Impact of copolymer ratio on drug distribution in styrene-isobutylene-styrene block copolymers.

  title={Impact of copolymer ratio on drug distribution in styrene-isobutylene-styrene block copolymers.},
  author={Martin K. Mcdermott and Chang-soo Kim and David M Saylor and Dinesh V. Patwardhan},
  journal={Journal of biomedical materials research. Part B, Applied biomaterials},
  volume={101 7},
Drug-polymer composite coatings, composed of styrene-isobutylene-styrene (SIBS) tri-block copolymers, are frequently used in controlled drug release biomedical device applications. In this work, we used atomic force microscopy to characterize the effects of different drug loadings and polymer chemistries (i.e., block copolymer ratio) on the variation of surface structures and compositions of SIBS-tetracycline (SIBS-TC) cast composites including tetracycline (TC) drug amount, drug phase size… Expand
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Microstructure and elution of tetracycline from block copolymer coatings.
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Physical characterization of controlled release of paclitaxel from the TAXUS Express2 drug-eluting stent.
The polymer carrier technology in the TAXUS drug-eluting stent consists of a thermoplastic elastomer poly(styrene-b-isobutylene-b-styrene) (SIBS) with microphase-separated morphology resulting inExpand
Modeling microstructure development and release kinetics in controlled drug release coatings.
The results suggest that improved comprehension and quantification of the physico-chemical properties in controlled release systems will enable the microstructure to be tailored to achieve desired responses that are insensitive to manufacturing variations. Expand
Styrenic block copolymers for biomaterial and drug delivery applications.
Poly (styrene-b-isobutylene- b-styrene) block copolymer has critical enabling properties related to processing, vascular compatibility and bio-stability that has resulted in its use as the matrix for paclitaxel delivery from Boston Scientific's TAXUS coronary stent. Expand
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Detailed optical and scanning electron microscopic analysis of stents explanted from rabbit and porcine models showed that the SIBS coating maintained physical integrity, and intentional defects introduced into the stent coating were shown to have only a minimal impact on PTx release. Expand
Application of coherent anti-Stokes Raman scattering microscopy to image the changes in a paclitaxel-poly(styrene-b-isobutylene-b-styrene) matrix pre- and post-drug elution.
Results indicate that paclitaxel was dissolved and depleted from the SIBS film during in vitro drug elution, supporting the use of CARS microscopy as an effective nondestructive technique for chemical imaging of pac litaxel elution dynamics in polymer films. Expand
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Adhesion of Styrene-Isobutylene-Styrene (SIBS) triblock copolymers to polystyrene and polypropylene was investigated at controlled ratios and molecular weights of the SIBS's polystyrene. ComparativeExpand