A polyanhydride implant (Septacin) containing gentamicin sulfate was developed for sustained local delivery of the drug to the site of infection in the treatment of osteomyelitis. Laboratory-scale injection molding equipment was utilized to fabricate the implant for in vitro characterization. Molding conditions were optimized to produce implants with a skin-core structure which was found to be critical in preventing the initial cracking of the implant during in vitro drug release test in water. A manufacturing process consisting of twin-screw extrusion, pelletizing, and injection molding was developed. Polymer-drug pellets were characterized with respect to copolymer molecular weight and drug content uniformity. The implants were terminally sterilized by gamma-radiation which was found to cause increase in copolymer molecular weight as a result of polymer chain extension. The stability of Septacin was evaluated as a function of storage temperature and time. A marked decline in copolymer molecular weight occurred in samples stored above freezing temperatures and significantly slower drug-release profiles were also exhibited by these samples. In vivo drug release from Septacin in rats showed that the gentamicin plasma levels were extremely low, indicating the low systemic exposure to gentamicin. Furthermore, Septacin samples have demonstrated efficacy in the rat skin-abscess and horse-joint infection models. Results from a human in vivo study also showed high local drug concentrations at implantation sites while systemic exposure to the drug was minimal.
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http://dx.doi.org/10.1016/s0169-409x(02)00053-4 | DOI Listing |
Angew Chem Int Ed Engl
January 2025
Chang Chun Institute of Applied Chemistry Chinese Academy of Sciences, Key Laboratory of Polymer Ecomaterials, 5625 Renmin Street, Changchun, , 130022, Changchun, CHINA.
Living cationic polymerization (LCP) is a classical technique for precision polymer synthesis; however, due to the high sensitivity of cationic active species towards chain-transfer/termination events, it is notoriously difficult to control polymerization under mild conditions, which inhibits its progress in advanced materials engineering. Here, we unlock a practical anion-binding catalytic strategy to address the historical dilemma in LCP. Our experimental and mechanistic studies demonstrate that commercially accessible hexafluoroisopropanol (HFIP), when used in high loading, can create higher-order HFIP aggregates to tame dormant-active species equilibrium via non-covalent anion-binding principle, in turn inducing distinctive polymerization kinetics behaviors that grant efficient chain propagation while minimizing competitive side reactions.
View Article and Find Full Text PDFAdv Mater
January 2025
School of Materials Science and Engineering, Chongqing University of Technology, Chongqing, 400054, China.
Polymeric room temperature phosphorescence (RTP) materials have been well developed and utilized in various fields. However, their fast thermo- and moisture-quenching behavior highly limit their applications in certain harsh environments. Therefore, the preparation of materials with thermo- and moisture-resistant phosphorescence is greatly attractive.
View Article and Find Full Text PDFJ Colloid Interface Sci
April 2025
Shanghai Key Laboratory of Molecular Catalysis and Innovative Materials, Collaborative Innovation Center of Chemistry for Energy Materials, Department of Chemistry, Fudan University, Shanghai, China. Electronic address:
Triblock Pluronics of polyoxyethylene (PEO) and polyoxypropylene (PPO) are identified as competent suppressors for copper (Cu) electroplating in advanced electronics manufacturing. However, the specific interfacial roles of PEO and PPO blocks in Pluronic suppressors, are not yet fully understood, which is crucial for the rational design of effective suppressors. Herein, the influences of composition and block arrangement of such Pluronics on the inhibition against Cu plating are systematically investigated.
View Article and Find Full Text PDFPharmaceutics
December 2024
Department of Polymer Science and Engineering, Pusan National University, Busan 46241, Republic of Korea.
The use of polymeric nanoparticles (NPs) in drug delivery systems offers the advantages of enhancing drug efficacy and minimizing side effects; In this study, L-threonine polyurethane (LTPU) NPs have been fabricated by water-in-oil-in-water emulsion and solvent evaporation using biodegradable and biocompatible LTPU. This polymer was pre-synthesized through the use of an amino acid-based chain extender, desaminotyrosyl L-threonine hexyl ester (DLTHE), where urethane bonds are formed by poly(lactic acid)-poly(ethylene glycol)-poly(lactic acid) (PLA-PEG-PLA) triblock copolymer and 1,6-hexamethylene diisocyanate (HDI). LTPU is designed to be degraded by hydrolysis and enzymatic activity due to the presence of ester bonds and peptide bonds within the polymer backbone.
View Article and Find Full Text PDFMaterials (Basel)
January 2025
Polymer Chemistry and Physics Research Group, Institute of Materials and Environmental Chemistry, HUN-REN Research Centre for Natural Sciences, Magyar Tudósok Körútja 2, H-1117 Budapest, Hungary.
Tuning the critical solution temperature (CST) of thermoresponsive polymers is essential to exploit their immense potential in various applications. In the present study, the effect of PEG-methyl ether methacrylate with a higher molecular weight of 1100 g/mol (mPEGMA) as a comonomer was investigated for its suitability for the CST adjustment of LCST-type polymers. Accordingly, a library of mPEGMA-based copolymers was established with varying compositions () using four main comonomers, namely di(ethylene glycol) ethyl ether acrylate, -isopropyl acrylamide and methacrylamide, and mPEGMA, with different CST values (cloud points, , and clearing points, , by turbidimetry).
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