Abstract
Three triblock copolymers based on the poly(lactide) or poly(lactide-co-glycolide) and poly(ethylene glycol) or poly(ethylene oxide) blocks were synthesized and characterized. The weight average molecular weight and number average molecular weight were determined by gel permeation chromatography and proton nuclear magnetic resonance spectroscopy, respectively. Fourier transform infrared spectroscopy was used to determine the completion of synthesis of polymers. Thermoreversible sol-gel transition temperature and concentration were determined by an inverted tube method. Two formulations each of three synthesized polymers containing 5% (w/v) of lysozyme or bromelain but differing in polymer concentrations (20-30%, w/v) were prepared and studied for in vitro release of the incorporated protein. In vitro biocompatibility of the delivery systems was studied by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) cell viability assay. Biological activities of lysozyme and bromelain were determined by enzyme activity assays. Critical gelling concentrations were found in the range of 20-30% (w/v). In vitro biocompatibility study showed that all the formulations were biocompatible. Increasing the polymer concentration led to a decrease in burst release and extended the in vitro release of proteins. Furthermore, biological activities of lysozyme and bromelain in released samples were found to be significantly (p <0.05) greater in comparison to the control. Thus, the above thermosensitive polymers were able to deliver proteins in biologically active forms at a controlled rate for 2-8 weeks.
| Original language | English |
|---|---|
| Pages (from-to) | 68-77 |
| Number of pages | 10 |
| Journal | International Journal of Pharmaceutics |
| Volume | 341 |
| Issue number | 1-2 |
| DOIs | |
| State | Published - Aug 16 2007 |
Fingerprint
All Science Journal Classification (ASJC) codes
- Pharmaceutical Science
Cite this
Thermosensitive polymers : Synthesis, characterization, and delivery of proteins. / Singh, Somnath; Webster, Dean C.; Singh, Jagdish.
In: International Journal of Pharmaceutics, Vol. 341, No. 1-2, 16.08.2007, p. 68-77.Research output: Contribution to journal › Article
}
TY - JOUR
T1 - Thermosensitive polymers
T2 - Synthesis, characterization, and delivery of proteins
AU - Singh, Somnath
AU - Webster, Dean C.
AU - Singh, Jagdish
PY - 2007/8/16
Y1 - 2007/8/16
N2 - Three triblock copolymers based on the poly(lactide) or poly(lactide-co-glycolide) and poly(ethylene glycol) or poly(ethylene oxide) blocks were synthesized and characterized. The weight average molecular weight and number average molecular weight were determined by gel permeation chromatography and proton nuclear magnetic resonance spectroscopy, respectively. Fourier transform infrared spectroscopy was used to determine the completion of synthesis of polymers. Thermoreversible sol-gel transition temperature and concentration were determined by an inverted tube method. Two formulations each of three synthesized polymers containing 5% (w/v) of lysozyme or bromelain but differing in polymer concentrations (20-30%, w/v) were prepared and studied for in vitro release of the incorporated protein. In vitro biocompatibility of the delivery systems was studied by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) cell viability assay. Biological activities of lysozyme and bromelain were determined by enzyme activity assays. Critical gelling concentrations were found in the range of 20-30% (w/v). In vitro biocompatibility study showed that all the formulations were biocompatible. Increasing the polymer concentration led to a decrease in burst release and extended the in vitro release of proteins. Furthermore, biological activities of lysozyme and bromelain in released samples were found to be significantly (p <0.05) greater in comparison to the control. Thus, the above thermosensitive polymers were able to deliver proteins in biologically active forms at a controlled rate for 2-8 weeks.
AB - Three triblock copolymers based on the poly(lactide) or poly(lactide-co-glycolide) and poly(ethylene glycol) or poly(ethylene oxide) blocks were synthesized and characterized. The weight average molecular weight and number average molecular weight were determined by gel permeation chromatography and proton nuclear magnetic resonance spectroscopy, respectively. Fourier transform infrared spectroscopy was used to determine the completion of synthesis of polymers. Thermoreversible sol-gel transition temperature and concentration were determined by an inverted tube method. Two formulations each of three synthesized polymers containing 5% (w/v) of lysozyme or bromelain but differing in polymer concentrations (20-30%, w/v) were prepared and studied for in vitro release of the incorporated protein. In vitro biocompatibility of the delivery systems was studied by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) cell viability assay. Biological activities of lysozyme and bromelain were determined by enzyme activity assays. Critical gelling concentrations were found in the range of 20-30% (w/v). In vitro biocompatibility study showed that all the formulations were biocompatible. Increasing the polymer concentration led to a decrease in burst release and extended the in vitro release of proteins. Furthermore, biological activities of lysozyme and bromelain in released samples were found to be significantly (p <0.05) greater in comparison to the control. Thus, the above thermosensitive polymers were able to deliver proteins in biologically active forms at a controlled rate for 2-8 weeks.
UR - http://www.scopus.com/inward/record.url?scp=34447639976&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=34447639976&partnerID=8YFLogxK
U2 - 10.1016/j.ijpharm.2007.03.054
DO - 10.1016/j.ijpharm.2007.03.054
M3 - Article
VL - 341
SP - 68
EP - 77
JO - International Journal of Pharmaceutics
JF - International Journal of Pharmaceutics
SN - 0378-5173
IS - 1-2
ER -