Thermosensitive PEG–PCL–PEG Hydrogel Controlled Drug Delivery System: Sol–Gel–Sol Transition and In Vitro Drug Release Study

• Published in: Journal of pharmaceutical sciences Vol. 98; no. 10; pp. 3707 - 3717
• Main Authors: Gong, Chang Yang, Dong, Peng Wei, Shi, Shuai, Fu, Shao Zhi, Yang, Jin Liang, Guo, Gang, Zhao, Xia, Wei, Yu Quan, Qian, Zhi Yong
• Format: Journal Article
• Language: English
• Published: Hoboken Elsevier Inc 01.10.2009; Wiley Subscription Services, Inc., A Wiley Company; Wiley; American Pharmaceutical Association
• Subjects: Acids - chemistry; biodegradable polymers; Biological and medical sciences; Chromatography, Gel; Delayed-Action Preparations; Drug Delivery Systems; drug release; General pharmacology; Hot Temperature; hydrogel; Hydrogels - chemistry; Hydrogen-Ion Concentration; injectable; Magnetic Resonance Spectroscopy; Medical sciences; Microscopy, Electron, Scanning; Molecular Weight; Pharmaceutical technology. Pharmaceutical industry; Pharmacology. Drug treatments; Polyesters - chemistry; Polyethylene Glycols - chemistry; protein delivery; Rheology; Serum Albumin, Bovine - administration & dosage; Serum Albumin, Bovine - chemistry; Sodium Chloride - chemistry; sol-gel-sol transition; Spectroscopy, Fourier Transform Infrared; Temperature; thermosensitive; Vitamin B 12 - administration & dosage; Vitamin B 12 - chemistry; injectable; sol–gel–sol transition; hydrogel; protein delivery; biodegradable polymers; thermosensitive; drug release; Drug; Pharmaceutical technology; sol-gel-sol transition; Biodegradability; Controlled release form; Polymer; Drug carrier; In vitro; Thermal labile product; Protein; Ethylene oxide polymer; Colloidal gel; Dosage form; Hydrogel; Release
• ISSN: 0022-3549; 1520-6017; 1520-6017
• DOI: 10.1002/jps.21694

In this article, biodegradable and low molecular weight poly(ethylene glycol)–poly(ε-caprolactone)–poly(ethylene glycol) (PEG–PCL–PEG, PECE) triblock copolymers were successfully synthesized. Aqueous solution of the obtained PECE copolymers underwent sol–gel–sol transition as temperature increased which was flowing sol at room temperature and then turned into nonflowing gel at body temperature. Sol–gel–sol phase transition behaviors of aqueous PECE solutions were studied using rheometry and test tube-inverting method, which were affected by many factors, including the heating/cooling procedure and different additives in copolymers aqueous solution. In vitro drug release behavior was studied using bovine serum albumin (BSA) and Vitamin B12 (VB12) as model drugs, and the PECE hydrogel could protect BSA from acidic degradation for 1 week at least. Therefore, PECE hydrogel is believed to be promising for injectable in situ gel-forming controlled drug delivery system due to their great thermosensitivity and biodegradability. © 2009 Wiley-Liss, Inc. and the American Pharmacists Association J Pharm Sci 98:3707–3717, 2009