TY - JOUR
T1 - In vivo versus in vitro degradation of controlled release polymers for intracranial surgical therapy
AU - Wu, Mary P.
AU - Tamada, Janet A.
AU - Brem, Henry
AU - Langer, Robert
PY - 1994/3
Y1 - 1994/3
N2 - Intracranial studies to analyze the degradation kinetics of the bioerodible polymer poly[bis(p‐carboxyphenoxy)propane‐sebacic acid] [p(CPP‐SA) 20:80] copolymer wafers were conducted in a rat model. Rats were separated into four groups: those receiving (1) polymer, (2) polymer loaded with the chemotherapeutic agent BCNU,(3) drugloaded polymer with previous tumor implantation, and (4) polymer and an absorbable hemostatic material. A polymer wafer was surgically implanted into the brain of each animal. Residual polymer was harvested at varying times for chromatographic analysis. In vitro effects of pH, mixing, and water availability on degradation were also studied. The results of in vitro and in vivo studies were compared to understand the behavior of polymers in a clinical setting. We found that degradation of p(CPP‐SA) initially occurred more slowly in vivo than in vitro. The presence of BCNU, tumor, and absorbable hemostatic material did not affect the ultimate time of polymer degradation in vivo, and the intrinsic polymer degradation time of 1 mm thick p(CPP‐SA) 20:80 disks in vivo was 6–8 weeks. © 1994 John Wiley & Sons, Inc.
AB - Intracranial studies to analyze the degradation kinetics of the bioerodible polymer poly[bis(p‐carboxyphenoxy)propane‐sebacic acid] [p(CPP‐SA) 20:80] copolymer wafers were conducted in a rat model. Rats were separated into four groups: those receiving (1) polymer, (2) polymer loaded with the chemotherapeutic agent BCNU,(3) drugloaded polymer with previous tumor implantation, and (4) polymer and an absorbable hemostatic material. A polymer wafer was surgically implanted into the brain of each animal. Residual polymer was harvested at varying times for chromatographic analysis. In vitro effects of pH, mixing, and water availability on degradation were also studied. The results of in vitro and in vivo studies were compared to understand the behavior of polymers in a clinical setting. We found that degradation of p(CPP‐SA) initially occurred more slowly in vivo than in vitro. The presence of BCNU, tumor, and absorbable hemostatic material did not affect the ultimate time of polymer degradation in vivo, and the intrinsic polymer degradation time of 1 mm thick p(CPP‐SA) 20:80 disks in vivo was 6–8 weeks. © 1994 John Wiley & Sons, Inc.
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U2 - 10.1002/jbm.820280314
DO - 10.1002/jbm.820280314
M3 - Article
C2 - 8077254
AN - SCOPUS:0028400602
VL - 28
SP - 387
EP - 395
JO - Journal of Biomedical Materials Research
JF - Journal of Biomedical Materials Research
SN - 1552-4973
IS - 3
ER -