title: A novel thermo-responsive drug delivery system with positive controlled release.
abstract: The model drug, 5-fluorouracil (5-FU) was loaded into the poly(N-isopropylacrylamide) (PNIPA) hydrogel at 25 degrees C, then the drug-loaded, swollen hydrogel sample was carefully enveloped in the dialysis bag to form a novel thermo-responsive drug delivery system (DDS). The concentration of released 5-FU was monitored at 266 nm on the UV spectrophotometer. We found that this novel DDS provides a positive drug release pattern and the drug, 5-FU, was released faster at the increased temperature (37 degrees C, >25 degrees C) than the one at the decreased temperature (10 degrees C, <25 degrees C). This was attributed to the double control of the thermo-sensitivity of the hydrogel matrix and the dialysis membrane. By employing the fast response PNIPA hydrogel instead of the conventional hydrogel in this novel DDS, we can further control the drug release rate and/or drug release amount etc., without changing the positive, thermo-responsive drug release pattern.
authors.affiliation: Department of Chemistry, Key Laboratory of Biomedical Polymer Materials of the Ministry of Education, Wuhan University, 430072, Wuhan, People's Republic of China. xz59@cornell.edu
authors.forename: Xian-Zheng
authors.initials: XZ
authors.lastname: Zhang
authors.forename: Ren-Xi
authors.initials: RX
authors.lastname: Zhuo
authors.forename: Jing-Zhou
authors.initials: JZ
authors.lastname: Cui
authors.forename: Jiao-Tao
authors.initials: JT
authors.lastname: Zhang
mesh_terms: D000970:Antineoplastic Agents / Q000008:administration & dosage / Q000493:pharmacokinetics; D003080:Cold Temperature; D003692:Delayed-Action Preparations / Q000008:administration & dosage / Q000493:pharmacokinetics; D016503:Drug Delivery Systems / Q000379:methods*; D005472:Fluorouracil / Q000008:administration & dosage / Q000493:pharmacokinetics; D006358:Hot Temperature; D020100:Hydrogels / Q000008:administration & dosage / Q000493:pharmacokinetics
chemical_list: D000970:Antineoplastic Agents; D003692:Delayed-Action Preparations; D020100:Hydrogels; D005472:Fluorouracil