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McDonald SM, Augustine EK, Lanners Q, Rudin C, Catherine Brinson L, Becker ML. Applied machine learning as a driver for polymeric biomaterials design. Nat Commun 2023; 14:4838. [PMID: 37563117 PMCID: PMC10415291 DOI: 10.1038/s41467-023-40459-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2023] [Accepted: 07/24/2023] [Indexed: 08/12/2023] Open
Abstract
Polymers are ubiquitous to almost every aspect of modern society and their use in medical products is similarly pervasive. Despite this, the diversity in commercial polymers used in medicine is stunningly low. Considerable time and resources have been extended over the years towards the development of new polymeric biomaterials which address unmet needs left by the current generation of medical-grade polymers. Machine learning (ML) presents an unprecedented opportunity in this field to bypass the need for trial-and-error synthesis, thus reducing the time and resources invested into new discoveries critical for advancing medical treatments. Current efforts pioneering applied ML in polymer design have employed combinatorial and high throughput experimental design to address data availability concerns. However, the lack of available and standardized characterization of parameters relevant to medicine, including degradation time and biocompatibility, represents a nearly insurmountable obstacle to ML-aided design of biomaterials. Herein, we identify a gap at the intersection of applied ML and biomedical polymer design, highlight current works at this junction more broadly and provide an outlook on challenges and future directions.
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Affiliation(s)
| | - Emily K Augustine
- Thomas Lord Department of Mechanical Engineering and Materials Science, Duke University, Durham, NC, USA
| | - Quinn Lanners
- Department of Biostatistics and Bioinformatics, Duke University, Durham, NC, USA
| | - Cynthia Rudin
- Department of Biostatistics and Bioinformatics, Duke University, Durham, NC, USA
| | - L Catherine Brinson
- Thomas Lord Department of Mechanical Engineering and Materials Science, Duke University, Durham, NC, USA
| | - Matthew L Becker
- Department of Chemistry, Duke University, Durham, NC, USA.
- Thomas Lord Department of Mechanical Engineering and Materials Science, Duke University, Durham, NC, USA.
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2
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Costello MA, Liu J, Chen B, Wang Y, Qin B, Xu X, Li Q, Lynd NA, Zhang F. Drug release mechanisms of high-drug-load, melt-extruded dexamethasone intravitreal implants. Eur J Pharm Biopharm 2023; 187:46-56. [PMID: 37037387 DOI: 10.1016/j.ejpb.2023.04.003] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2023] [Revised: 03/27/2023] [Accepted: 04/04/2023] [Indexed: 04/12/2023]
Abstract
Ozurdex is an FDA-approved sustained-release, biodegradable implant formulated to deliver the corticosteroid dexamethasone to the posterior segment of the eye for up to 6 months. Hot-melt extrusion is used to prepare the 0.46 mm × 6 mm, rod-shaped implant by embedding the drug in a matrix of poly(lactic-co-glycolic acid) (PLGA) in a 60:40 drug:polymer ratio by weight. In our previous work, the Ozurdex implant was carefully studied and reverse engineered to produce a compositionally and structurally equivalent implant for further analysis. In this work, the reverse-engineered implant is thoroughly characterized throughout the in vitro dissolution process to elucidate the mechanisms of controlled drug release. The implant exhibits a triphasic release profile in 37 °C normal saline with a small burst release (1-2 %), a one-week lag phase with limited release (less than10 %), and a final phase where the remainder of the dose is released over 3-4 weeks. The limited intermolecular interaction between dexamethasone and PLGA renders the breakdown of the polymer the dominating mechanism of controlled release. A close relationship between drug release and total implant mass loss was observed. Unique chemical and structural differences were seen between the core of the implant and the implant surface driven by diffusional limitations, autocatalytic hydrolysis, and osmotic effects.
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Affiliation(s)
- Mark A Costello
- University of Texas at Austin, College of Pharmacy, Department of Molecular Pharmaceutics and Drug Delivery, Austin, TX, USA
| | - Joseph Liu
- University of Texas at Austin, College of Pharmacy, Department of Molecular Pharmaceutics and Drug Delivery, Austin, TX, USA
| | - Beibei Chen
- University of Texas at Austin, College of Pharmacy, Department of Molecular Pharmaceutics and Drug Delivery, Austin, TX, USA
| | - Yan Wang
- U.S. Food and Drug Administration, Center for Drug Evaluation and Research, Office of Generic Drugs, Office of Research and Standards, Silver Spring, MD, USA
| | - Bin Qin
- U.S. Food and Drug Administration, Center for Drug Evaluation and Research, Office of Generic Drugs, Office of Research and Standards, Silver Spring, MD, USA
| | - Xiaoming Xu
- U.S. Food and Drug Administration, Center for Drug Evaluation and Research, Office of Pharmaceutical Quality, Office of Testing and Research, Silver Spring, MD, USA
| | - Qi Li
- U.S. Food and Drug Administration, Center for Drug Evaluation and Research, Office of Generic Drugs, Office of Research and Standards, Silver Spring, MD, USA
| | - Nathaniel A Lynd
- University of Texas at Austin, McKetta Department of Chemical Engineering and Texas Materials Institute, Austin, TX, USA
| | - Feng Zhang
- University of Texas at Austin, College of Pharmacy, Department of Molecular Pharmaceutics and Drug Delivery, Austin, TX, USA.
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3
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Costello MA, Liu J, Wang Y, Qin B, Xu X, Li Q, Lynd NA, Zhang F. Reverse engineering the Ozurdex dexamethasone intravitreal implant. Int J Pharm 2023; 634:122625. [PMID: 36690129 DOI: 10.1016/j.ijpharm.2023.122625] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2022] [Revised: 01/09/2023] [Accepted: 01/16/2023] [Indexed: 01/21/2023]
Abstract
Ozurdex is a biodegradable implant formulated for sustained-release delivery of the corticosteroid dexamethasone to the posterior segment of the eye. The small, rod-shaped implant is administered directly to the vitreous using a dedicated applicator, and releases drug for up to 6 months after administration. Sustained release is achieved by embedding dexamethasone in a matrix of 50:50 poly(lactic-co-glycolic acid) (PLGA). In this work, the Ozurdex implant was thoroughly characterized to enable the reverse engineering of a compositionally and structurally equivalent implant. Advanced imaging techniques such as scanning electron microscopy (SEM) and microcomputed tomography (microCT) revealed that the Ozurdex implant exhibits an irregular surface and an internal porosity of 6% due to a large number of discrete voids approximately 3 μm in diameter. Thermal and spectroscopic analyses showed limited interaction between the drug and the polymer, resulting in a two-phase system of dexamethasone crystals embedded within a PLGA matrix. Reverse-engineered implants with properties similar to Ozurdex were prepared using a two-step hot-melt extrusion process. The reverse-engineered implants exhibited a triphasic drug release profile similar to Ozurdex. This work seeks to provide insight into the manufacturing process and characterization of PLGA-based solid implants to support future generic product development.
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Affiliation(s)
- Mark A Costello
- University of Texas at Austin, College of Pharmacy, Department of Molecular Pharmaceutics and Drug Delivery, Austin, TX, USA
| | - Joseph Liu
- University of Texas at Austin, College of Pharmacy, Department of Molecular Pharmaceutics and Drug Delivery, Austin, TX, USA
| | - Yan Wang
- U.S. Food and Drug Administration, Center for Drug Evaluation and Research, Office of Generic Drugs, Office of Research and Standards, Silver Spring, MD, USA
| | - Bin Qin
- U.S. Food and Drug Administration, Center for Drug Evaluation and Research, Office of Generic Drugs, Office of Research and Standards, Silver Spring, MD, USA
| | - Xiaoming Xu
- U.S. Food and Drug Administration, Center for Drug Evaluation and Research, Office of Pharmaceutical Quality, Office of Testing and Research, Silver Spring, MD, USA
| | - Qi Li
- U.S. Food and Drug Administration, Center for Drug Evaluation and Research, Office of Generic Drugs, Office of Research and Standards, Silver Spring, MD, USA
| | - Nathaniel A Lynd
- University of Texas at Austin, McKetta Department of Chemical Engineering and Texas Materials Institute, Austin, TX, USA
| | - Feng Zhang
- University of Texas at Austin, College of Pharmacy, Department of Molecular Pharmaceutics and Drug Delivery, Austin, TX, USA.
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4
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Jeong Y, Kumar R, Lee Y. Electrochemical and spectroscopic studies on carbon‐coated and iodine‐doped
LiFeBO
3
as a cathode material for lithium‐ion batteries. B KOREAN CHEM SOC 2022. [DOI: 10.1002/bkcs.12663] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Affiliation(s)
- Yujin Jeong
- Department of Chemistry University of Ulsan Ulsan Republic of Korea
| | - Rajeev Kumar
- Chemical Industry Research Institution University of Ulsan Ulsan Republic of Korea
| | - Youngil Lee
- Department of Chemistry University of Ulsan Ulsan Republic of Korea
- Chemical Industry Research Institution University of Ulsan Ulsan Republic of Korea
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5
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Schilling AL, Cannon E, Fullerton-Shirey SK, Lee SE, Wang EW, Little SR. A ready-to-use, thermoresponsive, and extended-release delivery system for the paranasal sinuses. Drug Deliv Transl Res 2022; 12:708-719. [PMID: 34558028 DOI: 10.1007/s13346-021-01069-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 09/16/2021] [Indexed: 10/20/2022]
Abstract
A drug delivery system for the paranasal sinuses consisting of a freeze-dried thermoresponsive hydrogel with degradable microspheres, called FD-TEMPS (Freeze Dried-Thermogel, Extended-release Microsphere-based delivery to the Paranasal Sinuses), was developed. Glass transition temperatures (Tg') of the maximally freeze concentrated solutions consisting of poly(N-isopropylacrylamide) (pNIPAAm) and polyethylene glycol (PEG) were determined by differential scanning calorimetry, which informed optimization of the thermogel formulation. By replacing low molecular weight (MW) PEG (200 Da) with a higher MW PEG (2000 Da), the resulting freeze-dried gel exhibited a brittle texture, porous structure, and low residual moisture (< 3% measured by thermal gravimetric analysis). When combined with poly(lactic-co-glycolic acid) microspheres (PLGA MSs) and freeze dried, the complete system (FD-TEMPS) exhibited enhanced shelf-stability. Specifically, the smooth, spherical morphology of the MSs and initial release kinetics were maintained following 6 weeks of storage under ambient conditions. Furthermore, FD-TEMPS remained in place after application to a simulated mucosal surface, suggesting that it could be more uniformly distributed along the sinonasal mucosa in vivo. Freeze drying enables this delivery system to be stored as a ready-to-use product for better ease of clinical translation without compromising the thermoresponsive or sustained release characteristics that would enable local delivery of therapeutics to the sinonasal mucosa.
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Affiliation(s)
- Andrea L Schilling
- Department of Chemical Engineering, University of Pittsburgh, 940 Benedum Hall, 3700 O'Hara Street, Pittsburgh, PA, 15213, USA
| | - Erin Cannon
- Department of Chemical Engineering, University of Pittsburgh, 940 Benedum Hall, 3700 O'Hara Street, Pittsburgh, PA, 15213, USA
| | - Susan K Fullerton-Shirey
- Department of Chemical Engineering, University of Pittsburgh, 940 Benedum Hall, 3700 O'Hara Street, Pittsburgh, PA, 15213, USA
- Department of Electrical and Computer Engineering, University of Pittsburgh, 1238 Benedum Hall, 3700 O'Hara Street, Pittsburgh, PA, 15213, USA
| | - Stella E Lee
- Department of Otolaryngology-Head and Neck Surgery, University of Pittsburgh Medical Center, 1400 Locust Street, Suite 2100, Pittsburgh, PA, 15219, USA
| | - Eric W Wang
- Department of Otolaryngology-Head and Neck Surgery, University of Pittsburgh Medical Center, 1400 Locust Street, Suite 2100, Pittsburgh, PA, 15219, USA
| | - Steven R Little
- Department of Chemical Engineering, University of Pittsburgh, 940 Benedum Hall, 3700 O'Hara Street, Pittsburgh, PA, 15213, USA.
- Department of Bioengineering, University of Pittsburgh, 302 Benedum Hall, 3700 O'Hara Street, Pittsburgh, PA, 15213, USA.
- Department of Clinical and Translational Science, University of Pittsburgh, Forbes Tower, Suite 7057, Pittsburgh, PA, 15213, USA.
- McGowan Institute for Regenerative Medicine, University of Pittsburgh, 450 Technology Drive, Suite 300, Pittsburgh, PA, 15219, USA.
- Department of Immunology, University of Pittsburgh, 200 Lothrop Street, Pittsburgh, PA, 15213, USA.
- Department of Pharmaceutical Science, University of Pittsburgh, 3501 Terrace Street, Pittsburgh, PA, 15213, USA.
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6
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Schilling AL, Cannon E, Lee SE, Wang EW, Little SR. Advances in controlled drug delivery to the sinonasal mucosa. Biomaterials 2022; 282:121430. [DOI: 10.1016/j.biomaterials.2022.121430] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2021] [Revised: 01/09/2022] [Accepted: 02/17/2022] [Indexed: 12/20/2022]
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7
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Schilling AL, Carcella AR, Moore J, Zahid M, Lo C, Wang EW, Lee SE, Little SR. Compatibility of a Thermoresponsive and Controlled Release System for Promoting Sinonasal Cilia Regeneration. Macromol Biosci 2021; 21:e2100277. [PMID: 34390164 DOI: 10.1002/mabi.202100277] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2021] [Revised: 08/02/2021] [Indexed: 11/11/2022]
Abstract
The current clinical goal for managing chronic rhinosinusitis (CRS), a heterogenous disease of the paranasal sinuses, is to control inflammation, yet adjunct therapies that promote mucosal regeneration can improve the long-term health of the upper airways. The small natural openings to the sinuses, however, limit the efficacy of traditional drug delivery methods (i.e., nasal sprays and irrigation). Accordingly, a conformable thermoresponsive and controlled release system ("TEMPS", Thermogel, Extended-release Microsphere-based delivery to the Paranasal Sinuses) is developed. The poly(lactic-co-glycolic acid) microsphere component enables the encapsulation of numerous therapeutics, such as retinoic acid (RA), an analog of vitamin A (VA). Studies in CRS patients and preclinical models have shown that aqueous RA or VA gels promoted the differentiation of ciliated cells and improved mucosal healing following repeat applications. In the present study, TEMPS is designed for the controlled release of RA such that a single dose of RA-TEMPS delivers bioactive drug for at least 30 days. Furthermore, as TEMPS will be in direct contact with sinonasal tissue, its compatibility with ciliated human nasal epithelium is explored. After ex vivo incubation in thermogel for 24 h, cilia motility is maintained, providing evidence that TEMPS can be compatible for application along the sinonasal epithelium.
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Affiliation(s)
- Andrea L Schilling
- Department of Chemical Engineering, University of Pittsburgh, 940 Benedum Hall, 3700 O'Hara Street, Pittsburgh, PA, 15213, USA
| | - Adam R Carcella
- Department of Chemical Engineering, University of Pittsburgh, 940 Benedum Hall, 3700 O'Hara Street, Pittsburgh, PA, 15213, USA
| | - John Moore
- Department of Otolaryngology - Head and Neck Surgery, University of Pittsburgh Medical, Center, 1400 Locust Street, Suite 2100, Pittsburgh, PA, 15219, USA
| | - Maliha Zahid
- Department of Developmental Biology, University of Pittsburgh School of Medicine, 8112, Rangos Research Center, 530 45th Street, Pittsburgh, PA, 15201, USA
| | - Cecilia Lo
- Department of Developmental Biology, University of Pittsburgh School of Medicine, 8112, Rangos Research Center, 530 45th Street, Pittsburgh, PA, 15201, USA
| | - Eric W Wang
- Department of Otolaryngology - Head and Neck Surgery, University of Pittsburgh Medical, Center, 1400 Locust Street, Suite 2100, Pittsburgh, PA, 15219, USA
| | - Stella E Lee
- Department of Otolaryngology - Head and Neck Surgery, University of Pittsburgh Medical, Center, 1400 Locust Street, Suite 2100, Pittsburgh, PA, 15219, USA
| | - Steven R Little
- Department of Chemical Engineering, University of Pittsburgh, 940 Benedum Hall, 3700 O'Hara Street, Pittsburgh, PA, 15213, USA.,Department of Bioengineering, University of Pittsburgh, 302 Benedum Hall, 3700 O'Hara Street, Pittsburgh, PA, 15213, USA.,Department of Clinical and Translational Science, University of Pittsburgh, Forbes Tower, Suite 7057, Pittsburgh, PA, 15213, USA.,McGowan Institute for Regenerative Medicine, University of Pittsburgh, 450 Technology Drive, Suite 300, Pittsburgh, PA, 15219, USA.,Department of Immunology, University of Pittsburgh, 200 Lothrop Street, Pittsburgh, PA, 15213, USA.,Department of Pharmaceutical Science, University of Pittsburgh, 3501 Terrace Street, Pittsburgh, PA, 15213, USA
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Lotfalian S, Nematollahzadeh A, Ghasemi S. Hierarchically structured protein-based hollow-nanospheres for drug delivery. REACT FUNCT POLYM 2021. [DOI: 10.1016/j.reactfunctpolym.2021.104821] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
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9
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Park K, Otte A, Sharifi F, Garner J, Skidmore S, Park H, Jhon YK, Qin B, Wang Y. Potential Roles of the Glass Transition Temperature of PLGA Microparticles in Drug Release Kinetics. Mol Pharm 2020; 18:18-32. [PMID: 33331774 DOI: 10.1021/acs.molpharmaceut.0c01089] [Citation(s) in RCA: 37] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
Poly(lactic-co-glycolic acid) (PLGA) has been used for long-acting injectable drug delivery systems for more than 30 years. The factors affecting the properties of PLGA formulations are still not clearly understood. The drug release kinetics of PLGA microparticles are influenced by many parameters associated with the formulation composition, manufacturing process, and post-treatments. Since the drug release kinetics have not been explainable using the measurable properties, formulating PLGA microparticles with desired drug release kinetics has been extremely difficult. Of the various properties, the glass transition temperature, Tg, of PLGA formulations is able to explain various aspects of drug release kinetics. This allows examination of parameters that affect the Tg of PLGA formulations, and thus, affecting the drug release kinetics. The impacts of the terminal sterilization on the Tg and drug release kinetics were also examined. The analysis of drug release kinetics in relation to the Tg of PLGA formulations provides a basis for further understanding of the factors controlling drug release.
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Affiliation(s)
- Kinam Park
- Weldon School of Biomedical Engineering, Purdue University, West Lafayette, Indiana 47907, United States.,College of Pharmacy, Purdue University, West Lafayette, Indiana 47907, United States.,Akina, Inc., West Lafayette, Indiana 47906, United States
| | - Andrew Otte
- Weldon School of Biomedical Engineering, Purdue University, West Lafayette, Indiana 47907, United States
| | - Farrokh Sharifi
- Weldon School of Biomedical Engineering, Purdue University, West Lafayette, Indiana 47907, United States
| | - John Garner
- Akina, Inc., West Lafayette, Indiana 47906, United States
| | - Sarah Skidmore
- Akina, Inc., West Lafayette, Indiana 47906, United States
| | - Haesun Park
- Akina, Inc., West Lafayette, Indiana 47906, United States
| | - Young Kuk Jhon
- Office of Pharmaceutical Quality, Food and Drug Administration, Center for Drug Evaluation and Research, Silver Spring, Maryland 20993, United States
| | - Bin Qin
- Office of Generic Drugs, Food and Drug Administration, Center for Drug Evaluation and Research, Silver Spring, Maryland 20993, United States
| | - Yan Wang
- Office of Generic Drugs, Food and Drug Administration, Center for Drug Evaluation and Research, Silver Spring, Maryland 20993, United States
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10
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Schilling AL, Kulahci Y, Moore J, Wang EW, Lee SE, Little SR. A thermoresponsive hydrogel system for long-acting corticosteroid delivery into the paranasal sinuses. J Control Release 2020; 330:889-897. [PMID: 33157189 DOI: 10.1016/j.jconrel.2020.10.062] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2020] [Revised: 10/26/2020] [Accepted: 10/29/2020] [Indexed: 12/16/2022]
Abstract
Delivering localized treatment to the paranasal sinuses for diseases such as chronic rhinosinusitis (CRS) is particularly challenging because of the small natural openings leading from the sinuses that can be further obstructed by presence of inflammation. As such, oral steroids, topical nasal sprays or irrigation, and surgery can be utilized to treat persistent sinonasal inflammation, but there exists a need for post-operative options for long-term steroid delivery to prevent disease recurrence. In the present study, a Thermogel, Extended-release Microsphere-based-delivery to the Paranasal Sinuses (TEMPS) is developed with the corticosteroid mometasone furoate. Specifically, the bioactive steroid is released for 4 weeks from poly(lactic-co-glycolic acid) (PLGA) microspheres embedded in a poly(N-isopropylacrylamide) (p-NIPAAm)-based hydrogel. The temperature-responsive system undergoes a reversible sol-gel transition at 34-35 °C such that it can be applied as a liquid at ambient temperature, conforming to the sinonasal epithelium as it gels. In a rabbit model of CRS, TEMPS was maintained in rabbit sinuses and effectively reduced sinonasal inflammation as characterized by micro-computed tomography and histopathology analysis. Ultimately, the combination of controlled release microspheres with a thermoresponsive hydrogel provides flexibility for encapsulating therapeutics in a reversible and conforming system for localized delivery to the sinuses.
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Affiliation(s)
- Andrea L Schilling
- Department of Chemical Engineering, University of Pittsburgh, 940 Benedum Hall, 3700 O'Hara Street, Pittsburgh, PA, 15213, United States of America
| | - Yalcin Kulahci
- Department of Chemical Engineering, University of Pittsburgh, 940 Benedum Hall, 3700 O'Hara Street, Pittsburgh, PA, 15213, United States of America
| | - John Moore
- Department of Otolaryngology-Head and Neck Surgery, University of Pittsburgh Medical Center, 1400 Locust Street, Suite 2100, Pittsburgh, PA 15219, United States of America
| | - Eric W Wang
- Department of Otolaryngology-Head and Neck Surgery, University of Pittsburgh Medical Center, 1400 Locust Street, Suite 2100, Pittsburgh, PA 15219, United States of America
| | - Stella E Lee
- Department of Otolaryngology-Head and Neck Surgery, University of Pittsburgh Medical Center, 1400 Locust Street, Suite 2100, Pittsburgh, PA 15219, United States of America
| | - Steven R Little
- Department of Chemical Engineering, University of Pittsburgh, 940 Benedum Hall, 3700 O'Hara Street, Pittsburgh, PA, 15213, United States of America; Department of Bioengineering, University of Pittsburgh, 302 Benedum Hall, 3700 O'Hara Street, Pittsburgh, PA 15213, United States of America; Department of Clinical and Translational Science, University of Pittsburgh, Forbes Tower, Suite 7057, Pittsburgh, PA 15213, United States of America; McGowan Institute for Regenerative Medicine, University of Pittsburgh, 450 Technology Drive, Suite 300, Pittsburgh, PA 15219, United States of America; Department of Immunology, University of Pittsburgh, 200 Lothrop Street, Pittsburgh, PA 15213, United States of America; Department of Pharmaceutical Science, University of Pittsburgh, 3501 Terrace Street, Pittsburgh, PA 15213, United States of America.
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11
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Bruk LA, Dunkelberger KE, Khampang P, Hong W, Sadagopan S, Alper CM, Fedorchak MV. Controlled release of ciprofloxacin and ceftriaxone from a single ototopical administration of antibiotic-loaded polymer microspheres and thermoresponsive gel. PLoS One 2020; 15:e0240535. [PMID: 33045028 PMCID: PMC7549778 DOI: 10.1371/journal.pone.0240535] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2020] [Accepted: 09/28/2020] [Indexed: 12/17/2022] Open
Abstract
Acute otitis media (AOM) is the main indication for pediatric antibiotic prescriptions, accounting for 25% of prescriptions. While the use of topical drops can minimize the administered dose of antibiotic and adverse systemic effects compared to oral antibiotics, their use has limitations, partially due to low patient compliance, high dosing frequency, and difficulty of administration. Lack of proper treatment can lead to development of chronic OM, which may require invasive interventions. Previous studies have shown that gel-based drug delivery to the ear is possible with intratympanic injection or chemical permeation enhancers (CPEs). However, many patients are reluctant to accept invasive treatments and CPEs have demonstrated toxicity to the tympanic membrane (TM). We developed a novel method of delivering therapeutics to the TM and middle ear using a topical, thermoresponsive gel depot containing antibiotic-loaded poly(lactic-co-glycolic acid) microspheres. Our in vitro and ex vivo results suggest that the sustained presentation can safely allow therapeutically relevant drug concentrations to penetrate the TM to the middle ear for up to 14 days. Animal results indicate sufficient antibiotic released for treatment from topical administration 24h after bacterial inoculation. However, animals treated 72h after inoculation, a more clinically relevant treatment practice, displayed spontaneous clearance of infection as is also often observed in the clinic. Despite this variability in the disease model, data suggest the system can safely treat bacterial infection, with future studies necessary to optimize microsphere formulations for scaled up dosage of antibiotic as well as further investigation of the influence of spontaneous bacterial clearance and of biofilm formation on effectiveness of treatment. To our knowledge, this study represents the first truly topical drug delivery system to the middle ear without the use of CPEs.
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Affiliation(s)
- Liza A. Bruk
- Department of Bioengineering, University of Pittsburgh, Pittsburgh, PA, United States of America
| | | | - Pawjai Khampang
- Department of Otolaryngology and Communication Sciences, Medical College of Wisconsin, Milwaukee, WI, United States of America
| | - Wenzhou Hong
- Department of Otolaryngology and Communication Sciences, Medical College of Wisconsin, Milwaukee, WI, United States of America
| | - Srivatsun Sadagopan
- Department of Bioengineering, University of Pittsburgh, Pittsburgh, PA, United States of America
- Department of Neurobiology, University of Pittsburgh, Pittsburgh, PA, United States of America
| | - Cuneyt M. Alper
- Department of Otolaryngology, University of Pittsburgh, Pittsburgh, PA, United States of America
- Division of Pediatric Otolaryngology, UPMC Children’s Hospital of Pittsburgh, Pittsburgh, PA, United States of America
- Clinical and Translational Science Institute, University of Pittsburgh, Pittsburgh, PA, United States of America
| | - Morgan V. Fedorchak
- Department of Bioengineering, University of Pittsburgh, Pittsburgh, PA, United States of America
- Clinical and Translational Science Institute, University of Pittsburgh, Pittsburgh, PA, United States of America
- Department of Ophthalmology, University of Pittsburgh, Pittsburgh, PA, United States of America
- Department of Chemical Engineering, University of Pittsburgh, Pittsburgh, PA, United States of America
- * E-mail:
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12
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Snyder BL, Mohammed HS, Samways DSK, Shipp DA. Drug Delivery and Drug Efficacy from Amorphous Poly(thioether anhydrides). Macromol Biosci 2020; 20:e1900377. [PMID: 32207234 DOI: 10.1002/mabi.201900377] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2019] [Revised: 03/09/2020] [Accepted: 03/10/2020] [Indexed: 01/14/2023]
Abstract
The correlation between erosion and drug (lidocaine and 6-mercaptopurine, 6-MP) release from amorphous poly(thioether anhydrides), which are synthesized using radical-mediated thiol-ene polymerization, is reported. Cytotoxicity studies of the polymer toward human fibroblast human dermal fibroblasts adult, melanoma A-375, and breast cancer MCF-7 cells are conducted, and drug efficacy of a cancer and autoimmune disease drug (6-MP) when released from the poly(thioether anhydrides) is examined against two cancerous cell types (A-375 and MCF-7). Erosion and drug release studies reveal that lidocaine release is governed by network erosion whereas 6-MP is released by a combination of erosion and diffusion. The cytotoxicity studies show that all three cell types demonstrate high viability, thus cytocompatibility, to poly(thioether anhydrides). Toxicity to the material is dose dependent and comparable to other polyanhydride systems. The 6-MP cancer drug is shown to remain bioactive after encapsulation in the poly(thioether anhydride) matrix and the polymer does not appear to modify the efficacy of the drug.
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Affiliation(s)
- Brittany L Snyder
- Department of Chemistry and Biomolecular Science, Clarkson University, Potsdam, NY, 13699-5810, USA
| | - Halimatu S Mohammed
- Department of Chemistry and Biomolecular Science, Clarkson University, Potsdam, NY, 13699-5810, USA
| | - Damien S K Samways
- Department of Biology, Clarkson University, Potsdam, NY, 13699-5805, USA
| | - Devon A Shipp
- Department of Chemistry and Biomolecular Science, Clarkson University, Potsdam, NY, 13699-5810, USA.,Center for Advanced Materials Processing, Clarkson University, Potsdam, NY, 13699-5810, USA
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13
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Koshari SHS, Chang DP, Wang NB, Zarraga IE, Rajagopal K, Lenhoff AM, Wagner NJ. Data-Driven Development of Predictive Models for Sustained Drug Release. J Pharm Sci 2019; 108:3582-3591. [PMID: 31278916 DOI: 10.1016/j.xphs.2019.06.027] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2019] [Revised: 05/29/2019] [Accepted: 06/26/2019] [Indexed: 10/26/2022]
Abstract
Mathematical modeling of drug release can aid in the design and development of sustained delivery systems, but the parameter estimation of such models is challenging owing to the nonlinear mathematical structure and complexity and interdependency of the physical processes considered. Highly parameterized models often lead to overfitting, strong parameter correlations, and as a consequence, inaccurate model predictions for systems not explicitly part of the fitting database. Here, we show that an efficient stochastic optimization algorithm can be used not only to find robust estimates of global minima to such complex problems but also to generate metadata that allow quantitative evaluation of parameter sensitivity and correlation, which can be used for further model refinement and development. A practical methodology is described through the analysis of a predictive drug release model on published experimental data sets. The model is then used to design a zeroth-order release profile in an experimental system consisting of an antibody fragment in a poly(lactic-co-glycolic acid) solvent depot, which is validated experimentally. This approach allows rational decision-making when developing new models, selecting models for a specific application, or designing formulations for experimental trials.
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Affiliation(s)
- Stijn H S Koshari
- Center for Molecular and Engineering Thermodynamics, Department of Chemical and Biomolecular Engineering, University of Delaware, Newark, Delaware 19716
| | - Debby P Chang
- Drug Delivery Department, Genentech Inc., South San Francisco, California 94080
| | - Nathan B Wang
- Drug Delivery Department, Genentech Inc., South San Francisco, California 94080
| | - Isidro E Zarraga
- Biologics Drug Product Development, Sanofi Genzyme, 5 Mountain Road, Framingham MA 01701; Late Stage Pharmaceutical Development, Genentech Inc., South San Francisco, California 94080
| | - Karthikan Rajagopal
- Drug Delivery Department, Genentech Inc., South San Francisco, California 94080
| | - Abraham M Lenhoff
- Center for Molecular and Engineering Thermodynamics, Department of Chemical and Biomolecular Engineering, University of Delaware, Newark, Delaware 19716
| | - Norman J Wagner
- Center for Molecular and Engineering Thermodynamics, Department of Chemical and Biomolecular Engineering, University of Delaware, Newark, Delaware 19716.
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Local release of rapamycin by microparticles delays islet rejection within the anterior chamber of the eye. Sci Rep 2019; 9:3918. [PMID: 30850640 PMCID: PMC6408557 DOI: 10.1038/s41598-019-40404-0] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2018] [Accepted: 02/14/2019] [Indexed: 12/23/2022] Open
Abstract
The anterior chamber of the eye (ACE) has emerged as a promising clinical islet transplantation site because of its multiple advantages over the conventional intra-hepatic portal site. This includes reduced surgical invasiveness and increased islet graft survival rate. It also allows for enhanced accessibility and monitoring of the islets. Although the ACE is initially an immuno-privileged site, this privilege is disrupted once the islet grafts are re-vascularized. Given that the ACE is a confined space, achieving graft immune tolerance through local immunosuppressive drug delivery is therefore feasible. Here, we show that islet rejection in the ACE of mice can be significantly suppressed through local delivery of rapamycin by carefully designed sustained-release microparticles. In this 30-day study, allogeneic islet grafts with blank microparticles were completely rejected 18 days post-transplantation into mice. Importantly, allogeneic islet grafts co-injected with rapamycin releasing microparticles into a different eye of the same recipient were preserved much longer, with some grafts surviving for more than 30 days. Hence, islet allograft survival was enhanced by a localized and prolonged delivery of an immunosuppressive drug. We envisage that this procedure will relieve diabetic transplant recipients from harsh systemic immune suppression, while achieving improved glycemic control and reduced insulin dependence.
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15
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Cafferata EA, Alvarez C, Diaz KT, Maureira M, Monasterio G, González FE, Covarrubias C, Vernal R. Multifunctional nanocarriers for the treatment of periodontitis: Immunomodulatory, antimicrobial, and regenerative strategies. Oral Dis 2019; 25:1866-1878. [PMID: 30565778 DOI: 10.1111/odi.13023] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2018] [Revised: 10/31/2018] [Accepted: 12/11/2018] [Indexed: 12/12/2022]
Abstract
Periodontitis is an inflammatory disease, in which the host immuno-inflammatory response against the dysbiotic subgingival biofilm leads to the breakdown of periodontal tissues. Most of the available treatments seem to be effective in the short-term; nevertheless, permanent periodical controls and patient compliance compromise long-term success. Different strategies have been proposed for the modulation of the host immune response as potential therapeutic tools to take a better care of most susceptible periodontitis patients, such as drug local delivery approaches. Though, maintaining an effective drug concentration for a prolonged period of time has not been achieved yet. In this context, advanced drug delivery strategies using biodegradable nanocarriers have been proposed to avoid toxicity and frequency-related problems of treatment. The versatility of distinct nanocarriers allows the improvement of their loading and release capabilities and could be potentially used for microbiological control, periodontal regeneration, and/or immunomodulation. In the present review, we revise and discuss the most frequent biodegradable nanocarrier strategies proposed for the treatment of periodontitis, including polylactic-co-glycolic acid (PLGA), chitosan, and silica-derived nanoparticles, and further suggest novel therapeutic strategies.
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Affiliation(s)
- Emilio A Cafferata
- Periodontal Biology Laboratory, Department of Conservative Dentistry, Faculty of Dentistry, Universidad de Chile, Santiago, Chile.,Faculty of Dentistry, Universidad Peruana Cayetano Heredia, Lima, Perú
| | - Carla Alvarez
- Periodontal Biology Laboratory, Department of Conservative Dentistry, Faculty of Dentistry, Universidad de Chile, Santiago, Chile
| | - Karla T Diaz
- School of Public Health, Faculty of Medicine, Universidad de Chile, Santiago, Chile
| | - Miguel Maureira
- Laboratory of Nanobiomaterials, ICOD, Faculty of Dentistry, Universidad de Chile, Santiago, Chile
| | - Gustavo Monasterio
- Periodontal Biology Laboratory, Department of Conservative Dentistry, Faculty of Dentistry, Universidad de Chile, Santiago, Chile
| | - Fermín E González
- Laboratory of Experimental Immunology and Cancer, Department of Conservative Dentistry, Faculty of Dentistry, Universidad de Chile, Santiago, Chile
| | - Cristian Covarrubias
- Laboratory of Nanobiomaterials, ICOD, Faculty of Dentistry, Universidad de Chile, Santiago, Chile
| | - Rolando Vernal
- Periodontal Biology Laboratory, Department of Conservative Dentistry, Faculty of Dentistry, Universidad de Chile, Santiago, Chile.,Dentistry Unit, Faculty of Health Sciences, Universidad Autónoma de Chile, Santiago, Chile
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Monomer sequence in PLGA microparticles: Effects on acidic microclimates and in vivo inflammatory response. Acta Biomater 2018; 65:259-271. [PMID: 29101019 DOI: 10.1016/j.actbio.2017.10.043] [Citation(s) in RCA: 45] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2017] [Revised: 10/24/2017] [Accepted: 10/30/2017] [Indexed: 01/12/2023]
Abstract
Controlling the backbone architecture of poly(lactic-co-glycolic acid)s (PLGAs) is demonstrated to have a strong influence on the production and release of acidic degradation by-products in microparticle matrices. Previous efforts for controlling the internal and external accumulation of acidity for PLGA microparticles have focused on the addition of excipients including neutralization and anti-inflammatory agents. In this report, we utilize a sequence-control strategy to tailor the microstructure of PLGA. The internal acidic microclimate distributions within sequence-defined and random PLGA microparticles were monitored in vitro using a non-invasive ratiometric two-photon microscopy (TPM) methodology. Sequence-defined PLGAs were found to have minimal changes in pH distribution and lower amounts of percolating acidic by-products. A parallel scanning electron microscopy study further linked external morphological events to internal degradation-induced structural changes. The properties of the sequenced and random copolymers characterized in vitro translated to differences in in vivo behavior. The sequence alternating copolymer, poly LG, had lower granulomatous foreign-body reactions compared to random racemic PLGA with a 50:50 ratio of lactic to glycolic acid. STATEMENT OF SIGNIFICANCE This paper demonstrates that changing the monomer sequence in poly(lactic-co-glycolic acid)s (PLGAs) leads to dramatic differences in the rate of degradation and the internal acidic microclimate of microparticles degrading in vitro. We note that the acidic microclimates within these particles were imaged for the first time with two-photon microscopy, which gives an extremely clear and detailed picture of the degradation process. Importantly, we also document that the observed sequence-controlled in vitro processes translate into differences in the in vivo behavior of polymers which have the same L to G composition but differing microstructures. These data, placed in the context of our prior studies on swelling, erosion, and MW loss (Biomaterials2017, 117, 66 and other references cited within the manuscript), provide significant insight not only about sequence effects in PLGAs but into the underlying mechanisms of PLGA degradation in general.
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Ratay ML, Bellotti E, Gottardi R, Little SR. Modern Therapeutic Approaches for Noninfectious Ocular Diseases Involving Inflammation. Adv Healthc Mater 2017; 6:10.1002/adhm.201700733. [PMID: 29034584 PMCID: PMC5915344 DOI: 10.1002/adhm.201700733] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2017] [Revised: 07/25/2017] [Indexed: 12/12/2022]
Abstract
Dry eye disease, age-related macular degeneration, and uveitis are ocular diseases that significantly affect the quality of life of millions of people each year. In these diseases, the action of chemokines, proinflammatory cytokines, and immune cells drives a local inflammatory response that results in ocular tissue damage. Multiple therapeutic strategies are developed to either address the symptoms or abate the underlying cause of these diseases. Herein, the challenges to deliver drugs to the relevant location in the eye for each of these diseases are reviewed along with current and innovative therapeutic approaches that attempt to restore homeostasis within the ocular microenvironment.
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Affiliation(s)
- Michelle L. Ratay
- Department of Bioengineering, University of Pittsburgh, 427 Benedum Hall 3700 O’Hara Street Pittsburgh, Pa 15261
| | - Elena Bellotti
- Department of Chemical Engineering, University of Pittsburgh, 427 Benedum Hall 3700 O’Hara Street Pittsburgh, Pa 15261
| | - Riccardo Gottardi
- Department of Chemical Engineering, Department of Orthopedic Surgery, Ri.MED Foundation, 427 Benedum Hall 3700 O’Hara Street Pittsburgh, Pa 15261
| | - Steven R. Little
- Department of Chemical Engineering, Department of Bioengineering, Department of Ophthalmology, Department of Immunology, Department of Pharmaceutical Sciences, The McGowan Institute for Regenerative Medicine, 940 Benedum Hall 3700 O’Hara Street Pittsburgh Pa 15261
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Pareek A, Maheshwari S, Cherlo S, Thavva RSR, Runkana V. Modeling drug release through stimuli responsive polymer hydrogels. Int J Pharm 2017; 532:502-510. [DOI: 10.1016/j.ijpharm.2017.09.001] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2017] [Revised: 08/31/2017] [Accepted: 09/01/2017] [Indexed: 01/15/2023]
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19
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Rodrigues de Azevedo C, von Stosch M, Costa MS, Ramos A, Cardoso MM, Danhier F, Préat V, Oliveira R. Modeling of the burst release from PLGA micro- and nanoparticles as function of physicochemical parameters and formulation characteristics. Int J Pharm 2017; 532:229-240. [DOI: 10.1016/j.ijpharm.2017.08.118] [Citation(s) in RCA: 57] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2017] [Revised: 08/22/2017] [Accepted: 08/24/2017] [Indexed: 10/18/2022]
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20
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Fan YL, Hou HW, Tay HM, Guo WM, Berggren PO, Loo SCJ. Preservation of Anticancer and Immunosuppressive Properties of Rapamycin Achieved Through Controlled Releasing Particles. AAPS PharmSciTech 2017; 18:2648-2657. [PMID: 28251512 DOI: 10.1208/s12249-017-0745-x] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2016] [Accepted: 02/14/2017] [Indexed: 12/24/2022] Open
Abstract
Rapamycin is commonly used in chemotherapy and posttransplantation rejection suppression, where sustained release is preferred. Conventionally, rapamycin has to be administered in excess due to its poor solubility, and this often leads to cytotoxicity and undesirable side effects. In addition, rapamycin has been shown to be hydrolytically unstable, losing its bioactivity within a few hours. The use of drug delivery systems is hypothesized to preserve the bioactivity of rapamycin, while providing controlled release of this otherwise potent drug. This paper reports on the use of microparticles (MP) as a means to tune and sustain the delivery of bioactive rapamycin for up to 30 days. Rapamycin was encapsulated (100% efficiency) in poly(lactic-co-glycolic acid) (PLGA), polycaprolactone (PCL), or a mixture of both via an emulsion method. The use of different polymer types and mixture was shown to achieve a variety of release kinetics and profile. Released rapamycin was subsequently evaluated against breast cancer cell (MCF-7) and human lymphocyte cell (Jurkat). Inhibition of cell proliferation was in good agreement with in vitro release profiles, which confirmed the intact bioactivity of rapamycin. For Jurkat cells, the suppression of cell growth was proven to be effective up to 20 days, a duration significantly longer than free rapamycin. Taken together, these results demonstrate the ability to tune, sustain, and preserve the bioactivity of rapamycin using MP formulations. The sustained delivery of rapamycin could lead to better therapeutic effects than bolus dosage, at the same time improving patient compliance due to its long-acting duration.
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21
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Washington MA, Swiner DJ, Bell KR, Fedorchak MV, Little SR, Meyer TY. The impact of monomer sequence and stereochemistry on the swelling and erosion of biodegradable poly(lactic-co-glycolic acid) matrices. Biomaterials 2016; 117:66-76. [PMID: 27936418 DOI: 10.1016/j.biomaterials.2016.11.037] [Citation(s) in RCA: 62] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2016] [Revised: 11/12/2016] [Accepted: 11/24/2016] [Indexed: 01/01/2023]
Abstract
Monomer sequence is demonstrated to be a primary factor in determining the hydrolytic degradation profile of poly(lactic-co-glycolic acid)s (PLGAs). Although many approaches have been used to tune the degradation of PLGAs, little effort has been expended in exploring the sequence-control strategy exploited by nature in biopolymers. Cylindrical matrices and films prepared from a series of sequenced and random PLGAs were subjected to hydrolysis in a pH 7.4 buffer at 37 °C. Swelling ranged from 107% for the random racemic PLGA with a 50:50 ratio of lactic (L) to glycolic (G) units to 6% for the sequenced alternating copolymer poly LG. Erosion followed an inverse trend with the random 50:50 PLGA showing an erosion half-life of 3-4 weeks while poly LG required ca. >10 weeks. Stereosequence was found to play a large role in determining swelling and erosion; stereopure analogs swelled less and were slower to lose mass. Molecular weight loss followed similar trends and increases in dispersity correlated with the onset of significant swelling. The relative proportion of rapidly cleavable G-G linkages relative to G-L/L-G (moderate) and L-L (slow) correlates strongly with the degree of swelling observed and the rate of erosion. The dramatic sequence-dependent variation in swelling, in the absence of a parallel hydrophilicity trend, suggest that osmotic pressure, driven by the differential accumulation of degradation products, plays an important role.
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Affiliation(s)
| | - Devin J Swiner
- Department of Chemistry, University of Pittsburgh, Pittsburgh, PA 15260, USA
| | - Kerri R Bell
- Department of Chemistry, University of Pittsburgh, Pittsburgh, PA 15260, USA
| | - Morgan V Fedorchak
- Department of Chemical and Petroleum Engineering, University of Pittsburgh, Pittsburgh, PA 15260, USA; Department of Ophthalmology, University of Pittsburgh, Pittsburgh, PA 15260, USA; McGowan Institute for Regenerative Medicine, University of Pittsburgh, Pittsburgh, PA 15260, USA; Fox Center for Vision Restoration, University of Pittsburgh, Pittsburgh, PA 15260, USA
| | - Steven R Little
- Department of Chemical and Petroleum Engineering, University of Pittsburgh, Pittsburgh, PA 15260, USA; Department of Ophthalmology, University of Pittsburgh, Pittsburgh, PA 15260, USA; Department of Bioengineering, University of Pittsburgh, Pittsburgh, PA 15260, USA; Department of Immunology, University of Pittsburgh, Pittsburgh, PA 15260, USA; Department of Pharmaceutical Sciences, University of Pittsburgh, Pittsburgh, PA 15260, USA; McGowan Institute for Regenerative Medicine, University of Pittsburgh, Pittsburgh, PA 15260, USA
| | - Tara Y Meyer
- Department of Chemistry, University of Pittsburgh, Pittsburgh, PA 15260, USA; McGowan Institute for Regenerative Medicine, University of Pittsburgh, Pittsburgh, PA 15260, USA.
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22
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Roy A, Jhunjhunwala S, Bayer E, Fedorchak M, Little SR, Kumta PN. Porous calcium phosphate-poly (lactic-co-glycolic) acid composite bone cement: A viable tunable drug delivery system. MATERIALS SCIENCE & ENGINEERING. C, MATERIALS FOR BIOLOGICAL APPLICATIONS 2016; 59:92-101. [DOI: 10.1016/j.msec.2015.09.081] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/20/2015] [Accepted: 09/23/2015] [Indexed: 11/15/2022]
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23
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Rahmani S, Ross AM, Park TH, Durmaz H, Dishman AF, Prieskorn DM, Jones N, Altschuler RA, Lahann J. Dual Release Carriers for Cochlear Delivery. Adv Healthc Mater 2016; 5:94-100. [PMID: 26178272 PMCID: PMC5550902 DOI: 10.1002/adhm.201500141] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2015] [Revised: 05/03/2015] [Indexed: 12/18/2022]
Affiliation(s)
- Sahar Rahmani
- Biointerfaces Institute, University of Michigan, Ann Arbor, MI, 48109, USA
- Biomedical Engineering, University of Michigan, Ann Arbor, MI, 48109, USA
- Institute of Functional Interfaces (IFG), Karlsruhe Institute of Technology (KIT), 76344, Eggenstein-Leopoldshafen, Germany
| | - Astin M Ross
- Biomedical Engineering, University of Michigan, Ann Arbor, MI, 48109, USA
- Kresge Hearing Research Institute, University of Michigan, Ann Arbor, MI, 48109, USA
| | - Tae-Hong Park
- Chemical Engineering, University of Michigan, Ann Arbor, MI, 48109, USA
| | - Hakan Durmaz
- Biointerfaces Institute, University of Michigan, Ann Arbor, MI, 48109, USA
- Chemical Engineering, University of Michigan, Ann Arbor, MI, 48109, USA
| | - Acacia F Dishman
- Biointerfaces Institute, University of Michigan, Ann Arbor, MI, 48109, USA
- Biophysics, University of Michigan, Ann Arbor, MI, 48109, USA
| | - Diane M Prieskorn
- Kresge Hearing Research Institute, University of Michigan, Ann Arbor, MI, 48109, USA
| | - Nathan Jones
- Biointerfaces Institute, University of Michigan, Ann Arbor, MI, 48109, USA
| | - Richard A Altschuler
- Kresge Hearing Research Institute, University of Michigan, Ann Arbor, MI, 48109, USA
| | - Joerg Lahann
- Biointerfaces Institute, University of Michigan, Ann Arbor, MI, 48109, USA
- Biomedical Engineering, University of Michigan, Ann Arbor, MI, 48109, USA
- Institute of Functional Interfaces (IFG), Karlsruhe Institute of Technology (KIT), 76344, Eggenstein-Leopoldshafen, Germany
- Chemical Engineering, University of Michigan, Ann Arbor, MI, 48109, USA
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Bayer EA, Gottardi R, Fedorchak MV, Little SR. The scope and sequence of growth factor delivery for vascularized bone tissue regeneration. J Control Release 2015; 219:129-140. [PMID: 26264834 DOI: 10.1016/j.jconrel.2015.08.004] [Citation(s) in RCA: 56] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2015] [Revised: 08/01/2015] [Accepted: 08/03/2015] [Indexed: 12/21/2022]
Abstract
Bone regeneration is a complex process, that in vivo, requires the highly coordinated presentation of biochemical cues to promote the various stages of angiogenesis and osteogenesis. Taking inspiration from the natural healing process, a wide variety of growth factors are currently being released within next generation tissue engineered scaffolds (in a variety of ways) in order to heal non-union fractures and bone defects. This review will focus on the delivery of multiple growth factors to the bone regeneration niche, specifically 1) dual growth factor delivery signaling and crosstalk, 2) the importance of growth factor timing and temporal separation, and 3) the engineering of delivery systems that allow for temporal control over presentation of soluble growth factors. Alternative methods for growth factor presentation, including the use of gene therapy and platelet-rich plasma scaffolds, are also discussed.
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Affiliation(s)
- E A Bayer
- The University of Pittsburgh, Department of Bioengineering, USA; The University of Pittsburgh, The McGowan Institute for Regenerative Medicine, USA
| | - R Gottardi
- The University of Pittsburgh, Department of Chemical Engineering, USA; The University of Pittsburgh, Department of Orthopedic Surgery, USA; The University of Pittsburgh, The McGowan Institute for Regenerative Medicine, USA; RiMED Foundation, Palermo, Italy
| | - M V Fedorchak
- The University of Pittsburgh, Department of Bioengineering, USA; The University of Pittsburgh, Department of Chemical Engineering, USA; The University of Pittsburgh, Department of Ophthalmology, USA; The University of Pittsburgh, The McGowan Institute for Regenerative Medicine, USA
| | - S R Little
- The University of Pittsburgh, Department of Bioengineering, USA; The University of Pittsburgh, Department of Chemical Engineering, USA; The University of Pittsburgh, Department of Immunology, USA; The University of Pittsburgh, The McGowan Institute for Regenerative Medicine, USA.
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25
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Balmert SC, Zmolek AC, Glowacki AJ, Knab TD, Rothstein SN, Wokpetah JM, Fedorchak MV, Little SR. Positive Charge of "Sticky" Peptides and Proteins Impedes Release From Negatively Charged PLGA Matrices. J Mater Chem B 2015; 3:4723-4734. [PMID: 26085928 PMCID: PMC4465798 DOI: 10.1039/c5tb00515a] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
The influence of electrostatic interactions and/or acylation on release of charged ("sticky") agents from biodegradable polymer matrices was systematically characterized. We hypothesized that release of peptides with positive charge would be hindered from negatively charged poly(lactic-co-glycolic acid) (PLGA) microparticles. Thus, we investigated release of peptides with different degrees of positive charge from several PLGA microparticle formulations, with different molecular weights and/or end groups (acid- or ester-terminated). Indeed, release studies revealed distinct inverse correlations between the amount of positive charge on peptides and their release rates from each PLGA microparticle formulation. Furthermore, we examined the case of peptides with net charge that changes from negative to positive within the pH range observed in degrading microparticles. These charge changing peptides displayed counterintuitive release kinetics, initially releasing faster from slower degrading (less acidic) microparticles, and releasing slower from the faster degrading (more acidic) microparticles. Importantly, trends between agent charge and release rates for model peptides also translated to larger, therapeutically relevant proteins and oligonucleotides. The results of these studies may improve future design of controlled release systems for numerous therapeutic biomolecules exhibiting positive charge, ultimately reducing time-consuming and costly trial and error iterations of such formulations.
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Affiliation(s)
- Stephen C. Balmert
- Department of Bioengineering, University of Pittsburgh, PA, USA
- McGowan Institute for Regenerative Medicine, University of Pittsburgh, PA, USA
| | - Andrew C. Zmolek
- Department of Chemical Engineering, University of Pittsburgh, PA, USA
| | - Andrew J. Glowacki
- McGowan Institute for Regenerative Medicine, University of Pittsburgh, PA, USA
- Department of Chemical Engineering, University of Pittsburgh, PA, USA
| | - Timothy D. Knab
- McGowan Institute for Regenerative Medicine, University of Pittsburgh, PA, USA
- Department of Chemical Engineering, University of Pittsburgh, PA, USA
| | - Sam N. Rothstein
- McGowan Institute for Regenerative Medicine, University of Pittsburgh, PA, USA
- Department of Chemical Engineering, University of Pittsburgh, PA, USA
| | | | - Morgan V. Fedorchak
- McGowan Institute for Regenerative Medicine, University of Pittsburgh, PA, USA
- Department of Chemical Engineering, University of Pittsburgh, PA, USA
- Department of Ophthalmology, University of Pittsburgh, PA, USA
| | - Steven R. Little
- Department of Bioengineering, University of Pittsburgh, PA, USA
- McGowan Institute for Regenerative Medicine, University of Pittsburgh, PA, USA
- Department of Chemical Engineering, University of Pittsburgh, PA, USA
- Department of Immunology, University of Pittsburgh, PA, USA
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A systems approach to modeling drug release from polymer microspheres to accelerate in vitro to in vivo translation. J Control Release 2015; 211:74-84. [PMID: 26003043 DOI: 10.1016/j.jconrel.2015.04.045] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2014] [Revised: 02/28/2015] [Accepted: 04/11/2015] [Indexed: 11/23/2022]
Abstract
Mathematical models of controlled release that span the in vitro to in vivo transition are needed to speed the development and translation of clinically-relevant controlled release drug delivery systems. Fully mechanistic approaches are often challenged due to the use of highly-parameterized mathematically complex structures to capture the release mechanism. The simultaneous scarcity of in vivo data to inform these models and parameters leads to a situation where overfitting to capture observed phenomena is common. A data-driven approach to model development for controlled drug release from polymeric microspheres is taken herein, where physiological mechanisms impacting controlled release are incorporated to capture observed changes between in vitro release profiles and in vivo device dynamics. The model is generalizable, using non-specific binding to capture drug-polymer interactions via charge and molecular structure, and it has the ability to describe both inhibited (slowed) and accelerated release resulting from electrostatic or steric interactions. Reactive oxygen species (ROS)-induced degradation of biodegradable polymers was incorporated via a reaction-diffusion formalism, and this suggests that ROS may be the primary effector of the oft-observed accelerated in vivo release of polymeric drug delivery systems. Model performance is assessed through comparisons between model predictions and controlled release of several drugs from various-sized microparticles in vitro and in vivo.
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Volkov V, Vasconcelos A, Sárria MP, Gomes AC, Cavaco-Paulo A. Phosphorylation of silk fibroins improves the cytocompatibility of silk fibroin derived materials: A platform for the production of tuneable material. Biotechnol J 2014; 9:1267-78. [DOI: 10.1002/biot.201400302] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2014] [Revised: 06/09/2014] [Accepted: 07/31/2014] [Indexed: 01/16/2023]
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Wang A, Muhammad F, Qi W, Wang N, Chen L, Zhu G. Acid-induced release of curcumin from calcium containing nanotheranostic excipient. ACS APPLIED MATERIALS & INTERFACES 2014; 6:14377-14383. [PMID: 25025519 DOI: 10.1021/am503655z] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
Poor water solubility is believed one of the most critical problems of numerous promising pharmaceutical ingredients in their successful clinical utilization. Nanomedicine holds considerable promise to address this challenge, because it extends the therapeutic window of hydrophobic drugs through nanonization approach. Recently, the integration of diagnostic agents with smart therapeutic nanocarriers is also an emerging research arena to simultaneously visualize diseased tissues, achieve site specific drug release and track the impact of therapy. In this study, we have developed a biocompatible smart theranostic nanosystem which transports a highly promising hydrophobic drug (curcumin) in response to mildly acidic environment. As calcium is a main constituent of human body, hence we exploited the reversible calcium chelate formation tendency of divalent calcium to load and unload curcumin molecules. Moreover, an emerging T1 contrast agent is also tethered onto the surface of nanocarrier to realize MRI diagnosis application. In-vitro cell experiments revealed a significantly high chemotherapeutic efficiency of curcumin nanoformulation (IC50; 1.67 μg/mL), whereas free curcumin was found ineffective at the corresponding concentration (IC50; 29.72 μg/mL). MR imaging test also validated the performance of resulting system. Our strategy can be extended for the targeted delivery of other hydrophobic pharmaceutical ingredients.
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Affiliation(s)
- Aifei Wang
- State Key Laboratory of Inorganic Synthesis and Preparative Chemistry, College of Chemistry, and ‡College of Life Science, Jilin University , Changchun 130012, China
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Lewis JS, Roche C, Zhang Y, Brusko TM, Wasserfall CH, Atkinson M, Clare-Salzler MJ, Keselowsky BG. Combinatorial delivery of immunosuppressive factors to dendritic cells using dual-sized microspheres. J Mater Chem B 2014; 2:2562-2574. [PMID: 24778809 PMCID: PMC4000038 DOI: 10.1039/c3tb21460e] [Citation(s) in RCA: 51] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Microparticulate systems are beginning to show promise for delivery of modulatory agents for immunotherapeutic applications which modulate dendritic cell (DC) functions. Co-administration of multiple factors is an emerging theme in immune modulation which may prove beneficial in this setting. Herein, we demonstrate that localized, controlled delivery of multiple factors can be accomplished through poly (lactic-co-glycolic acid) (PLGA) microparticle systems fabricated in two size classes of phagocytosable and unphagocytosable microparticles (MPs). The immunosuppressive ability of combinatorial multi-factor dual MP systems was evaluated by investigating effects on DC maturation, DC resistance to LPS-mediated maturation and proliferation of allogeneic T cells in a mixed lymphocyte reaction. Phagocytosable MPs (~2 μm) were fabricated encapsulating either rapamycin (RAPA) or all-trans retinoic acid (RA), and unphagocytosable MPs (~30 μm) were fabricated encapsulating either transforming growth factor beta-1 (TGF-β1) or interleukin-10 (IL-10). Combinations of these MP classes reduced expression of stimulatory/costimulatory molecules (MHC-II, CD80 and CD86) in comparison to iDC and soluble controls, but not necessarily to single factor MPs. Dual MP-treated DCs resisted LPS-mediated activation, in a manner driven by the single factor phagocytosable MPs used. Dendritic cells treated with dual MP systems suppressed allogeneic T cell proliferation, generally demonstrating greater suppression by combination MPs than single factor formulations, particularly for the RA/IL-10 MPs. This work demonstrates feasibility of simultaneous targeted delivery of immunomodulatory factors to cell surface receptors and intracellular locations, and indicates that a combinatorial approach can boost immunoregulatory responses for therapeutic application in autoimmunity and transplantation.
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Affiliation(s)
- Jamal S. Lewis
- J. Crayton Pruitt Family Department of Biomedical Engineering, University of Florida, Gainesville, FL 32611
| | - Chris Roche
- J. Crayton Pruitt Family Department of Biomedical Engineering, University of Florida, Gainesville, FL 32611
| | - Ying Zhang
- J. Crayton Pruitt Family Department of Biomedical Engineering, University of Florida, Gainesville, FL 32611
| | - Todd M. Brusko
- Department of Pathology, Immunology and Laboratory Medicine, University of Florida, Gainesville, FL 32611
| | - Clive H. Wasserfall
- Department of Pathology, Immunology and Laboratory Medicine, University of Florida, Gainesville, FL 32611
| | - Mark Atkinson
- Department of Pathology, Immunology and Laboratory Medicine, University of Florida, Gainesville, FL 32611
| | - Michael J. Clare-Salzler
- Department of Pathology, Immunology and Laboratory Medicine, University of Florida, Gainesville, FL 32611
| | - Benjamin G. Keselowsky
- J. Crayton Pruitt Family Department of Biomedical Engineering, University of Florida, Gainesville, FL 32611
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Mealy J, Fedorchak M, Little S. In vitro characterization of a controlled-release ocular insert for delivery of brimonidine tartrate. Acta Biomater 2014; 10:87-93. [PMID: 24080317 DOI: 10.1016/j.actbio.2013.09.024] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2013] [Revised: 09/06/2013] [Accepted: 09/19/2013] [Indexed: 10/26/2022]
Abstract
Glaucoma is the second leading cause of blindness in the US. Brimonidine tartrate (BT) is a modern anti-glaucoma agent that is currently administered as frequently as a thrice-daily topical eye drop medication. Accordingly, compliance with BT regimens is low, limiting overall effectiveness. One attempt that has previously proved effective in addressing non-adherence is the formation of ocular inserts, such as the Ocusert(®), whose diffusion-based control released an older drug (pilocarpine) for a week-long period. Modern controlled drug-release technology provides an avenue for extending the release of practically any drug (including new drugs such as BT) for as long as 1 month from a singular insert. Currently, no controlled-release formulations for BT exist. This work outlines the development and characterization of a BT-releasing ocular insert designed from poly(lactic co-glycolic) acid/polyethylene glycol (PEG). It was found that a formulation containing 15% PEG can be created that produces a linear BT-release profile corresponding to BT eye drop delivery estimates. Additionally, these inserts were shown, through the use of atomic force microscopy and scanning electron microscopy, to have smooth surfaces and physical properties suitable for ophthalmic use.
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31
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Rothstein SN, Donahue C, Falo LD, Little SR. In silico programming of degradable microparticles to hide and then reveal immunogenic payloads in vivo. J Mater Chem B 2014; 2:6183-6187. [DOI: 10.1039/c4tb01042f] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
Abstract
Poly(lactic-co-glycolic) acid microparticles, mathematically designed for delayed release in vitro, hide and then reveal ovalbumin-alum in vivo without altering its immunogenicity.
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Affiliation(s)
| | - C. Donahue
- Departments of Dermatology
- Bioengineering
- McGowan Institute for Regenerative Medicine
- Clinical and Translational Science Institute
- University of Pittsburgh
| | - L. D. Falo
- Departments of Dermatology
- Bioengineering
- McGowan Institute for Regenerative Medicine
- Clinical and Translational Science Institute
- University of Pittsburgh
| | - S. R. Little
- Departments of Chemical and Petroleum Engineering
- Bioengineering
- Immunology
- McGowan Institute for Regenerative Medicine
- University of Pittsburgh
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32
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In vitro characterization of a sustained-release formulation for enfuvirtide. Antimicrob Agents Chemother 2013; 58:1797-9. [PMID: 24366751 DOI: 10.1128/aac.02440-13] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Although approved by the U.S. Food and Drug Administration, enfuvirtide is rarely used in combination antiretroviral therapies (cART) to treat HIV-1 infection, primarily because of its intense dosing schedule that requires twice-daily subcutaneous injection. Here, we describe the development of enfuvirtide-loaded, degradable poly(lactic-co-glycolic) acid microparticles that provide linear in vitro release of the drug over an 18-day period. This sustained-release formulation could make enfuvirtide more attractive for use in cART.
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33
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Prevention of inflammation-mediated bone loss in murine and canine periodontal disease via recruitment of regulatory lymphocytes. Proc Natl Acad Sci U S A 2013; 110:18525-30. [PMID: 24167272 DOI: 10.1073/pnas.1302829110] [Citation(s) in RCA: 145] [Impact Index Per Article: 13.2] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023] Open
Abstract
The hallmark of periodontal disease is the progressive destruction of gingival soft tissue and alveolar bone, which is initiated by inflammation in response to an invasive and persistent bacterial insult. In recent years, it has become apparent that this tissue destruction is associated with a decrease in local regulatory processes, including a decrease of forkhead box P3-expressing regulatory lymphocytes. Accordingly, we developed a controlled release system capable of generating a steady release of a known chemoattractant for regulatory lymphocytes, C-C motif chemokine ligand 22 (CCL22), composed of a degradable polymer with a proven track record of clinical translation, poly(lactic-co-glycolic) acid. We have previously shown that this sustained presentation of CCL22 from a point source effectively recruits regulatory T cells (Tregs) to the site of injection. Following administration of the Treg-recruiting formulation to the gingivae in murine experimental periodontitis, we observed increases in hallmark Treg-associated anti-inflammatory molecules, a decrease of proinflammatory cytokines, and a marked reduction in alveolar bone resorption. Furthermore, application of the Treg-recruiting formulation (fabricated with human CCL22) in ligature-induced periodontitis in beagle dogs leads to reduced clinical measures of inflammation and less alveolar bone loss under severe inflammatory conditions in the presence of a diverse periodontopathogen milieu.
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34
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Rahmani S, Park TH, Dishman AF, Lahann J. Multimodal delivery of irinotecan from microparticles with two distinct compartments. J Control Release 2013; 172:239-245. [PMID: 23973814 DOI: 10.1016/j.jconrel.2013.08.017] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2013] [Revised: 08/12/2013] [Accepted: 08/13/2013] [Indexed: 12/13/2022]
Abstract
In the last several decades, research in the field of drug delivery has been challenged with the fabrication of carrier systems engineered to deliver therapeutics to the target site with sustained and controlled release kinetics. Herein, we report the fabrication of microparticles composed of two distinct compartments: i) one compartment containing a pH responsive polymer, acetal-modified dextran, and PLGA (polylactide-co-glycolide), and ii) one compartment composed entirely of PLGA. We demonstrate the complete release of dextran from the microparticles during a 10-hour period in an acidic pH environment and the complete degradation of one compartment in less than 24h. This is in congruence with the stability of the same microparticles in neutral pH over the 24-hour period. Such microparticles can be used as pH responsive carrier systems for drug delivery applications where their cargo will only be released when the optimum pH window is reached. The feasibility of the microparticle system for such an application was confirmed by encapsulating a cancer therapeutic, irinotecan, in the compartment containing the acetal-modified dextran polymer and the pH dependent release over a 5-day period was studied. It was found that upon pH change to an acidic environment, over 50% of the drug was first released at a rapid rate for 10h, similar to that observed for the dextran release, before continuing at a more controlled rate for 4 days. As such, these microparticles can play an important role in the fabrication of novel drug delivery systems due to the selective, controlled, and pH responsive release of their encapsulated therapeutics.
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Affiliation(s)
- Sahar Rahmani
- Department of Biomedical Engineering, University of Michigan, Ann Arbor 48109, USA; Biointerfaces Institute, University of Michigan, Ann Arbor 48109, USA
| | - Tae-Hong Park
- Department of Chemical Engineering, University of Michigan, Ann Arbor 48109, USA
| | - Acacia Frances Dishman
- Department of Biophysics, University of Michigan, Ann Arbor 48109, USA; Biointerfaces Institute, University of Michigan, Ann Arbor 48109, USA
| | - Joerg Lahann
- Department of Biomedical Engineering, University of Michigan, Ann Arbor 48109, USA; Department of Chemical Engineering, University of Michigan, Ann Arbor 48109, USA; Biointerfaces Institute, University of Michigan, Ann Arbor 48109, USA.
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Gubskaya AV, Khan IJ, Valenzuela LM, Lisnyak YV, Kohn J. Investigating the Release of a Hydrophobic Peptide from Matrices of Biodegradable Polymers: An Integrated Method Approach. POLYMER 2013; 54:3806-3820. [PMID: 24039300 DOI: 10.1016/j.polymer.2013.05.038] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
The objectives of this work were: (1) to select suitable compositions of tyrosine-derived polycarbonates for controlled delivery of voclosporin, a potent drug candidate to treat ocular diseases, (2) to establish a structure-function relationship between key molecular characteristics of biodegradable polymer matrices and drug release kinetics, and (3) to identify factors contributing in the rate of drug release. For the first time, the experimental study of polymeric drug release was accompanied by a hierarchical sequence of three computational methods. First, suitable polymer compositions used in subsequent neural network modeling were determined by means of response surface methodology (RSM). Second, accurate artificial neural network (ANN) models were built to predict drug release profiles for fifteen polymers located outside the initial design space. Finally, thermodynamic properties and hydrogen-bonding patterns of model drug-polymer complexes were studied using molecular dynamics (MD) technique to elucidate a role of specific interactions in drug release mechanism. This research presents further development of methodological approaches to meet challenges in the design of polymeric drug delivery systems.
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Affiliation(s)
- Anna V Gubskaya
- New Jersey Center for Biomaterials, Rutgers, The State University of New Jersey, Piscataway, NJ 08854-8087, USA
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36
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Ford Versypt AN, Pack DW, Braatz RD. Mathematical modeling of drug delivery from autocatalytically degradable PLGA microspheres--a review. J Control Release 2012; 165:29-37. [PMID: 23103455 DOI: 10.1016/j.jconrel.2012.10.015] [Citation(s) in RCA: 221] [Impact Index Per Article: 18.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2012] [Accepted: 10/18/2012] [Indexed: 10/27/2022]
Abstract
PLGA microspheres are widely studied for controlled release drug delivery applications, and many models have been proposed to describe PLGA degradation and erosion and drug release from the bulk polymer. Autocatalysis is known to have a complex role in the dynamics of PLGA erosion and drug transport and can lead to size-dependent heterogeneities in otherwise uniformly bulk-eroding polymer microspheres. The aim of this review is to highlight mechanistic, mathematical models for drug release from PLGA microspheres that specifically address interactions between phenomena generally attributed to autocatalytic hydrolysis and mass transfer limitation effects. Predictions of drug release profiles by mechanistic models are useful for understanding mechanisms and designing drug release particles.
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Affiliation(s)
- Ashlee N Ford Versypt
- Department of Chemical and Biomolecular Engineering, University of Illinois at Urbana-Champaign, Urbana, IL 61801, USA
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37
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Rothstein SN, Kay JE, Schopfer FJ, Freeman BA, Little SR. A retrospective mathematical analysis of controlled release design and experimentation. Mol Pharm 2012; 9:3003-11. [PMID: 23009671 DOI: 10.1021/mp300388w] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
The development and performance evaluation of new biodegradable polymer controlled release formulations relies on successful interpretation and evaluation of in vitro release data. However, depending upon the extent of empirical characterization, release data may be open to more than one qualitative interpretation. In this work, a predictive model for release from degradable polymer matrices was applied to a number of published release data in order to extend the characterization of release behavior. Where possible, the model was also used to interpolate and extrapolate upon collected released data to clarify the overall duration of release and also kinetics of release between widely spaced data points. In each case examined, mathematical predictions of release coincide well with experimental results, offering a more definitive description of each formulation's performance than was previously available. This information may prove particularly helpful in the design of future studies, such as when calculating proper dosing levels or determining experimental end points in order to more comprehensively evaluate a controlled release system's performance.
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Affiliation(s)
- Sam N Rothstein
- Department of Chemical Engineering, University of Pittsburgh, Pittsburgh, Pennsylvania, United States
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38
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Jhunjhunwala S, Raimondi G, Glowacki AJ, Hall SJ, Maskarinec D, Thorne SH, Thomson AW, Little SR. Bioinspired controlled release of CCL22 recruits regulatory T cells in vivo. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2012; 24:4735-8. [PMID: 22821823 PMCID: PMC3491880 DOI: 10.1002/adma.201202513] [Citation(s) in RCA: 41] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/20/2012] [Indexed: 05/20/2023]
Affiliation(s)
- Siddharth Jhunjhunwala
- 360B CNBIO, 300 Technology Drive, Department of Bioengineering, University of Pittsburgh, Pittsburgh, PA-15219, USA
- 450 Technology Drive, Suite 300, McGowan Institute for Regenerative Medicine, University of Pittsburgh, Pittsburgh, PA-15219, USA
| | - Giorgio Raimondi
- 200 Lothrop Street, Department of Surgery, University of Pittsburgh, Pittsburgh, PA-15261, USA
- 200 Lothrop Street, W1540, Thomas E. Starzl Biomedical Science Tower, University of Pittsburgh, Pittsburgh, PA-15261, USA
| | - Andrew J. Glowacki
- 3700 O’Hara Street, #1249, Department of Chemical Engineering, University of Pittsburgh, Pittsburgh, PA-15261, USA
- 450 Technology Drive, Suite 300, McGowan Institute for Regenerative Medicine, University of Pittsburgh, Pittsburgh, PA-15219, USA
| | - Sherri J. Hall
- 360B CNBIO, 300 Technology Drive, Department of Bioengineering, University of Pittsburgh, Pittsburgh, PA-15219, USA
| | - Dan Maskarinec
- 360B CNBIO, 300 Technology Drive, Department of Bioengineering, University of Pittsburgh, Pittsburgh, PA-15219, USA
| | - Stephen H. Thorne
- 200 Lothrop Street, Department of Surgery, University of Pittsburgh, Pittsburgh, PA-15261, USA
- 200 Lothrop Street, E1040, Thomas E. Starzl Biomedical Science Tower, University of Pittsburgh, Pittsburgh, PA-15261, USA
| | - Angus W. Thomson
- 200 Lothrop Street, Department of Surgery, University of Pittsburgh, Pittsburgh, PA-15261, USA
- 200 Lothrop Street, E1040, Thomas E. Starzl Biomedical Science Tower, University of Pittsburgh, Pittsburgh, PA-15261, USA
- 200 Lothrop Street, W1540, Thomas E. Starzl Biomedical Science Tower, University of Pittsburgh, Pittsburgh, PA-15261, USA
| | - Steven R. Little
- 360B CNBIO, 300 Technology Drive, Department of Bioengineering, University of Pittsburgh, Pittsburgh, PA-15219, USA
- 3700 O’Hara Street, #1249, Department of Chemical Engineering, University of Pittsburgh, Pittsburgh, PA-15261, USA
- 200 Lothrop Street, E1040, Thomas E. Starzl Biomedical Science Tower, University of Pittsburgh, Pittsburgh, PA-15261, USA
- 450 Technology Drive, Suite 300, McGowan Institute for Regenerative Medicine, University of Pittsburgh, Pittsburgh, PA-15219, USA
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39
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Balmert SC, Little SR. Biomimetic delivery with micro- and nanoparticles. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2012; 24:3757-78. [PMID: 22528985 PMCID: PMC3627374 DOI: 10.1002/adma.201200224] [Citation(s) in RCA: 96] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/16/2012] [Indexed: 05/16/2023]
Abstract
The nascent field of biomimetic delivery with micro- and nanoparticles (MNP) has advanced considerably in recent years. Drawing inspiration from the ways that cells communicate in the body, several different modes of "delivery" (i.e., temporospatial presentation of biological signals) have been investigated in a number of therapeutic contexts. In particular, this review focuses on (1) controlled release formulations that deliver natural soluble factors with physiologically relevant temporal context, (2) presentation of surface-bound ligands to cells, with spatial organization of ligands ranging from isotropic to dynamically anisotropic, and (3) physical properties of particles, including size, shape and mechanical stiffness, which mimic those of natural cells. Importantly, the context provided by multimodal, or multifactor delivery represents a key element of most biomimetic MNP systems, a concept illustrated by an analogy to human interpersonal communication. Regulatory implications of increasingly sophisticated and "cell-like" biomimetic MNP systems are also discussed.
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Affiliation(s)
- Stephen C Balmert
- Department of Chemical Engineering, University of Pittsburgh, Pittsburgh, PA 15261 USA
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40
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Singh V, Singh S, Das S, Kumar A, Self WT, Seal S. A facile synthesis of PLGA encapsulated cerium oxide nanoparticles: release kinetics and biological activity. NANOSCALE 2012; 4:2597-2605. [PMID: 22419352 DOI: 10.1039/c2nr12131j] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
In the present article a facile synthesis of cerium oxide nanoparticles (CNPs) encapsulated in PLGA microparticles is reported. The release kinetics of the CNPs from the PLGA matrix was investigated under acidic, basic and near-neutral pH. A diffusion model was applied to determine the diffusivity of the CNPs from the PLGA matrix. The morphology of the degraded PLGA particles was characterized by high resolution SEM. Superoxide dismutase (SOD) mimetic activity was retained in released CNPs for a longer period of time (∼90 days) under different pH. PLGA encapsulated CNP showed excellent biocompatibility. This study demonstrates a potential strategy to deliver CNPs using biodegradable PLGA that ensures a slow release of the CNPs over a long period of time. Thus, the synthesized PLGA encapsulated CNPs could find potential applications in tissue engineering like bone remodelling and regeneration, and protection from disorders caused by neurodegeneration.
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Affiliation(s)
- Virendra Singh
- Mechanical Materials and Aerospace Engineering, Nanoscience and Technology Center, Advanced Materials Processing and Analysis Center, University of Central Florida, USA
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41
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Jhunjhunwala S, Little SR. Microparticulate systems for targeted drug delivery to phagocytes. Cell Cycle 2012; 10:2047-8. [PMID: 21623160 DOI: 10.4161/cc.10.13.15713] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
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42
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Khung YL, Li Lee W, Chui KL, Liu Y, Lim MP, Huang CL, Loo SCJ. Microencapsulation of dye- and drug-loaded particles for imaging and controlled release of multiple drugs. Adv Healthc Mater 2012. [PMID: 23184718 DOI: 10.1002/adhm.201100007] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
A polymeric microcapsule that can house different drug-loaded particles using a simple emulsion packaging technique is presented. Compared to the neat microparticles, microcapsules simultaneously release multiple drugs in a sustained manner. These microcapsules could provide a means of controlling release of multiple drugs.
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Affiliation(s)
- Yit-Lung Khung
- School of Materials Science and Engineering, Nanyang Technological University, 50 Nanyang Avenue, 639798, Singapore
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43
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Jhunjhunwala S, Balmert SC, Raimondi G, Dons E, Nichols EE, Thomson AW, Little SR. Controlled release formulations of IL-2, TGF-β1 and rapamycin for the induction of regulatory T cells. J Control Release 2012; 159:78-84. [PMID: 22285546 DOI: 10.1016/j.jconrel.2012.01.013] [Citation(s) in RCA: 76] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2011] [Revised: 01/04/2012] [Accepted: 01/13/2012] [Indexed: 12/27/2022]
Abstract
The absence of regulatory T cells (Treg) is a hallmark for a wide variety of disorders such as autoimmunity, dermatitis, periodontitis and even transplant rejection. A potential treatment option for these disorders is to increase local Treg numbers. Enhancing local numbers of Treg through in situ Treg expansion or induction could be a potential treatment option for these disorders. Current methods for in vivo Treg expansion rely on biologic therapies, which are not Treg-specific and are associated with many adverse side-effects. Synthetic formulations capable of inducing Treg could be an alternative strategy to achieve in situ increase in Treg numbers. Here we report the development and in vitro testing of a Treg-inducing synthetic formulation that consists of controlled release vehicles for IL-2, TGF-β and rapamycin (a combination of cytokines and drugs that have previously been reported to induce Treg). We demonstrate that IL-2, TGF-β and rapamycin (rapa) are released over 3-4weeks from these formulations. Additionally, Treg induced in the presence of these formulations expressed the canonical markers for Treg (phenotype) and suppressed naïve T cell proliferation (function) at levels similar to soluble factor induced Treg as well as naturally occurring Treg. Most importantly, we show that these release formulations are capable of inducing FoxP3(+) Treg in human cells in vitro. In conclusion, our data suggest that controlled release formulations of IL-2, TGF-β and rapa can induce functional Treg in vitro with the potential to be developed into an in vivo Treg induction and expansion therapy.
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Affiliation(s)
- Siddharth Jhunjhunwala
- Department of Bioengineering, University of Pittsburgh, Pittsburgh, PA 15261, United States
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44
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Nguyen EH, Schwartz MP, Murphy WL. Biomimetic approaches to control soluble concentration gradients in biomaterials. Macromol Biosci 2011; 11:483-92. [PMID: 21265021 PMCID: PMC3735129 DOI: 10.1002/mabi.201000448] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2010] [Revised: 12/29/2010] [Indexed: 01/20/2023]
Abstract
Soluble concentration gradients play a critical role in controlling tissue formation during embryonic development. The importance of soluble signaling in biology has motivated engineers to design systems that allow precise and quantitative manipulation of gradient formation in vitro. Engineering techniques have increasingly moved to the third dimension in order to provide more physiologically relevant models to study the biological role of gradient formation and to guide strategies for controlling new tissue formation for therapeutic applications. This review provides an overview of efforts to design biomimetic strategies for soluble gradient formation, with a focus on microfluidic techniques and biomaterials approaches for moving gradient generation to the third dimension.
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Affiliation(s)
- Eric H. Nguyen
- Department of Biomedical Engineering, Wisconsin Institutes for Medical Research, University of Wisconsin-Madison, 1111 Highland Avenue, Madison, Wisconsin 53705, USA
| | - Michael P. Schwartz
- Department of Biomedical Engineering, Wisconsin Institutes for Medical Research, University of Wisconsin-Madison, 1111 Highland Avenue, Madison, Wisconsin 53705, USA
| | - William L. Murphy
- Department of Biomedical Engineering, Wisconsin Institutes for Medical Research, University of Wisconsin-Madison, 1111 Highland Avenue, Madison, Wisconsin 53705, USA, Fax: (608) 265 9239. Department of Pharmacology, Wisconsin Institutes for Medical Research, University of Wisconsin-Madison, 1111 Highland Avenue, Madison, Wisconsin 53705, USA. Department of Orthopedics & Rehabilitation, Wisconsin Institutes for Medical Research, University of Wisconsin-Madison, 1111 Highland Avenue, Madison, Wisconsin 53705, USA
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