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Iijima K, Kimura T, Sato R, Takahashi T, Hashizume M. Kinetic Analysis of Molecular Permeabilities of Free-Standing Polysaccharide Composite Films. MACROMOL CHEM PHYS 2016. [DOI: 10.1002/macp.201600391] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Affiliation(s)
- Kazutoshi Iijima
- Department of Industrial Chemistry; Faculty of Engineering; Tokyo University of Science; 12-1 Ichigayafunagawara-machi Shinjuku-ku Tokyo 162-0826 Japan
- Graduate School of Chemical Sciences and Technology; Tokyo University of Science; 12-1 Ichigayafunagawara-machi Shinjuku-ku Tokyo 162-0826 Japan
| | - Takayuki Kimura
- Graduate School of Chemical Sciences and Technology; Tokyo University of Science; 12-1 Ichigayafunagawara-machi Shinjuku-ku Tokyo 162-0826 Japan
| | - Ryo Sato
- Department of Industrial Chemistry; Faculty of Engineering; Tokyo University of Science; 12-1 Ichigayafunagawara-machi Shinjuku-ku Tokyo 162-0826 Japan
| | - Tomoki Takahashi
- Graduate School of Engineering; Kobe University; 1-1 Rokkodai-cho Nada-ku Kobe 657-8501 Japan
| | - Mineo Hashizume
- Department of Industrial Chemistry; Faculty of Engineering; Tokyo University of Science; 12-1 Ichigayafunagawara-machi Shinjuku-ku Tokyo 162-0826 Japan
- Graduate School of Chemical Sciences and Technology; Tokyo University of Science; 12-1 Ichigayafunagawara-machi Shinjuku-ku Tokyo 162-0826 Japan
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2
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Saha NR, Sarkar G, Roy I, Rana D, Bhattacharyya A, Adhikari A, Mukhopadhyay A, Chattopadhyay D. Studies on methylcellulose/pectin/montmorillonite nanocomposite films and their application possibilities. Carbohydr Polym 2015; 136:1218-27. [PMID: 26572465 DOI: 10.1016/j.carbpol.2015.10.046] [Citation(s) in RCA: 54] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2015] [Revised: 10/12/2015] [Accepted: 10/13/2015] [Indexed: 10/22/2022]
Abstract
Films based on methylcellulose (MC) and pectin (PEC) of different ratios were prepared. MC/PEC (90:10) (MP10) gave the best results in terms of mechanical properties. Sodium montmorillonite (MMT) (1, 3 and 5 wt%) was incorporated in the MP10 matrix. The resulting films were characterized by X-ray diffraction and transmission electron microscopy, and it was found that nanocomposites were intercalated in nature. Mechanical studies established that addition of 3 wt% MMT gave best results in terms of mechanical properties. However, thermo-gravimetric and dynamic mechanical analysis proved that decomposition and glass transition temperature increased with increasing MMT concentration from 1 to 5 wt%. It was also observed that moisture absorption and water vapor permeability studies gave best result in the case of 3 wt% MMT. Optical clarity of the nanocomposite films was not much affected with loading of MMT. In vitro drug release studies showed that MC/PEC/MMT based films can be used for controlled transdermal drug delivery applications.
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Affiliation(s)
- Nayan Ranjan Saha
- Department of Polymer Science and Technology, University of Calcutta, 92 A.P.C. Road, Kolkata 700009, India
| | - Gunjan Sarkar
- Department of Polymer Science and Technology, University of Calcutta, 92 A.P.C. Road, Kolkata 700009, India
| | - Indranil Roy
- Department of Polymer Science and Technology, University of Calcutta, 92 A.P.C. Road, Kolkata 700009, India
| | - Dipak Rana
- Department of Chemical and Biological Engineering, Industrial Membrane Research Institute, University of Ottawa, 161 Louis Pasteur St. , Ottawa, ON K1N 6N5, Canada
| | - Amartya Bhattacharyya
- Department of Polymer Science and Technology, University of Calcutta, 92 A.P.C. Road, Kolkata 700009, India
| | - Arpita Adhikari
- Department of Polymer Science and Technology, University of Calcutta, 92 A.P.C. Road, Kolkata 700009, India
| | - Asis Mukhopadhyay
- Department of Jute and Fiber Technology, Institute of Jute Technology, University of Calcutta, 35 Ballygunge Circular Road, Kolkata 700019, India
| | - Dipankar Chattopadhyay
- Department of Polymer Science and Technology, University of Calcutta, 92 A.P.C. Road, Kolkata 700009, India.
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3
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Abioye AO, Issah S, Kola-Mustapha AT. Ex vivo skin permeation and retention studies on chitosan-ibuprofen-gellan ternary nanogel prepared by in situ ionic gelation technique--a tool for controlled transdermal delivery of ibuprofen. Int J Pharm 2015; 490:112-30. [PMID: 25997660 DOI: 10.1016/j.ijpharm.2015.05.030] [Citation(s) in RCA: 61] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2015] [Revised: 05/06/2015] [Accepted: 05/11/2015] [Indexed: 01/06/2023]
Abstract
The chemical potentials of drug-polymer electrostatic interaction have been utilized to develop a novel ternary chitosan-ibuprofen-gellan nanogel as controlled transdermal delivery tool for ibuprofen. The ternary nanogels were prepared by a combination of electrostatic nanoassembly and ionic gelation techniques. The electrostatic and hydrophobic interactions as well as hydrogen bonding between ibuprofen and chitosan were confirmed with FTIR, while DSC, TGA and SEM confirmed the physical state, thermal and morphological characteristics, respectively. The ex vivo delivery of ibuprofen onto and across the skin was evaluated based on system specific drug release parameters such as steady state permeation rate, permeability coefficient, permeability enhancement ratio, skin/gel partition coefficient, diffusion coefficient, lag time and release rate constant and mechanisms of release were determined using mathematical models. Interaction between ibuprofen and chitosan produced new spherical eutectic nanoconjugates with remarkable decrease in particle size of ibuprofen from 4580 (length-to-breadth aspect ratio) to a minimum of 14.15 nm (324-times), and thermally stable amorphous characteristics. The nanogels exhibited significant elastic and pseudoplastic characteristics dictated by the concentration of chitosan with maximum swelling capacity of 775% w/w at 6.55 mM chitosan compared with 281.16 and 506.50% for plain gellan and control ibuprofen hydrogel, respectively. Chitosan enhanced the skin penetration, permeability and the rate of transdermal release of ibuprofen by a factor of 4, dictated by the extent of ibuprofen-chitosan ionic interaction and its concentration. The major mechanism of ibuprofen release through the pig skin was drug diffusion however drug partition and matrix erosion also occurred. It was evident that ternary nanogels are novel formulations with potential application in controlled transdermal delivery of ibuprofen.
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Affiliation(s)
- Amos Olusegun Abioye
- Leicester School of Pharmacy, De Montfort University, The Gateway, Leicester LE1 9BH, UK.
| | - Sureya Issah
- Leicester School of Pharmacy, De Montfort University, The Gateway, Leicester LE1 9BH, UK
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4
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Borden BA, Yockman J, Kim SW. Thermoresponsive hydrogel as a delivery scaffold for transfected rat mesenchymal stem cells. Mol Pharm 2010; 7:963-8. [PMID: 20583814 DOI: 10.1021/mp100094k] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
The concept of stem cells as a therapeutic agent has been gaining momentum. A common mode of administration of these cells is by direct injection into the target tissue. This can result in many of the cells being lost due to reflux from the injection site leading to a local loss of implanted cells. PoligoGel is a nontoxic hydrogel with an LCST near body temperature. It is also shown to be nontoxic to multiple cell types, and in the case of rat mesenchymal stem cells does not alter their differentiative capacity, either by inducing differentiation, or limiting the potential for subsequent differentiation after removal from the gel. Embedding cells in PoligoGel also does not interfere with the cells' ability to delivery therapeutic growth factors post transfection with plasmid DNA. Here a thermoresponsive hydrogel, PoligoGel, is shown to have potential to act as a scaffold for the retention of cells at an injection site, mitigating migration or washing of the cells away from the target site after implantation.
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Affiliation(s)
- Bradley A Borden
- Department of Bioengineering and Center for Controlled Chemical Delivery, University of Utah, Salt Lake City, Utah 84116, USA
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5
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An improved approach for determining permeability and diffusivity relevant to controlled release. Chem Eng Sci 2010. [DOI: 10.1016/j.ces.2010.08.028] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
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6
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Jun HW, Bayoumi SM. A Diffusion Model for Studying the Drug Release from Semisolid Dosage Forms I. Methodology Using Agar Gel as Diffusion Medium. Drug Dev Ind Pharm 2008. [DOI: 10.3109/03639048609048046] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
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7
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Affiliation(s)
- R. LANGER
- a Department of Nutrition and Food Science , M.I.T. , Cambridge, Massachusetts, 02139,#253-3107
- b Department of Surgery , Children's Hospital Medical Center , Boston, Massachusetts, 02115, #734-6000x3508
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8
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Wang LC, Chen XG, Yu LJ, Li PW. Controlled drug release through carboxymethyl-chitosan/poly(vinyl alcohol) blend films. POLYM ENG SCI 2007. [DOI: 10.1002/pen.20823] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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9
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Langer R, Peppas N. Chemical and Physical Structure of Polymers as Carriers for Controlled Release of Bioactive Agents: A Review. ACTA ACUST UNITED AC 2006. [DOI: 10.1080/07366578308079439] [Citation(s) in RCA: 214] [Impact Index Per Article: 11.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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10
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Ofori-Kwakye K, Fell JT. Biphasic drug release: the permeability of films containing pectin, chitosan and HPMC. Int J Pharm 2001; 226:139-45. [PMID: 11532577 DOI: 10.1016/s0378-5173(01)00802-x] [Citation(s) in RCA: 49] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
Abstract
The permeabilities of mixed films of pectin/chitosan/HPMC have been studied to assess their value in producing a dosage form with biphasic drug release characteristics. The inclusion of chitosan enhanced the properties of the films, rendering them stable at all physiological pH values. Pectin/HPMC films were soluble at pH values above 3.0. All pectin/chitosan/HPMC films were permeable to a model drug, paracetamol. HPMC initially increased the permeability of the films and subsequently reduced it at higher concentrations. The minimum permeability was obtained at pH 3 and at an HPMC level of 5% where the potential for polyelectrolyte complex formation between pectin and chitosan exists. The permeabilities of the films increased when they were exposed to pectinolytic enzymes, a system designed to mimic conditions in the colon. The film formulation thus show the potential for biphasic delivery with an initial, controllable slow phase that can be manipulated by changes in the formulation followed by a faster phase under conditions pertaining in the colon.
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Affiliation(s)
- K Ofori-Kwakye
- School of Pharmacy and Pharmaceutical Sciences, University of Manchester, Manchester M13 9PL, UK
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11
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Macleod GS, Collett JH, Fell JT. The potential use of mixed films of pectin, chitosan and HPMC for bimodal drug release. J Control Release 1999; 58:303-10. [PMID: 10099155 DOI: 10.1016/s0168-3659(98)00168-0] [Citation(s) in RCA: 80] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
Abstract
Polyelectrolyte complex (PEC) formation between pectin USP and chitosan was investigated by examining the viscosities of supernatant solutions after removal of the precipitated complex. The amount of pectin, relative to chitosan, required for optimal PEC formation increased as the pH of the solution was reduced. At pH values of less than 1.3, there was no evidence for the formation of the PEC. Swelling studies conducted on pectin/chitosan films, showed minimal swelling occurring when the pectin:chitosan weight ratio was optimal for PEC formation, suggesting the formation of the PEC in situ. The permeability of the films to paracetamol as a model compound was dependent on film composition and was markedly increased after exposure to pectinolytic enzymes, used to mimic conditions in the colon. It may be implied from the results that similar formulations, applied as a film coat to tablets, could be used to achieve bimodal drug release with colonic conditions acting as a trigger for an increased rate of release.
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Affiliation(s)
- G S Macleod
- School of Pharmacy and Pharmaceutical Sciences, University of Manchester, Manchester M13 9PL, UK
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12
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Abstract
Developing hydrogel membranes and coatings of appropriate permeability characteristics is key to the success of a number bioartificial organ technologies. Key principles relevant to the design and application of hydrogels for such applications were reviewed. The first key point is that permeability is a function of both transport and thermodynamic properties, the diffusion coefficient and partition coefficient, respectively, and that these parameters can be evaluated separately. Although the aspect of partitioning often emphasized is size exclusion, this review points out that many other relevant interactions come into play, especially hydrophobic and electrostatic interactions, and that these phenomena can dominate size exclusion. Similarly, while the diffusion coefficient also is strongly dependent upon size, other interactions can also cause diffusivity to deviate from theories which consider only solute size and gel swelling. For example, the heterogeneity of hydrogel networks can result in permeabilities that fail to decline as much as might be anticipated if networks were uniform.
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Affiliation(s)
- S H Gehrke
- Department of Chemical Engineering, University of Cincinnati, Ohio 45221-0171, USA.
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13
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Tejima T, Jalsenjak I, Kondo T. Permeability to solutes of polyamide capsules with different chemical compositions. J Microencapsul 1996; 13:377-84. [PMID: 8808775 DOI: 10.3109/02652049609026024] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
The permeability of nylon capsule membranes with different chemical compositions to solutes was studied at different temperatures. The rate of solute permeation through the membrane decreased with increasing hydrophobicity of the membrane in the temperature range of 293-323 K. Increase in the size of permeant molecules caused a decreased in their rate of permeation through all capsule membranes at all temperatures studied. Higher permeation rates were observed for all permeants at higher temperatures. The activation energy of permeation was evaluated for the permeants from the Arrhenius plots of their permeation data. From the values of activation energy evaluated the solute permeation through the nylon capsule membranes was demonstrated to proceed by a pore mechanism.
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Affiliation(s)
- T Tejima
- Faculty of Pharmaceutical Sciences, Science University of Tokyo, Japan
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14
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El-Gibaly I, Safwat SM, Ahmed MO. Microencapsulation of ketoprofen using w/o/w complex emulsion technique. J Microencapsul 1996; 13:67-87. [PMID: 8903786 DOI: 10.3109/02652049609006804] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
Sustained release cellulose acetate butyrate (CAB)-polystyrene (PS) microcapsules containing ketoprofen (a non-steroidal anti-inflammatory drug) were prepared adopting the modified W/O/W complex emulsion technique. The effect of polystyrene concentration and core/coat ratio on the yield, geometric mean particle diameter, dg, size distribution, drug loading as well as release and surface characteristics of the microcapsules was investigated. The results obtained revealed that polystyrene utilization as a wall material plays a dominant role in the manufacturing process. A particular composition of 92 center dot 5: 7 center dot 5 (%) of CAB to PS was found to improve greatly the microcapsule yield and maximize the drug loading. In most cases, the encapsulation efficiencies increased with increasing microcapsule size and theoretical drug loading. Kinetic analysis of the data shows that the drug release process from CAB microcapsules followed Higuchi model (a diffusion-controlled model for a planar matrix), whereas the release behaviour conforms with Baker and Lonsdale model (a diffusion-controlled model for a spherical matrix) for CAB-PS microcapsules. The preparation of free films of CAB and CAB-PS was described for comparison. The effect of processing parameters (polystyrene concentration, total polymers concentration and permeant concentration) on the permeation of ketoprofen through the polymeric films was discussed. The results demonstrated that ketoprofen permeation through the films and microcapsules could be controlled by modifying the CAB-PS ratio in the polymer matrices. The permeability constants lowered with increasing total polymers concentration up to 5% and were proportional to permeant concentration. To compare the kinetics of drug release from polymeric films with those of microcapsules, ketoprofen was incorporated at different concentrations within CAB-PS cast films. These films exhibited sustained release of the drug (t0 center dot 5; 58-146 h). Release rates were found to agree with the Baker and Lonsdale model, previously suggested for ketoprofen release from CAB-PS microcapsules.
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Affiliation(s)
- I El-Gibaly
- Pharmaceutics Department, Assiut University, Egypt
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15
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Yang Y, Jacobs H, Bae YH, Kim SW. Selective protein transport through a thin cellulose coated porous membrane. Biotechnol Bioeng 1994; 43:207-14. [DOI: 10.1002/bit.260430304] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
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16
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17
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Dong LC, Hoffman AS, Yan Q. Dextran permeation through poly(N-isopropylacrylamide) hydrogels. JOURNAL OF BIOMATERIALS SCIENCE. POLYMER EDITION 1994; 5:473-84. [PMID: 7518690 DOI: 10.1163/156856294x00158] [Citation(s) in RCA: 36] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
The permeation of macromolecules such as fluoroescein-labeled dextran fractions through thermally reversible hydrogels has been investigated. A permeation model has been formulated, which takes into account hydrogel porosity and tortuosity as well as the combined effect of a geometric restraint for a relatively large solute molecule at a pore entrance and the friction between solute molecules moving through the pores and pore walls. Based on this model, we have estimated the tortuosity and average pore size of a swollen hydrogel, poly(N-isopropylacrylamide) [poly(NIPAAm)] and a swollen heterogel, poly(N-isopropylacrylamide-co-vinyl-terminated dimethylsiloxane) [poly(NIPAAm-co-VTPDMS)]. The permeation data for dextran molecules up to the size of 43.5 A in radius show good agreement with the values predicted from the model.
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18
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Carelli V, Di Colo G, Nannipieri E, Serafini MF. A study of controlled-release systems for progesterone based on crosslinked poly(ethylene oxides). Int J Pharm 1993. [DOI: 10.1016/0378-5173(93)90014-7] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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19
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20
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Moeckly DM, Matheson LE. The development of a predictive method for the estimation of flux through polydimethylsiloxane membranes: I. Identification of critical variables for a series of substituted benzenes. Int J Pharm 1991. [DOI: 10.1016/0378-5173(91)90312-c] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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21
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Blanchon S, Couarraze G, Rieg-Falson F, Cohen G, Puisieux F. Permeability of progesterone and a synthetic progestin through methacrylic films. Int J Pharm 1991. [DOI: 10.1016/0378-5173(91)90374-w] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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22
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Dong LC, Hoffman AS. A novel approach for preparation of pH-sensitive hydrogels for enteric drug delivery. J Control Release 1991. [DOI: 10.1016/0168-3659(91)90072-l] [Citation(s) in RCA: 293] [Impact Index Per Article: 8.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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23
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Gin H, Dupuy B, Caix J, Baquey C, Ducassou D. In vitro diffusion in polyacrylamide embedded agarose microbeads. J Microencapsul 1990; 7:17-23. [PMID: 2407819 DOI: 10.3109/02652049009028420] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
125I Sodium iodide, 125I insulin, 125I albumin, and 111indium IGG were employed to investigate release from, and penetration of different sized molecules into agarose/polyacrylamide microcapsules. The microcapsules were formed by photopolymerization of an acrylamide solution round agarose beads. The indium-chelated antibody gave a particular low background count. The different release times were explained in terms of differences in diffusion coefficient. By retarding in vitro penetration of antibodies, these microcapsules could be of value for the encapsulation of living cells in bioartificial organs.
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Affiliation(s)
- H Gin
- INSERM U 306, Bordeaux, France
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24
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Castellano PM, Pastoriza MA, Martińez de Bertorello M, Bertorello HE, Horas JA. In vitro sodium salicylate release from a sucrose polyester matrix. J Pharm Sci 1989; 78:561-2. [PMID: 2778655 DOI: 10.1002/jps.2600780710] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
Sucrogel H-70, a recently synthesized polyester of sucrose, was investigated as a potential drug delivery matrix. In this study, the release of sodium salicylate was examined from a reservoir-controlled release device. It is shown that sodium salicylate release follows zero-order kinetics in the three media studied (i.e., water and simulated gastric and intestinal fluids).
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Affiliation(s)
- P M Castellano
- Departamento de Farmacia, Facultad de Ciencias Químicas, Universidad Nacional de Córdoba, Argentina
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25
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26
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Graham N, Zulfiqar M, MacDonald B, McNeill M. Caffeine release from fully swollen poly(ethylene oxide) hydrogels. J Control Release 1987. [DOI: 10.1016/0168-3659(88)90023-5] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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27
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28
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Moynihan HJ, Honey MS, Peppas NA. Solute diffusion in swollen membranes. Part V: Solute diffusion in poly(2-hydroxyethyl methacrylate). POLYM ENG SCI 1986. [DOI: 10.1002/pen.760261703] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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29
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Roorda WE, Boddé HE, De Boer AG, Bouwstra JA, Junginer HE. Synthetic hydrogels as drug delivery systems. PHARMACEUTISCH WEEKBLAD. SCIENTIFIC EDITION 1986; 8:165-89. [PMID: 3526277 DOI: 10.1007/bf01959775] [Citation(s) in RCA: 35] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
Hydrogels are widely studied materials for the preparation of sustained release drug dosage forms. Their soft, tissue-like consistency and their high biocompatibility in a number of applications make them promising candidates for this purpose. The water and the polymer in the gel form intricate structures and much research has been devoted to the elucidation of these structures, and of the interactions involved in their formation. Simple, drug-loaded hydrogels normally give a matrix-type delivery profile, in which the release rate is proportional to the square root of time; a number of approaches has been used to change this profile to other types of delivery, for instance to zero-order release. A number of in vivo tests using hydrogel delivery systems has given favourable results.
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30
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Kulkarni M, Mashelkar R. A unified approach to transport phenomena in polymeric media—II Diffusion in solid structured polymers. Chem Eng Sci 1983. [DOI: 10.1016/0009-2509(83)80015-3] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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31
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Bala K, Guha SK, Vasudevan P. p-Amino salicylic acid - oxidized cellulose system: a model for long term drug delivery. Biomaterials 1982; 3:97-100. [PMID: 7082744 DOI: 10.1016/0142-9612(82)90041-2] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
Abstract
The mobilization of p-amino salicylic acid (PASA) on periodic oxidized cellulose (O.C) as a biocompatible carrier was investigated. The immobilization of the PASA is based on Schiff's base formation between the amino group of PASA and the aldehyde group of O.C. The in vivo and in vitro release of p-amino salicylic acid was studied. Such a system may be useful for the sustained delivery of the drugs in the body, since O.C. itself is a biosoluble carrier.
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32
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Wood JM, Attwood D, Collett JH. The influence of gel formulation on the diffusion of salicylic acid in polyHEMA hydrogels. J Pharm Pharmacol 1982; 34:1-4. [PMID: 6121024 DOI: 10.1111/j.2042-7158.1982.tb04666.x] [Citation(s) in RCA: 39] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
Abstract
The influence of solute concentration, gel hydration, and crosslinking density on diffusion rates in polyHEMA hydrogels has been investigated using a radio-tracer technique. At hydrations above 31% water, diffusion is by pore flow, and increases in the crosslinking density of gels bring about a decrease in the diffusion coefficient, D. Below 31% hydration, diffusion is predominantly by solution diffusion and changes in crosslinking density have little effect on the diffusion coefficient. The diffusion coefficient is invariant with solute concentration within the range reported, although a very high solute concentration, for the gels of lower hydration, the diffusion coefficient is higher than expected. A high value for D may be due to saturation of the binding sites of the diffusant on the polymer chains, leaving a greater proportion of diffusant available for transport.
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33
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Sung YK, Gregonis DE, John MS, Andrade JD. Thermal and pulse NMR analysis of water in poly(2-hydroxyethyl methacrylate). J Appl Polym Sci 1981. [DOI: 10.1002/app.1981.070261118] [Citation(s) in RCA: 58] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
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34
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Matheson LE, Hunke WA. Mass transport properties of co(polyether)polyurethane membranes I: Preparation and characterization. J Pharm Sci 1981; 70:571-3. [PMID: 7241367 DOI: 10.1002/jps.2600700528] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
Abstract
A series of polyurethane copolymers containing polyethylene glycol 600, 1000, or 1540 was synthesized, purified by reprecipitation, and cast into clear, tough, flexible membranes using the solution method. The weight average molecular weight of each polymer was estimated by gel permeation chromatography. The ability of the various polymers to absorb water was measured and increased with the increasing molecular weight of the polyethylene-glycol. The ability of the copolymer membranes to hold a pH gradient decreased with increasing polyethylene glycol molecular weight.
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Lee E, Kim S, Kim S, Cardinal J, Jacobs H. Drug release from hydrogel devices with ratecontrolling barriers. J Memb Sci 1980. [DOI: 10.1016/s0376-7388(00)80474-3] [Citation(s) in RCA: 80] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
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Zentner GM, Cardinal JR, Gregonis DE. Progestin permeation through polymer membranes III: Polymerization solvent effect on progesterone permeation through hydrogel membranes. J Pharm Sci 1979; 68:794-5. [PMID: 458587 DOI: 10.1002/jps.2600680635] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
Hydrogels prepared from poly(hydroxyethyl methacrylate) are biocompatible and highly permeable to low molecular weight solutes. Permeation rates can be varied by altering the cross-linker concentration or using copolymers; the latter are chosen to alter the hydrogel equilibrium hydration. These factors suggest that hydrogels are good candidates for controlled-release drug delivery devices. Hydrogels may be synthesized using various temperatures, initiators (nature and concentration), and solvents (nature and concentration). This study demonstrated that progesterone permeation through poly(hydroxyethyl methacrylate) films is independent of polymerization solvent (nature and concentration) for the solvents, water, ethanol, and tert-butyl alcohol. The importance of hydrogel equilibrium hydration in progesterone permeation is emphasized.
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Zentner GM, Cardinal JR, Kim SW. Progestin permeation through polymer membranes I: diffusion studies on plasma-soaked membranes. J Pharm Sci 1978; 67:1347-51. [PMID: 702276 DOI: 10.1002/jps.2600671003] [Citation(s) in RCA: 31] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
The potential of several commercially available polymeric materials for use in controlled-release drug delivery devices was investigated. Progesterone was used as a model hydrophobic drug. The progesterone permeation rates through polydimethylsiloxane, two polyether urethanes, a hydroxyethyl methacrylate, a polyether urethan--polydimethylsiloxane blend, and a cellulosic membrane were determined. The permeabilities were obtained on nonsoaked membranes and on membranes soaked in plasma for varying times. The purpose of the plasma soaks was to examine the effects of lipid absorption and degradative processes within the membrane on progesterone permeability. This study identified several polymers that show potential for use in controlled-release drug delivery devices. The plasma treatment studies showed that several polymers may not be acceptable. The plasma soak studies were interpreted in terms of the mechanisms of drug permeation through the membranes.
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