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Harun-Or-Rashid M, Aktar MN, Hossain MS, Sarkar N, Islam MR, Arafat ME, Bhowmik S, Yusa SI. Recent Advances in Micro- and Nano-Drug Delivery Systems Based on Natural and Synthetic Biomaterials. Polymers (Basel) 2023; 15:4563. [PMID: 38231996 PMCID: PMC10708661 DOI: 10.3390/polym15234563] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2023] [Revised: 11/22/2023] [Accepted: 11/26/2023] [Indexed: 01/19/2024] Open
Abstract
Polymeric drug delivery technology, which allows for medicinal ingredients to enter a cell more easily, has advanced considerably in recent decades. Innovative medication delivery strategies use biodegradable and bio-reducible polymers, and progress in the field has been accelerated by future possible research applications. Natural polymers utilized in polymeric drug delivery systems include arginine, chitosan, dextrin, polysaccharides, poly(glycolic acid), poly(lactic acid), and hyaluronic acid. Additionally, poly(2-hydroxyethyl methacrylate), poly(N-isopropyl acrylamide), poly(ethylenimine), dendritic polymers, biodegradable polymers, and bioabsorbable polymers as well as biomimetic and bio-related polymeric systems and drug-free macromolecular therapies have been employed in polymeric drug delivery. Different synthetic and natural biomaterials are in the clinical phase to mitigate different diseases. Drug delivery methods using natural and synthetic polymers are becoming increasingly common in the pharmaceutical industry, with biocompatible and bio-related copolymers and dendrimers having helped cure cancer as drug delivery systems. This review discusses all the above components and how, by combining synthetic and biological approaches, micro- and nano-drug delivery systems can result in revolutionary polymeric drug and gene delivery devices.
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Affiliation(s)
- Md. Harun-Or-Rashid
- Department of Applied Chemistry, Graduate School of Engineering, University of Hyogo, 2167 Shosha, Himeji 671-2280, Hyogo, Japan; (M.H.-O.-R.); (M.N.A.); (S.B.)
| | - Most. Nazmin Aktar
- Department of Applied Chemistry, Graduate School of Engineering, University of Hyogo, 2167 Shosha, Himeji 671-2280, Hyogo, Japan; (M.H.-O.-R.); (M.N.A.); (S.B.)
| | - Md. Sabbir Hossain
- Department of Pharmacy, Faculty of Allied Health Sciences, Daffodil International University, Dhaka 1207, Bangladesh; (M.S.H.); (N.S.); (M.R.I.); (M.E.A.)
| | - Nadia Sarkar
- Department of Pharmacy, Faculty of Allied Health Sciences, Daffodil International University, Dhaka 1207, Bangladesh; (M.S.H.); (N.S.); (M.R.I.); (M.E.A.)
| | - Md. Rezaul Islam
- Department of Pharmacy, Faculty of Allied Health Sciences, Daffodil International University, Dhaka 1207, Bangladesh; (M.S.H.); (N.S.); (M.R.I.); (M.E.A.)
| | - Md. Easin Arafat
- Department of Pharmacy, Faculty of Allied Health Sciences, Daffodil International University, Dhaka 1207, Bangladesh; (M.S.H.); (N.S.); (M.R.I.); (M.E.A.)
| | - Shukanta Bhowmik
- Department of Applied Chemistry, Graduate School of Engineering, University of Hyogo, 2167 Shosha, Himeji 671-2280, Hyogo, Japan; (M.H.-O.-R.); (M.N.A.); (S.B.)
| | - Shin-ichi Yusa
- Department of Applied Chemistry, Graduate School of Engineering, University of Hyogo, 2167 Shosha, Himeji 671-2280, Hyogo, Japan; (M.H.-O.-R.); (M.N.A.); (S.B.)
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Müller-Lierheim WGK. Why Chain Length of Hyaluronan in Eye Drops Matters. Diagnostics (Basel) 2020; 10:E511. [PMID: 32717869 PMCID: PMC7459843 DOI: 10.3390/diagnostics10080511] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2020] [Revised: 07/11/2020] [Accepted: 07/20/2020] [Indexed: 02/06/2023] Open
Abstract
The chain length of hyaluronan (HA) determines its physical as well as its physiological properties. Results of clinical research on HA eye drops are not comparable without this parameter. In this article methods for the assessment of the average molecular weight of HA in eye drops and a terminology for molecular weight ranges are proposed. The classification of HA eye drops according to their zero shear viscosity and viscosity at 1000 s-1 shear rate is presented. Based on the gradient of mucin MUC5AC concentration within the mucoaqueous layer of the tear film a hypothesis on the consequences of this gradient on the rheological properties of the tear film is provided. The mucoadhesive properties of HA and their dependence on chain length are explained. The ability of HA to bind to receptors on the ocular epithelial cells, and in particular the potential consequences of the interaction between HA and the receptor HARE, responsible for HA endocytosis by corneal epithelial cells is discussed. The physiological function of HA in the framework of ocular surface homeostasis and wound healing are outlined, and the influence of the chain length of HA on the clinical performance of HA eye drops is illustrated. The use of very high molecular weight HA (hylan A) eye drops as drug vehicle for the next generation of ophthalmic drugs with minimized side effects is proposed and its advantages elucidated. Consequences of the diagnosis and treatment of ocular surface disease are discussed.
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Schattling P, Taipaleenmäki E, Zhang Y, Städler B. A Polymer Chemistry Point of View on Mucoadhesion and Mucopenetration. Macromol Biosci 2017; 17. [PMID: 28675773 DOI: 10.1002/mabi.201700060] [Citation(s) in RCA: 54] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2017] [Revised: 06/07/2017] [Indexed: 12/20/2022]
Abstract
Although oral is the preferred route of administration of pharmaceutical formulations, the long-standing challenge for medically active compounds to efficiently cross the mucus layer barrier limits its wider applicability. Efforts in nanomedicine to overcome this hurdle consider mucoadhesive and mucopenetrating drug carriers by selectively designing (macromolecular) building blocks. This review highlights and critically discusses recent strategies developed in this context including poly(ethylene glycol)-based modifications, cationic and thiolated polymers, as well as particles with high charge density, zeta-potential shifting ability, or mucolytic properties. The latest advances in ex vivo test platforms are also reviewed.
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Affiliation(s)
- Philipp Schattling
- Interdisciplinary Nanoscience Center (iNANO), Aarhus University, Gustav-Wieds Vej 14, 8000, Aarhus, Denmark
| | - Essi Taipaleenmäki
- Interdisciplinary Nanoscience Center (iNANO), Aarhus University, Gustav-Wieds Vej 14, 8000, Aarhus, Denmark
| | - Yan Zhang
- Interdisciplinary Nanoscience Center (iNANO), Aarhus University, Gustav-Wieds Vej 14, 8000, Aarhus, Denmark
| | - Brigitte Städler
- Interdisciplinary Nanoscience Center (iNANO), Aarhus University, Gustav-Wieds Vej 14, 8000, Aarhus, Denmark
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Sudre G, Hourdet D, Creton C, Cousin F, Tran Y. Probing pH-responsive interactions between polymer brushes and hydrogels by neutron reflectivity. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2014; 30:9700-9706. [PMID: 25099624 DOI: 10.1021/la501568p] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
We investigated the effect of specific interactions on the structure of interfaces between a brush and a hydrogel on the polymer chain length scale. We used a model system for which the interactions between the brush and the gel are switchable. We synthesized weak polyelectrolyte brushes of poly(acrylic acid) and hydrogels of polyacrylamide and poly(N,N-dimethylacrylamide) which interact solely when the poly(acrylic acid) is mainly in its acidic form. The monomer density profiles of the poly(acrylic acid) brush immersed in pure deuterium oxide (D2O) or in contact with a D2O-swollen gel were determined by neutron reflectivity. At pH 2 when the brush is in its neutral form, it interacts with the gel by hydrogen bonds while at pH 9 when the brush is a polyelectrolyte it is not interacting with the gel. Our results show that the presence of interactions with the gel at pH 2 increases the swelling ratio of the brush relative to that in pure D2O, meaning that the brushes exhibit conformations which are more extended from the surface than in the absence of interactions.
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Affiliation(s)
- Guillaume Sudre
- Laboratoire de Science et Ingénierie de la Matière Molle, UMR 7615 CNRS/UPMC/ESPCI ParisTech, 10 rue Vauquelin, F-75231 Paris Cedex 5, France
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Sudre G, Hourdet D, Cousin F, Creton C, Tran Y. Structure of surfaces and interfaces of poly(N,N-dimethylacrylamide) hydrogels. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2012; 28:12282-12287. [PMID: 22823739 DOI: 10.1021/la301417x] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/01/2023]
Abstract
We investigated the surface structure of hydrogels of poly(N,N-dimethylacrylamide) (PDMA) hydrogels synthesized and cross-linked simultaneously by redox free radical polymerization. We demonstrate the existence of a less cross-linked layer at the surface of the gel at least at two different length scales characterized by shear rheology and by neutron reflectivity, suggesting the existence of a gradient in cross-linking. The composition of the layer is shown to depend on the degree of hydrophobicity of the mold surface and is weaker for more hydrophobic molds. While the macroscopic tests proved the existence of a relatively thick under-cross-linked layer, we also demonstrated by neutron reflectivity that the gel surface at the submicrometric scale (500 nm) was also affected by the surface treatment of the mold. These results should have important implications for the measurement of macroscopic surface properties of these hydrogels such as friction or adhesion.
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Affiliation(s)
- Guillaume Sudre
- Laboratoire de Sciences et Ingénierie de la Matière Molle, UMR 7615 CNRS/UPMC/ESPCI ParisTech, Paris, France
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Advanced molecular design of biopolymers for transmucosal and intracellular delivery of chemotherapeutic agents and biological therapeutics. J Control Release 2011; 155:119-27. [PMID: 21699934 DOI: 10.1016/j.jconrel.2011.06.009] [Citation(s) in RCA: 40] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2011] [Revised: 05/21/2011] [Accepted: 06/03/2011] [Indexed: 12/22/2022]
Abstract
Hydrogels have been instrumental in the development of polymeric systems for controlled release of therapeutic agents. These materials are attractive for transmucosal and intracellular drug delivery because of their facile synthesis, inherent biocompatibility, tunable physicochemical properties, and capacity to respond to various physiological stimuli. In this contribution, we outline a multifaceted hydrogel-based approach for expanding the range of therapeutics in oral formulations from classical small-molecule drugs to include proteins, chemotherapeutics, and nucleic acids. Through judicious material selection and careful design of copolymer composition and molecular architecture, we can engineer systems capable of responding to distinct physiological cues, with tunable physicochemical properties that are optimized to load, protect, and deliver valuable macromolecular payloads to their intended site of action. These hydrogel carriers, including complexation hydrogels, tethered hydrogels, interpenetrating networks, nanoscale hydrogels, and hydrogels with decorated structures are investigated for their ability to respond to changes in pH, to load and release insulin and fluorescein, and remain non-toxic to Caco-2 cells. Our results suggest these novel hydrogel networks have great potential for controlled delivery of proteins, chemotherapeutics, and nucleic acids.
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Abstract
The engineering of materials that can modulate the immune system is an emerging field that is developing alongside immunology. For therapeutic ends such as vaccine development, materials are now being engineered to deliver antigens through specific intracellular pathways, allowing better control of the way in which antigens are presented to one of the key types of immune cell, T cells. Materials are also being designed as adjuvants, to mimic specific 'danger' signals in order to manipulate the resultant cytokine environment, which influences how antigens are interpreted by T cells. In addition to offering the potential for medical advances, immunomodulatory materials can form well-defined model systems, helping to provide new insight into basic immunobiology.
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Tyliszczak B, Polaczek J, Pielichowski J, Pielichowski K. Preparation and Properties of Biodegradable Slow-Release PAA Superabsorbent Matrixes for Phosphorus Fertilizers. ACTA ACUST UNITED AC 2009. [DOI: 10.1002/masy.200950534] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
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Peppas NA, Thomas JB, McGinty J. Molecular aspects of mucoadhesive carrier development for drug delivery and improved absorption. JOURNAL OF BIOMATERIALS SCIENCE-POLYMER EDITION 2009; 20:1-20. [PMID: 19105897 DOI: 10.1163/156856208x393464] [Citation(s) in RCA: 54] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Although the oral route remains the most favored route of drug administration, major scientific obstacles prevent the effective and efficient delivery of low-molecular-mass drugs, peptides and proteins that exhibit poor solubility and permeability. Mucoadhesive dosage forms and the associated drug carriers have the ability to interact at a molecular level with the mucus gel layer that lines the epithelial surfaces of the major absorptive regions of the body. This interaction provides an increased residence time of the therapeutic formulation while localizing the drug at the site of administration. Such local, non-specific targeting leads to an increase in both oral absorption and bioavailability. Fundamental understanding of the biological processes encountered along the gastrointestinal tract can provide a sufficient engineer of carriers that are capable to provide this increase in residence time. Here we discuss the theoretical framework for achieving mucoadhesive systems as related to biomaterials science and the structure of the biomaterials used.
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Affiliation(s)
- Nicholas A Peppas
- Departments of Chemical and Biomedical Engineering and Division of Pharmaceutics, The University of Texas at Austin, 1 University Station, C0400, CPE 3.468, Austin, TX 78712, USA.
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Yang T, Zaman MH. Cell adhesion to nanoligands: effects of ligand size and concentration in solution. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2008; 24:11819-11827. [PMID: 18816080 DOI: 10.1021/la801885c] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/26/2023]
Abstract
Cells interact with both tethered and motile ligands in their extracellular environment to initiate and regulate signaling, adhesion, and migration. A quantitative and fundamental understanding of these receptor-ligand interactions is necessary for drug discovery, tissue engineering, and biomaterial fabrication. In this paper, we present a mean field approach to quantify the fundamental thermodynamics of interaction between the cell surface receptors and motile ligands in solvent. Our studies show that the free energy of interaction between the receptors and the nanosized ligands depends strongly on the ligand size and the effects at lower and higher concentrations show completely opposite trends that cannot be explained by simple scaling laws. In addition, we also observe various regimes of strong and weak adhesion as a function of ligand size and concentration. Our calculations provide insights into understanding cell-matrix interactions at a fundamental level as well as to identify potential avenues for fabrication of nanoligands for therapeutic and biotechnological purposes.
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Affiliation(s)
- Tianyi Yang
- Department of Physics, and Institute for Theoretical Chemistry, The University of Texas at Austin, Austin, Texas 78712, USA
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Serra L, Doménech J, Peppas NA. Engineering design and molecular dynamics of mucoadhesive drug delivery systems as targeting agents. Eur J Pharm Biopharm 2008; 71:519-28. [PMID: 18976706 DOI: 10.1016/j.ejpb.2008.09.022] [Citation(s) in RCA: 140] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2008] [Revised: 07/17/2008] [Accepted: 09/02/2008] [Indexed: 10/21/2022]
Abstract
The goal of this critical review is to provide a critical analysis of the chain dynamics responsible for the action of micro- and nanoparticles of mucoadhesive biomaterials. The objective of using bioadhesive controlled drug delivery devices is to prolong their residence at a specific site of delivery, thus enhancing the drug absorption process. These mucoadhesive devices can protect the drug during the absorption process in addition to protecting it on its route to the delivery site. The major emphasis of recent research on mucoadhesive biomaterials has been on the use of adhesion promoters, which would enhance the adhesion between synthetic polymers and mucus. The use of adhesion promoters such as linear or tethered polymer chains is a natural result of the diffusional characteristics of adhesion. Mucoadhesion depends largely on the structure of the synthetic polymer gels used in controlled release applications.
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Affiliation(s)
- Laura Serra
- Biomaterials, Drug Delivery, Bionanotechnology and Molecular Recognition Laboratories, University of Texas at Austin, Austin, TX 78712, USA
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Yang T, Zaman MH. Thermodynamics of clustered and unclustered receptor systems in cell adhesion. Chem Phys Lett 2008. [DOI: 10.1016/j.cplett.2008.01.088] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
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Brock Thomas J, Tingsanchali JH, Rosales AM, Creecy CM, McGinity JW, Peppas NA. Dynamics of Poly(ethylene glycol)-Tethered, pH Responsive Networks. POLYMER 2007; 48:5042-5048. [PMID: 18690288 DOI: 10.1016/j.polymer.2007.06.035] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Smart biomaterials composed of pH responsive polymers, poly((meth)acrylic acid), were synthesized using a precipitation polymerization technique. The microparticles were grafted with poly(ethylene glycol) (PEG) chains that are capable of complexing with the hydroxyl groups of the polyacid and interpenetrating into the mucus gel layer upon entry into the small intestine. Upon introduction of an alkaline solution, these materials imbibe a significant amount of water and create a highly viscous suspension. These materials have the necessary physicochemical properties to serve as mucoadhesive controlled release drug carriers for the oral delivery of drugs.
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Affiliation(s)
- J Brock Thomas
- Department of Chemical Engineering, The University of Texas at Austin, 1 University Station, C0400, Austin, TX 78712-1062, USA
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Abstract
Receptor-mediated cell adhesion plays a critical role in cell migration, proliferation, signaling, and survival. A number of diseases, including cancer, show a strong correlation between integrin activation and metastasis. A better understanding of cell adhesion is highly desirable for not only therapeutic but also a number of tissue engineering applications. While a number of computational models and experimental studies have addressed the issue of cell adhesion to surfaces, no model or theory has adequately addressed cell adhesion at the molecular level. In this paper, the authors present a thermodynamic model that addresses receptor-mediated cell adhesion at the molecular level. By incorporating the entropic, conformational, solvation, and long- and short-range interactive components of receptors and the extracellular matrix molecules, they are able to predict adhesive free energy as a function of a number of key variables such as surface coverage, interaction distance, molecule size, and solvent conditions. Their method allows them to compute the free energy of adhesion in a multicomponent system where they can simultaneously study adhesion receptors and ligands of different sizes, chemical identities, and conformational properties. The authors' results not only provide a fundamental understanding of adhesion at the molecular level but also suggest possible strategies for designing novel biomaterials.
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Affiliation(s)
- Tianyi Yang
- Department of Physics, The University of Texas at Austin, Austin, Texas 78712, USA
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Serra L, Doménech J, Peppas NA. Design of poly(ethylene glycol)-tethered copolymers as novel mucoadhesive drug delivery systems. Eur J Pharm Biopharm 2005; 63:11-8. [PMID: 16368228 DOI: 10.1016/j.ejpb.2005.10.011] [Citation(s) in RCA: 85] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2005] [Accepted: 10/25/2005] [Indexed: 10/25/2022]
Abstract
We developed novel acrylic-based polymers that can be used as mucoadhesive delivery systems. Poly(acrylic acid) hydrogels were modified by grafting adhesion promoter chains such as poly(ethylene glycol) (PEG) onto their back-bone chains, thus promoting the adhesive process by interpenetration. The copolymers synthesized were designated as P(AA-g-EG). Hydrogels were synthesized using PEG of two different molecular weights, 1000 and 2000, and with varying molar feed ratio of AA-EG (20:80, 40:60, 60:40, 80:20, 12:88, 25:75, 44:56, 67:33). The copolymers were synthesized by using free radical solution UV-polymerization. The effects of different PEG-tethered structures on mucoadhesion were studied using a tensiometric testing and the work of adhesion was calculated. Preswollen P(AA-g-EG) copolymer films composed of 40% acrylic acid (AA) and 60% ethylene glycol (EG), containing PEG 1000 tethers, exhibited the highest value for the work of mucoadhesion, 130 x 10(-3)+/-27 x 10(-3) mJ, that is five times higher than the formulation composed of pure PAA. Based on these results and associated molecular analysis, we conclude that the higher mucoadhesive properties of this specific copolymer were the result of the synergistic effects of both monomers. AA functional groups allowed the polymer to form multiple hydrogen bonds with the glycoproteins present in the mucus. PEG tethers possibly acted as mucoadhesive promoters, enhancing interpenetration of polymer chains into the mucus.
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Affiliation(s)
- Laura Serra
- Biomaterials, Drug Delivery, Bionanotechnology and Molecular Recognition Laboratories, University of Texas at Austin, Austin, TX 78712, USA
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Peppas NA, Huang Y. Nanoscale technology of mucoadhesive interactions. Adv Drug Deliv Rev 2004; 56:1675-87. [PMID: 15350296 DOI: 10.1016/j.addr.2004.03.001] [Citation(s) in RCA: 151] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2004] [Accepted: 05/15/2004] [Indexed: 11/29/2022]
Abstract
Nanoscale analysis may be used to design new types of mucoadhesive polymers. Understanding of the surface interactions between hydrophilic polymer surfaces and mucins can lead to improved adhesive bonding by hydrogen bonding. Alternatively, decoration of a mucoadhesive polymer surface with tethers of linear and block copolymers containing neutral or ionizable structures provides increased interdigitation and interpenetration with the mucus. Finally, formation of micro- or nanopatterns on these surfaces can lead to promising new systems of oral delivery applications.
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Affiliation(s)
- Nicholas A Peppas
- Department of Chemical Engineering, CPE 3.466, 1 University Station, C-0400, The University of Texas at Austin, Austin, TX 78712-0231, USA.
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VICTOROV AI, RADKE CJ, PRAUSNITZ JM. Molecular thermodynamics for swelling of a bicontinuous gel. Mol Phys 2002. [DOI: 10.1080/00268970210132531] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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Bures P, Huang Y, Oral E, Peppas NA. Surface modifications and molecular imprinting of polymers in medical and pharmaceutical applications. J Control Release 2001; 72:25-33. [PMID: 11389982 DOI: 10.1016/s0168-3659(01)00259-0] [Citation(s) in RCA: 142] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
Abstract
Recent developments in the field of biomaterials are based on molecular design of polymers with improved surface and bulk properties. Novel techniques of surface modification by addition of tethered chains can lead to materials with the ability to recognize biological and pharmaceutical compounds. Methods based on molecular imprinting can increase the recognition capabilities of such systems. Chain tethering can also can improve the mucoadhesive behavior of a delivery device and the effectiveness of a drug by allowing targeting and localization of a drug at a specific site. Acrylic-based hydrogels are well-suited for mucoadhesion due to their flexibility and nonabrasive characteristics which reduce damage-causing attrition to the tissues in contact. However, the adhesive and drug delivery capabilities of these devices can continue to be improved as presently known bioadhesive materials are modified and more bioadhesive materials are discovered. Tethering of long PEG chains on PAA hydrogels and their copolymers can be achieved by grafting reactions involving thionyl chloride, followed by PEG grafting. The ensuing materials exhibit mucoadhesive properties due to enhanced anchoring of the chains with the mucosa. Theoretical calculations can lead to optimization of the tethered structure.
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Affiliation(s)
- P Bures
- Program on Therapeutic and Diagnostic Devices, Biomaterials and Drug Delivery Laboratories, School of Chemical Engineering, Purdue University, 1283 Chemical Engineering Building (CHME), West Lafayette, IN 47907-1283, USA
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