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Sarkar Das S, Lucas AD, Carlin AS, Zheng J, Patwardhan DV, Saylor DM. Controlled initial surge despite high drug fraction and high solubility. Pharm Dev Technol 2016; 22:35-44. [PMID: 26895348 DOI: 10.3109/10837450.2015.1135341] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
Potential connections between release profiles and solvent evaporation rates alongside polymer chemistry were elucidated for the release of tetracycline hydrochloride from two different poly (d, l-lactide-co-glycolide) (PLGA) film matrices containing high drug fractions (50%, 30%, and 15%), and prepared at two distinct solvent evaporation rates. At highest tetracycline concentrations (50%), (i) the early release rates were ≤0.5 μg/min in all cases; (ii) release was linear from systems fabricated with lower lactic content and slower solvent evaporation rate and bimodal from systems fabricated with higher lactic content and faster evaporation rate; (iii) surface fractions covered by the drug were similar at both evaporation rates for 85:15 PLGA but very different for 50:50 PLGA, leading to unexpectedly reduced early release from 50:50 PLGA than from 85:15 PLGA when both the matrices were fabricated using a slower evaporation rate. These features remained unaffected in case of low drug concentration. Results suggested that during the formation of the drug-polymer microstructure, the combined effect of polymer chemistry and solvent evaporation rate sets apart the surface characteristics and the initial release profiles of systems containing high drug fraction, and an appropriate combination of these parameters may be utilized to control the early stage of drug release.
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Affiliation(s)
- Srilekha Sarkar Das
- a Office of Science and Engineering Laboratories, Center for Devices and Radiological Health and
| | - Anne D Lucas
- a Office of Science and Engineering Laboratories, Center for Devices and Radiological Health and
| | - Alan S Carlin
- b Office of Product Quality/Office of Testing and Research, Center for Drug Evaluation and Research, US Food and Drug Administration , Silver Spring , MD , USA
| | - Jiwen Zheng
- a Office of Science and Engineering Laboratories, Center for Devices and Radiological Health and
| | - Dinesh V Patwardhan
- a Office of Science and Engineering Laboratories, Center for Devices and Radiological Health and
| | - David M Saylor
- a Office of Science and Engineering Laboratories, Center for Devices and Radiological Health and
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Fox CB, Kim J, Le LV, Nemeth CL, Chirra HD, Desai TA. Micro/nanofabricated platforms for oral drug delivery. J Control Release 2015; 219:431-444. [PMID: 26244713 DOI: 10.1016/j.jconrel.2015.07.033] [Citation(s) in RCA: 67] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2015] [Revised: 07/29/2015] [Accepted: 07/30/2015] [Indexed: 12/18/2022]
Abstract
The oral route of drug administration is most preferred due to its ease of use, low cost, and high patient compliance. However, the oral uptake of many small molecule drugs and biotherapeutics is limited by various physiological barriers, and, as a result, drugs suffer from issues with low solubility, low permeability, and degradation following oral administration. The flexibility of micro- and nanofabrication techniques has been used to create drug delivery platforms designed to address these barriers to oral drug uptake. Specifically, micro/nanofabricated devices have been designed with planar, asymmetric geometries to promote device adhesion and unidirectional drug release toward epithelial tissue, thereby prolonging drug exposure and increasing drug permeation. Furthermore, surface functionalization, nanotopography, responsive drug release, motion-based responses, and permeation enhancers have been incorporated into such platforms to further enhance drug uptake. This review will outline the application of micro/nanotechnology to specifically address the physiological barriers to oral drug delivery and highlight technologies that may be incorporated into these oral drug delivery systems to further enhance drug uptake.
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Affiliation(s)
- Cade B Fox
- Department of Bioengineering and Therapeutic Sciences, University of California, San Francisco, CA 94158, USA
| | - Jean Kim
- UC Berkeley & UCSF Graduate Program in Bioengineering, UCSF Mission Bay Campus, San Francisco, CA 94158, USA
| | - Long V Le
- UC Berkeley & UCSF Graduate Program in Bioengineering, UCSF Mission Bay Campus, San Francisco, CA 94158, USA
| | - Cameron L Nemeth
- UC Berkeley & UCSF Graduate Program in Bioengineering, UCSF Mission Bay Campus, San Francisco, CA 94158, USA
| | - Hariharasudhan D Chirra
- Department of Bioengineering and Therapeutic Sciences, University of California, San Francisco, CA 94158, USA
| | - Tejal A Desai
- Department of Bioengineering and Therapeutic Sciences, University of California, San Francisco, CA 94158, USA; UC Berkeley & UCSF Graduate Program in Bioengineering, UCSF Mission Bay Campus, San Francisco, CA 94158, USA.
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Chirra HD, Shao L, Ciaccio N, Fox CB, Wade JM, Ma A, Desai TA. Planar microdevices for enhanced in vivo retention and oral bioavailability of poorly permeable drugs. Adv Healthc Mater 2014; 3:1648-54. [PMID: 24711341 DOI: 10.1002/adhm.201300676] [Citation(s) in RCA: 42] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2013] [Revised: 03/07/2014] [Indexed: 11/09/2022]
Abstract
The development of novel oral drug delivery platforms for administering therapeutics in a safe and effective manner through the harsh gastrointestinal environment is of great importance. Here, the use of engineered thin planar poly(methyl methacrylate) (PMMA) microdevices is tested to enhance oral bioavailability of acyclovir, a poorly permeable drug. Acyclovir is loaded into the unidirectional drug releasing microdevice reservoirs using a drug entrapping photocross-linkable hydrogel matrix. An increase in acyclovir permeation across in vitro caco-2 monolayer is seen in the presence of microdevices as compared with acyclovir-entrapped hydrogels or free acyclovir solution. Cell proliferation studies show that microdevices are relatively nontoxic in nature for use in in vivo studies. Enhanced in vivo retention of microdevices is observed as their thin side walls experience minimal peristaltic shear stress as compared with spherical microparticles. Unidirectional acyclovir release and enhanced retention of microdevices achieve a 4.5-fold increase in bioavailability in vivo as compared with an oral gavage of acyclovir solution with the same drug mass. The enhanced oral bioavailability results suggest that thin, planar, bioadhesive, and unidirectional drug releasing microdevices will significantly improve the systemic and localized delivery of a broad range of oral therapeutics in the near future.
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Affiliation(s)
- Hariharasudhan D. Chirra
- Department of Bioengineering and Therapeutic Sciences; University of California; 1700 4th Street, Byers Hall 204, Box 2520 San Francisco CA 94158 USA
| | - Ling Shao
- Division of Gastroenterology, Department of Medicine; University of California; 513 Parnassus Ave San Francisco CA 94143 USA
| | - Natalie Ciaccio
- Department of Bioengineering and Therapeutic Sciences; University of California; 1700 4th Street, Byers Hall 204, Box 2520 San Francisco CA 94158 USA
| | - Cade B. Fox
- Department of Bioengineering and Therapeutic Sciences; University of California; 1700 4th Street, Byers Hall 204, Box 2520 San Francisco CA 94158 USA
| | - Jennifer M. Wade
- Department of Bioengineering and Therapeutic Sciences; University of California; 1700 4th Street, Byers Hall 204, Box 2520 San Francisco CA 94158 USA
| | - Averil Ma
- Division of Gastroenterology, Department of Medicine; University of California; 513 Parnassus Ave San Francisco CA 94143 USA
| | - Tejal A. Desai
- Department of Bioengineering and Therapeutic Sciences; University of California; 1700 4th Street, Byers Hall 204, Box 2520 San Francisco CA 94158 USA
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Abstract
There is no doubt that controlled and pulsatile drug delivery system is an important challenge in medicine over the conventional drug delivery system in case of therapeutic efficacy. However, the conventional drug delivery systems often offer a limited by their inability to drug delivery which consists of systemic toxicity, narrow therapeutic window, complex dosing schedule for long term treatment etc. Therefore, there has been a search for the drug delivery system that exhibit broad enhancing activity for more drugs with less complication. More recently, some elegant study has noted that, a new type of micro-electrochemical system or MEMS-based drug delivery systems called microchip has been improved to overcome the problems related to conventional drug delivery. Moreover, micro-fabrication technology has enabled to develop the implantable controlled released microchip devices with improved drug administration and patient compliance. In this article, we have presented an overview of the investigations on the feasibility and application of microchip as an advanced drug delivery system. Commercial manufacturing materials and methods, related other research works and current advancement of the microchips for controlled drug delivery have also been summarized.
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Affiliation(s)
| | - Chandra Datta Sumi
- b Department of Systems Biotechnology , Chung-Ang University , Anseong , Republic of Korea
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Santos A, Sinn Aw M, Bariana M, Kumeria T, Wang Y, Losic D. Drug-releasing implants: current progress, challenges and perspectives. J Mater Chem B 2014; 2:6157-6182. [DOI: 10.1039/c4tb00548a] [Citation(s) in RCA: 91] [Impact Index Per Article: 9.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
This review presents the different types and concepts of drug-releasing implants using new nanomaterials and nanotechnology-based devices.
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Affiliation(s)
- Abel Santos
- School of Chemical Engineering
- The University of Adelaide
- 5005 Adelaide, Australia
| | - Moom Sinn Aw
- School of Chemical Engineering
- The University of Adelaide
- 5005 Adelaide, Australia
| | - Manpreet Bariana
- School of Chemical Engineering
- The University of Adelaide
- 5005 Adelaide, Australia
- School of Dentistry
- The University of Adelaide
| | - Tushar Kumeria
- School of Chemical Engineering
- The University of Adelaide
- 5005 Adelaide, Australia
| | - Ye Wang
- School of Chemical Engineering
- The University of Adelaide
- 5005 Adelaide, Australia
| | - Dusan Losic
- School of Chemical Engineering
- The University of Adelaide
- 5005 Adelaide, Australia
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5-Fluorouracil delivery from a novel three-dimensional micro-device: in vitro and in vivo evaluation. Arch Pharm Res 2013; 36:1487-93. [DOI: 10.1007/s12272-013-0168-5] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2013] [Accepted: 05/27/2013] [Indexed: 12/12/2022]
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Abstract
Implantable drug-delivery systems provide new means for achieving therapeutic drug concentrations over entire treatment durations in order to optimize drug action. This article focuses on new drug administration modalities achieved using implantable drug-delivery systems that are enabled by micro- and nano-fabrication technologies, and microfluidics. Recent advances in drug administration technologies are discussed and remaining challenges are highlighted.
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Kulkarni SS, Kompella UB. Nanoparticles for Drug and Gene Delivery in Treating Diseases of the Eye. METHODS IN PHARMACOLOGY AND TOXICOLOGY 2013. [DOI: 10.1007/7653_2013_11] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
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Chirra HD, Desai TA. Multi-reservoir bioadhesive microdevices for independent rate-controlled delivery of multiple drugs. SMALL (WEINHEIM AN DER BERGSTRASSE, GERMANY) 2012; 8:3839-3846. [PMID: 22962019 PMCID: PMC3527694 DOI: 10.1002/smll.201201367] [Citation(s) in RCA: 40] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/19/2012] [Revised: 08/07/2012] [Indexed: 05/29/2023]
Abstract
A variety of oral administrative systems such as enterically coated tablets, capsules, particles, and liposomes have been developed to improve oral bioavailability of drugs. However, they suffer from poor intestinal localization and therapeutic efficacy due to the various physiological conditions and high shear fluid flow. Fabrication of novel microdevices combined with the introduction of controlled release, improved adhesion, selective targeting, and tissue permeation may overcome these issues and potentially diminish the toxicity and high frequency of conventional oral administration. Herein, thin, asymmetric, poly(methyl methacrylate) (PMMA) microdevices are fabricated with multiple reservoirs using photolithography and reactive ion etching. They are loaded with different individual model drug in each reservoir. Enhanced bioadhesion of the microdevices is observed in the presence of a conjugated of targeting protein (tomato lectin) to the PMMA surface. As compared to drug encompassing hydrogels, an increase in drug permeation across the caco-2 monolayer is noticed in the presence of a microdevice loaded with the same drug-hydrogel system. Also, the release of multiple drugs from their respective reservoirs is found to be independent from each other. The use of different hydrogel systems in each reservoir shows differences in the controlled release of the respective drugs over the same release period. These results suggest that, in the future, microfabricated unidirectional multi-drug releasing devices will have an impact on the oral administration of a broad range of therapeutics.
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Affiliation(s)
| | - Tejal A. Desai
- Corresponding Author. 1700 4 Street, Byers Hall 204, Box 2520, San Francisco, CA 94158, USA. Tel.: +1 415 514 4503; fax: +1 415 514 9656.
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Stevenson CL, Santini JT, Langer R. Reservoir-based drug delivery systems utilizing microtechnology. Adv Drug Deliv Rev 2012; 64:1590-602. [PMID: 22465783 DOI: 10.1016/j.addr.2012.02.005] [Citation(s) in RCA: 170] [Impact Index Per Article: 14.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2011] [Revised: 02/09/2012] [Accepted: 02/15/2012] [Indexed: 11/30/2022]
Abstract
This review covers reservoir-based drug delivery systems that incorporate microtechnology, with an emphasis on oral, dermal, and implantable systems. Key features of each technology are highlighted such as working principles, fabrication methods, dimensional constraints, and performance criteria. Reservoir-based systems include a subset of microfabricated drug delivery systems and provide unique advantages. Reservoirs, whether external to the body or implanted, provide a well-controlled environment for a drug formulation, allowing increased drug stability and prolonged delivery times. Reservoir systems have the flexibility to accommodate various delivery schemes, including zero order, pulsatile, and on demand dosing, as opposed to a standard sustained release profile. Furthermore, the development of reservoir-based systems for targeted delivery for difficult to treat applications (e.g., ocular) has resulted in potential platforms for patient therapy.
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Affiliation(s)
- Cynthia L Stevenson
- On Demand Therapeutics, Inc., One Industrial Way, Unit 1A, Tyngsboro, MA 01879, USA.
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Chirra HD, Desai TA. Emerging microtechnologies for the development of oral drug delivery devices. Adv Drug Deliv Rev 2012; 64:1569-78. [PMID: 22981755 PMCID: PMC3488155 DOI: 10.1016/j.addr.2012.08.013] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2011] [Revised: 08/06/2012] [Accepted: 08/12/2012] [Indexed: 10/27/2022]
Abstract
The development of oral drug delivery platforms for administering therapeutics in a safe and effective manner across the gastrointestinal epithelium is of much importance. A variety of delivery systems such as enterically coated tablets, capsules, particles, and liposomes have been developed to improve oral bioavailability of drugs. However, orally administered drugs suffer from poor localization and therapeutic efficacy due to various physiological conditions such as low pH, and high shear intestinal fluid flow. Novel platforms combining controlled release, improved adhesion, tissue penetration, and selective intestinal targeting may overcome these issues and potentially diminish the toxicity and high frequency of administration associated with conventional oral delivery. Microfabrication along with appropriate surface chemistry, provide a means to fabricate these platforms en masse with flexibility in tailoring the shape, size, reservoir volume, and surface characteristics of microdevices. Moreover, the same technology can be used to include integrated circuit technology and sensors for designing sophisticated autonomous drug delivery devices that promise to significantly improve point of care diagnostic and therapeutic medical applications. This review sheds light on some of the fabrication techniques and addresses a few of the microfabricated devices that can be effectively used for controlled oral drug delivery applications.
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Affiliation(s)
- Hariharasudhan D. Chirra
- Department of Bioengineering and Therapeutic Sciences, University of California, San Francisco, CA 94158, U.S.A
| | - Tejal A. Desai
- Department of Bioengineering and Therapeutic Sciences, University of California, San Francisco, CA 94158, U.S.A
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Affiliation(s)
- Eric E Nuxoll
- University of Minnesota Department of Pharmaceutics, 9-177 Weaver- Densford Hall, 308 Harvard St. SE, Minneapolis, MN 55455, USA
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Kim GY, Tyler BM, Tupper MM, Karp JM, Langer RS, Brem H, Cima MJ. Resorbable polymer microchips releasing BCNU inhibit tumor growth in the rat 9L flank model. J Control Release 2007; 123:172-8. [PMID: 17884232 PMCID: PMC5217465 DOI: 10.1016/j.jconrel.2007.08.003] [Citation(s) in RCA: 69] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2007] [Revised: 04/23/2007] [Accepted: 08/06/2007] [Indexed: 12/01/2022]
Abstract
Sustained local delivery of single agents and controlled delivery of multiple chemotherapeutic agents are sought for the treatment of brain cancer. A resorbable, multi-reservoir polymer microchip drug delivery system has been tested against a tumor model. The microchip reservoirs were loaded with 1,3-bis(2-chloroethyl)-1-nitrosourea (BCNU). BCNU was more stable at 37 degrees C within the microchip compared to a uniformly impregnated polymeric wafer (70% intact drug vs. 38%, at 48 h). The half-life of the intact free drug in the microchip was 11 days, which is a marked enhancement compared to its half-life in normal saline and 10% ethanol (7 and 10 min, respectively) [P. Tepe, S.J. Hassenbusch, R. Benoit, J.H. Anderson, BCNU stability as a function of ethanol concentration and temperature, J. Neurooncol. 10 (1991) 121-127; P. Kari, W.R. McConnell, J.M. Finkel, D.L. Hill, Distribution of Bratton-Marshall-positive material in mice following intravenous injections of nitrosoureas, Cancer Chemother. Pharmacol. 4 (1980) 243-248]. A syngeneic Fischer 344 9L gliosarcoma rat model was used to study the tumoricidal efficacy of BCNU delivery from the microchip or homogeneous polymer wafer. A dose-dependent decrease in tumor size was found for 0.17, 0.67, and 1.24 mg BCNU-microchips. Tumors treated with 1.24 mg BCNU-microchips showed significant tumor reduction (p=0.001) compared to empty control microchips at two weeks. The treatment showed similar efficacy to a polymer wafer with the same dosage. The microchip reservoir array may enable delivery of multiple drugs with independent release kinetics and formulations.
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Affiliation(s)
- Grace Y. Kim
- Division of Health Sciences and Technology, MIT/Harvard University, Cambridge, MA
| | - Betty M. Tyler
- Department of Neurosurgery, Johns Hopkins University, Cambridge, MA
| | | | | | | | - Henry Brem
- Department of Neurosurgery, Johns Hopkins University, Cambridge, MA
| | - Michael J. Cima
- Department of Materials Science and Engineering, MIT
- corresponding author, Michael J. Cima, , 617-253-6877 (phone), 617-258-6936 (fax)
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Feng CL, Embrechts A, Bredebusch I, Bouma A, Schnekenburger J, García-Parajó M, Domschke W, Vancso GJ, Schönherr H. Tailored interfaces for biosensors and cell-surface interaction studies via activation and derivatization of polystyrene-block-poly(tert-butyl acrylate) thin films. Eur Polym J 2007. [DOI: 10.1016/j.eurpolymj.2007.03.021] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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Staples M, Daniel K, Cima MJ, Langer R. Application of Micro- and Nano-Electromechanical Devices to Drug Delivery. Pharm Res 2006; 23:847-63. [PMID: 16715375 DOI: 10.1007/s11095-006-9906-4] [Citation(s) in RCA: 229] [Impact Index Per Article: 12.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2005] [Accepted: 12/27/2005] [Indexed: 11/28/2022]
Abstract
Micro- and nano-electromechanical systems (MEMS and NEMS)-based drug delivery devices have become commercially-feasible due to converging technologies and regulatory accommodation. The FDA Office of Combination Products coordinates review of innovative medical therapies that join elements from multiple established categories: drugs, devices, and biologics. Combination products constructed using MEMS or NEMS technology offer revolutionary opportunities to address unmet medical needs related to dosing. These products have the potential to completely control drug release, meeting requirements for on-demand pulsatile or adjustable continuous administration for extended periods. MEMS or NEMS technologies, materials science, data management, and biological science have all significantly developed in recent years, providing a multidisciplinary foundation for developing integrated therapeutic systems. If small-scale biosensor and drug reservoir units are combined and implanted, a wireless integrated system can regulate drug release, receive sensor feedback, and transmit updates. For example, an "artificial pancreas" implementation of an integrated therapeutic system would improve diabetes management. The tools of microfabrication technology, information science, and systems biology are being combined to design increasingly sophisticated drug delivery systems that promise to significantly improve medical care.
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Affiliation(s)
- Mark Staples
- MicroCHIPS, Inc., 6-B Preston Court, Bedford, Massachusetts 01730, USA.
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Polymers for tissue engineering, medical devices, and regenerative medicine. Concise general review of recent studies. POLYM ADVAN TECHNOL 2006. [DOI: 10.1002/pat.729] [Citation(s) in RCA: 291] [Impact Index Per Article: 16.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
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Grayson ACR, Cima MJ, Langer R. Size and temperature effects on poly(lactic-co-glycolic acid) degradation and microreservoir device performance. Biomaterials 2005; 26:2137-45. [PMID: 15576189 DOI: 10.1016/j.biomaterials.2004.06.033] [Citation(s) in RCA: 76] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2004] [Accepted: 06/14/2004] [Indexed: 10/26/2022]
Abstract
The component materials of controlled-release drug delivery systems are often selected based on their degradation rates. The release time of a drug from a system will strongly depend on the degradation rates of the component polymers. We have observed that some poly(lactic-co-glycolic acid) polymers (PLGA) exhibit degradation rates that depend on the size of the polymer object and the temperature of the surrounding environment. In vitro degradation studies of four different PLGA polymers showed that 150 microm thick membranes degraded more rapidly than 50 microm thick membranes, as characterized by gel permeation chromatography and mass loss measurements. Faster degradation was observed at 37 degrees C than 25 degrees C, and when the saline media was not refreshed. A biodegradable polymeric microreservoir device that we have developed relies on the degradation of polymeric membranes to deliver pulses of molecules from reservoirs on the device. Earlier molecular release was seen from devices having thicker PLGA membranes. Comparison of an in vitro release study from these devices with the degradation study suggests that reservoir membranes rupture and drug release occurs when a membrane threshold molecular weight of 5000-15000 is reached.
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Affiliation(s)
- Amy C Richards Grayson
- Department of Materials Science and Engineering, Massachusetts Institute of Technology, 77 Massachusetts Avenue, 12-011, Cambridge, MA 02139, USA.
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