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Title: INVESTIGATION OF DRUG RELEASE FROM BIODEGRADABLE PLG MICROSPHERES: EXPERIMENT AND THEORY

Abstract

Piroxicam containing PLG microspheres having different size distributions were fabricated, and in vitro release kinetics were determined for each preparation. Based on the experimental results, a suitable mathematical theory has been developed that incorporates the effect of microsphere size distribution and polymer degradation on drug release. We show from in vitro release experiments that microsphere size has a significant effect on drug release rate. The initial release rate decreased with an increase in microsphere size. In addition, the release profile changed from first order to concave-upward (sigmoidal) as the system size was increased. The mathematical model gave a good fit to the experimental release data.

Authors:
 [1];  [1];  [1];  [1]
  1. Los Alamos National Laboratory
Publication Date:
Research Org.:
Los Alamos National Lab. (LANL), Los Alamos, NM (United States)
OSTI Identifier:
985891
Report Number(s):
LA-UR-07-0642
TRN: US201017%%69
DOE Contract Number:
AC52-06NA25396
Resource Type:
Conference
Resource Relation:
Conference: ASME SUMMER BIO-ENGINEERING CONFERENCE 2007 ; 200706 ; KEYSTONE
Country of Publication:
United States
Language:
English
Subject:
56; DISTRIBUTION; IN VITRO; KINETICS; MATHEMATICAL MODELS; MICROSPHERES; POLYMERS

Citation Formats

ANDREWS, MALCOLM J., BERCHANE, NADER S., CARSON, KENNETH H., and RICE-FICHT, ALLISON C. INVESTIGATION OF DRUG RELEASE FROM BIODEGRADABLE PLG MICROSPHERES: EXPERIMENT AND THEORY. United States: N. p., 2007. Web.
ANDREWS, MALCOLM J., BERCHANE, NADER S., CARSON, KENNETH H., & RICE-FICHT, ALLISON C. INVESTIGATION OF DRUG RELEASE FROM BIODEGRADABLE PLG MICROSPHERES: EXPERIMENT AND THEORY. United States.
ANDREWS, MALCOLM J., BERCHANE, NADER S., CARSON, KENNETH H., and RICE-FICHT, ALLISON C. Tue . "INVESTIGATION OF DRUG RELEASE FROM BIODEGRADABLE PLG MICROSPHERES: EXPERIMENT AND THEORY". United States. doi:. https://www.osti.gov/servlets/purl/985891.
@article{osti_985891,
title = {INVESTIGATION OF DRUG RELEASE FROM BIODEGRADABLE PLG MICROSPHERES: EXPERIMENT AND THEORY},
author = {ANDREWS, MALCOLM J. and BERCHANE, NADER S. and CARSON, KENNETH H. and RICE-FICHT, ALLISON C.},
abstractNote = {Piroxicam containing PLG microspheres having different size distributions were fabricated, and in vitro release kinetics were determined for each preparation. Based on the experimental results, a suitable mathematical theory has been developed that incorporates the effect of microsphere size distribution and polymer degradation on drug release. We show from in vitro release experiments that microsphere size has a significant effect on drug release rate. The initial release rate decreased with an increase in microsphere size. In addition, the release profile changed from first order to concave-upward (sigmoidal) as the system size was increased. The mathematical model gave a good fit to the experimental release data.},
doi = {},
journal = {},
number = ,
volume = ,
place = {United States},
year = {Tue Jan 30 00:00:00 EST 2007},
month = {Tue Jan 30 00:00:00 EST 2007}
}

Conference:
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