturation transfer difference (STD) NMR spectroscopy established that formic acid, which is present mainly as formate, is not immobilized as part of the gelating network. In contrast, HDO interacts with the network, which presumably has a surface with exposed hydrophilic groups that form hydrogen bonds with water. Moreover, the STD NMR experiments revealed that the network is a dynamic entity, with molecules of deoxycholate associating and dissociating reversibly. This exchange appears to occur preferentially by contact of the hydrophobic edges or faces of free molecules of deoxycholate with those of molecules immobilized as components of the network. In addition, DOSY experiments revealed that gelation has little effect on the diffusion of free NaDC and HDO.
Collapse
Affiliation(s)
- Puzhen Li
- Département de Chimie, Université de Montréal, Montréal, Québec H2V 0B3 Canada
| | - Cédric Malveau
- Département de Chimie, Université de Montréal, Montréal, Québec H2V 0B3 Canada
| | - X X Zhu
- Département de Chimie, Université de Montréal, Montréal, Québec H2V 0B3 Canada
| | - James D Wuest
- Département de Chimie, Université de Montréal, Montréal, Québec H2V 0B3 Canada
| |
Collapse
|
2
|
Martí-Centelles R, Dolz-Pérez I, De la O J, Ontoria-Oviedo I, Sepúlveda P, Nebot VJ, Vicent MJ, Escuder B. Two-Component Peptidic Molecular Gels for Topical Drug Delivery of Naproxen. ACS APPLIED BIO MATERIALS 2021. [DOI: 10.1021/acsabm.0c01422] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Affiliation(s)
- Rosa Martí-Centelles
- Departament de Química Inorgànica i Orgànica, Universitat Jaume I, Castelló 12071, Spain
| | - Irene Dolz-Pérez
- Polymer Therapeutics Laboratory, Centro de Investigación Príncipe Felipe, Valencia 46012, Spain
| | - Jaciel De la O
- Polypeptide Therapeutic Solutions S.L., 46980 Paterna, Spain
| | - Imelda Ontoria-Oviedo
- Regenerative Medicine and Heart Transplantation Unit, Instituto de Investigación Sanitaria La Fe, Valencia 46026, Spain
| | - Pilar Sepúlveda
- Regenerative Medicine and Heart Transplantation Unit, Instituto de Investigación Sanitaria La Fe, Valencia 46026, Spain
| | - Vicent J. Nebot
- Polypeptide Therapeutic Solutions S.L., 46980 Paterna, Spain
| | - Maria J. Vicent
- Polymer Therapeutics Laboratory, Centro de Investigación Príncipe Felipe, Valencia 46012, Spain
| | - Beatriu Escuder
- Departament de Química Inorgànica i Orgànica, Universitat Jaume I, Castelló 12071, Spain
| |
Collapse
|
3
|
Calabrese V, Muñoz-García JC, Schmitt J, da Silva MA, Scott JL, Angulo J, Khimyak YZ, Edler KJ. Understanding heat driven gelation of anionic cellulose nanofibrils: Combining saturation transfer difference (STD) NMR, small angle X-ray scattering (SAXS) and rheology. J Colloid Interface Sci 2018; 535:205-213. [PMID: 30293046 DOI: 10.1016/j.jcis.2018.09.085] [Citation(s) in RCA: 27] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2018] [Revised: 09/21/2018] [Accepted: 09/24/2018] [Indexed: 11/18/2022]
Abstract
A novel mechanism of heat-triggered gelation for oxidised cellulose nanofibrils (OCNF) is reported. We demonstrate that a synergistic approach combining rheology, small-angle X-ray scattering (SAXS) and saturation transfer difference NMR (STD NMR) experiments enables a detailed characterisation of gelation at different length scales. OCNF dispersions experience an increase in solid-like behaviour upon heating as evidenced by rheological studies, associated with enhanced interfibrillar interactions measured using SAXS. Interactions result in an increased fibrillar overlap and increased population of confined water molecules monitored by STD NMR. In comparison, cationic cellulose nanofibrils (produced by reaction of cellulose with trimethylglycidylammonium chloride) were found to be heat-unresponsive.
Collapse
Affiliation(s)
- Vincenzo Calabrese
- Department of Chemistry, University of Bath, Claverton Down, Bath BA2 7AY, UK
| | - Juan C Muñoz-García
- School of Pharmacy, University of East Anglia, Norwich Research Park, Norwich NR4 7TJ, UK
| | - Julien Schmitt
- Department of Chemistry, University of Bath, Claverton Down, Bath BA2 7AY, UK
| | - Marcelo A da Silva
- Department of Chemistry, University of Bath, Claverton Down, Bath BA2 7AY, UK
| | - Janet L Scott
- Department of Chemistry, University of Bath, Claverton Down, Bath BA2 7AY, UK; Centre for Sustainable Chemical Technology, University of Bath, Claverton Down, Bath BA2 7AY, UK.
| | - Jesús Angulo
- School of Pharmacy, University of East Anglia, Norwich Research Park, Norwich NR4 7TJ, UK.
| | - Yaroslav Z Khimyak
- School of Pharmacy, University of East Anglia, Norwich Research Park, Norwich NR4 7TJ, UK.
| | - Karen J Edler
- Department of Chemistry, University of Bath, Claverton Down, Bath BA2 7AY, UK.
| |
Collapse
|
4
|
Angelerou MF, Frederix PWJM, Wallace M, Yang B, Rodger A, Adams DJ, Marlow M, Zelzer M. Supramolecular Nucleoside-Based Gel: Molecular Dynamics Simulation and Characterization of Its Nanoarchitecture and Self-Assembly Mechanism. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2018; 34:6912-6921. [PMID: 29757652 PMCID: PMC6078381 DOI: 10.1021/acs.langmuir.8b00646] [Citation(s) in RCA: 26] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/26/2018] [Revised: 05/09/2018] [Indexed: 05/27/2023]
Abstract
Among the diversity of existing supramolecular hydrogels, nucleic acid-based hydrogels are of particular interest for potential drug delivery and tissue engineering applications because of their inherent biocompatibility. Hydrogel performance is directly related to the nanostructure and the self-assembly mechanism of the material, an aspect that is not well-understood for nucleic acid-based hydrogels in general and has not yet been explored for cytosine-based hydrogels in particular. Herein, we use a broad range of experimental characterization techniques along with molecular dynamics (MD) simulation to demonstrate the complementarity and applicability of both approaches for nucleic acid-based gelators in general and propose the self-assembly mechanism for a novel supramolecular gelator, N4-octanoyl-2'-deoxycytidine. The experimental data and the MD simulation are in complete agreement with each other and demonstrate the formation of a hydrophobic core within the fibrillar structures of these mainly water-containing materials. The characterization of the distinct duality of environments in this cytidine-based gel will form the basis for further encapsulation of both small hydrophobic drugs and biopharmaceuticals (proteins and nucleic acids) for drug delivery and tissue engineering applications.
Collapse
Affiliation(s)
| | - Pim W. J. M. Frederix
- Faculty
of Science and Engineering, University of
Groningen, Groningen 9747 AG, The Netherlands
| | - Matthew Wallace
- School
of Pharmacy, University of East Anglia, Norwich NR4 7TJ, U.K.
| | - Bin Yang
- School
of Pharmacy, University of Nottingham, Nottingham NG7 2RD, U.K.
| | - Alison Rodger
- Department
of Molecular Sciences, Macquarie University, Sydney, New South Wales 2109, Australia
| | - Dave J. Adams
- School
of Chemistry, University of Glasgow, Glasgow G12 8QQ, U.K.
| | - Maria Marlow
- School
of Pharmacy, University of Nottingham, Nottingham NG7 2RD, U.K.
| | - Mischa Zelzer
- School
of Pharmacy, University of Nottingham, Nottingham NG7 2RD, U.K.
| |
Collapse
|
5
|
Ramalhete SM, Nartowski KP, Sarathchandra N, Foster JS, Round AN, Angulo J, Lloyd GO, Khimyak YZ. Supramolecular Amino Acid Based Hydrogels: Probing the Contribution of Additive Molecules using NMR Spectroscopy. Chemistry 2017; 23:8014-8024. [PMID: 28401991 PMCID: PMC5575562 DOI: 10.1002/chem.201700793] [Citation(s) in RCA: 38] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2017] [Indexed: 11/08/2022]
Abstract
Supramolecular hydrogels are composed of self-assembled solid networks that restrict the flow of water. l-Phenylalanine is the smallest molecule reported to date to form gel networks in water, and it is of particular interest due to its crystalline gel state. Single and multi-component hydrogels of l-phenylalanine are used herein as model materials to develop an NMR-based analytical approach to gain insight into the mechanisms of supramolecular gelation. Structure and composition of the gel fibres were probed using PXRD, solid-state NMR experiments and microscopic techniques. Solution-state NMR studies probed the properties of free gelator molecules in an equilibrium with bound molecules. The dynamics of exchange at the gel/solution interfaces was investigated further using high-resolution magic angle spinning (HR-MAS) and saturation transfer difference (STD) NMR experiments. This approach allowed the identification of which additive molecules contributed in modifying the material properties.
Collapse
Affiliation(s)
| | - Karol P. Nartowski
- School of PharmacyUniversity of East AngliaNorwich Research ParkNR4 7TJUK
- Current address: Department of Drug Form TechnologyFaculty of PharmacyWroclaw Medical Universityul. Borowska 21150-556WroclawPoland
| | | | - Jamie S. Foster
- Institute of Chemical Sciences, School of Engineering and Physical SciencesHeriot-Watt UniversityEH14 4ASUK
| | - Andrew N. Round
- School of PharmacyUniversity of East AngliaNorwich Research ParkNR4 7TJUK
| | - Jesús Angulo
- School of PharmacyUniversity of East AngliaNorwich Research ParkNR4 7TJUK
| | - Gareth O. Lloyd
- Institute of Chemical Sciences, School of Engineering and Physical SciencesHeriot-Watt UniversityEH14 4ASUK
| | | |
Collapse
|
6
|
Wallace M, Iggo JA, Adams DJ. Probing the surface chemistry of self-assembled peptide hydrogels using solution-state NMR spectroscopy. SOFT MATTER 2017; 13:1716-1727. [PMID: 28165092 DOI: 10.1039/c6sm02404a] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/21/2023]
Abstract
The surface chemistry of self-assembled hydrogel fibres - their charge, hydrophobicity and ion-binding dynamics - is recognised to play an important role in determining how the gels develop as well as their suitability for different applications. However, to date there are no established methodologies for the study of this surface chemistry. Here, we demonstrate how solution-state NMR spectroscopy can be employed to measure the surface chemical properties of the fibres in a range of hydrogels formed from N-functionalised dipeptides, an effective and versatile class of gelator that has attracted much attention. By studying the interactions with the gel fibres of a diverse range of probe molecules and ions, we can simultaneously study a number of surface chemical properties of the NMR invisible fibres in an essentially non-invasive manner. Our results yield fresh insights into the materials. Most notably, gel fibres assembled using different tiggering methods bear differing amounts of negative charge as a result of a partial deprotonation of the carboxylic acid groups of the gelators. We also demonstrate how chemical shift imaging (CSI) techniques can be applied to follow the formation of hydrogels along chemical gradients. We apply CSI to study the binding of Ca2+ and subsequent gelation of peptide assemblies at alkaline pH. Using metal ion-binding molecules as probes, we are able to detect the presence of bound Ca2+ ions on the surface of the gel fibres. We briefly explore how knowledge of the surface chemical properties of hydrogels could be used to inform their practical application in fields such as drug delivery and environmental remediation.
Collapse
Affiliation(s)
- Matthew Wallace
- Department of Chemistry, University of Liverpool, Liverpool, L69 7ZD, UK.
| | - Jonathan A Iggo
- Department of Chemistry, University of Liverpool, Liverpool, L69 7ZD, UK.
| | - Dave J Adams
- Department of Chemistry, University of Liverpool, Liverpool, L69 7ZD, UK.
| |
Collapse
|
7
|
Barouti G, Liow SS, Dou Q, Ye H, Orione C, Guillaume SM, Loh XJ. New Linear and Star-Shaped Thermogelling Poly([R]-3-hydroxybutyrate) Copolymers. Chemistry 2016; 22:10501-12. [PMID: 27345491 DOI: 10.1002/chem.201601404] [Citation(s) in RCA: 73] [Impact Index Per Article: 9.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2016] [Indexed: 12/20/2022]
Abstract
The synthesis of multi-arm poly([R]-3-hydroxybutyrate) (PHB)-based triblock copolymers (poly([R]-3-hydroxybutyrate)-b-poly(N-isopropylacrylamide)-b-[[poly(methyl ether methacrylate)-g-poly(ethylene glycol)]-co-[poly(methacrylate)-g-poly(propylene glycol)]], PHB-b-PNIPAAM-b-(PPEGMEMA-co-PPPGMA), and their subsequent self-assembly into thermo-responsive hydrogels is described. Atom transfer radical polymerization (ATRP) of N-isopropylacrylamide (NIPAAM) followed by poly(ethylene glycol) methyl ether methacrylate (PEGMEMA) and poly(propylene glycol) methacrylate (PPGMA) was achieved from bromoesterified multi-arm PHB macroinitiators. The composition of the resulting copolymers was investigated by (1) H and (13) C J-MOD NMR spectroscopy as well as size-exclusion chromatography (SEC), thermogravimetric analysis (TGA), and differential scanning calorimetry (DSC). The copolymers featuring different architectures and distinct hydrophilic/hydrophobic contents were found to self-assemble into thermo-responsive gels in aqueous solution. Rheological studies indicated that the linear one-arm PHB-based copolymer tend to form a micellar solution, whereas the two- and four-arm PHB-based copolymers afforded gels with enhanced mechanical properties and solid-like behavior. These investigations are the first to correlate the gelation properties to the arm number of a PHB-based copolymer. All copolymers revealed a double thermo-responsive behavior due to the NIPAAM and PPGMA blocks, thus allowing first the copolymer self-assembly at room temperature, and then the delivery of a drug at body temperature (37 °C). The non-significant toxic response of the gels, as assessed by the cell viability of the CCD-112CoN human fibroblast cell line with different concentrations of the triblock copolymers ranging from 0.03 to 1 mg mL(-1) , suggest that these PHB-based thermo-responsive gels are promising candidate biomaterials for drug-delivery applications.
Collapse
Affiliation(s)
- Ghislaine Barouti
- Institut des Sciences Chimiques de Rennes, UMR 6226 CNRS, Université de Rennes 1, Campus de Beaulieu, 263 Avenue du Général Leclerc, 35042, Rennes Cedex, France
- Institute of Materials Research and Engineering (IMRE), 3 Research Link, Singapore, 117602, Singapore
| | - Sing Shy Liow
- Institute of Materials Research and Engineering (IMRE), 3 Research Link, Singapore, 117602, Singapore
| | - Qingqing Dou
- Institute of Materials Research and Engineering (IMRE), 3 Research Link, Singapore, 117602, Singapore
| | - Hongye Ye
- Institute of Materials Research and Engineering (IMRE), 3 Research Link, Singapore, 117602, Singapore
| | - Clément Orione
- Centre Régional de Mesures Physiques de l'Ouest, Université de Rennes 1, Campus de Beaulieu, 263 Avenue du Général Leclerc, 35042, Rennes Cedex, France
| | - Sophie M Guillaume
- Institut des Sciences Chimiques de Rennes, UMR 6226 CNRS, Université de Rennes 1, Campus de Beaulieu, 263 Avenue du Général Leclerc, 35042, Rennes Cedex, France.
| | - Xian Jun Loh
- Institute of Materials Research and Engineering (IMRE), 3 Research Link, Singapore, 117602, Singapore.
- Department of Materials Science and Engineering, National University of Singapore, 9 Engineering Drive 1, Singapore, 117576, Singapore.
- Singapore Eye Research Institute, 11 Third Hospital Avenue, Singapore, 168751, Singapore.
| |
Collapse
|