Preparation of Poly(N-isopropylacrylamide) -g-Polyamidoamine dendrimer derivative and it’s drug release behaviors
The purpose of the investigation was to develop a novel dendrimer derivative of Poly(Nisopropylacrylamide) (PNIPAAm)-g-polyamidoamine (PAMAM) as a kind of nano-scale drug delivery device for increasing the solubility of the hydrophobic drugs and controlling the release of the drugs. PAMAM dendrimer was synthesized from ethylenediamine (EDA) on the basis of repeatedly using two consecutive chain forming reactions: the michael addition reaction and the amine reaction. The resulted G2.0 PAMAM-OH was characterized by mass spectrum (MS) and 1H NMR. The thermosensitive PNIPAAm with carboxyl terminal group was obtained by using mercaptoacetic acid (MAA) as a chain-transfer agent, and 2,2亴-azobisiso-butyronitrile (AIBN) as an initiator, which was then grafted to the PAMAM dendrimers in the presence of 1-(3-dimethylaminopropyl)-3-ethylcarbodiimide hydrochloride (EDC丒HCl) through esterification. The structure of this thermosensitive PNIPAAm- grafted dendrimer was characterized by 1H NMR and the molecular weight was determined by GPC. The thermosensitive properties of the resulted dendrimer derivatives determined by UV-vis photometer showed a little bit different from the PNIPAm and the temperature-controlled drug release behaviors were studied by using the hydrophobic indomethacin as a model drug. The results indicated that the lower critical solution temperature (LCST) of the PAMAM derivatives was about 32 oC, which is a little bit lower than that of PNIPAAm. The release rate of the drug loaded in the internal cavities of the PAMAM derivatives could be effectively controlled by adjusting the surrounding temperature below or above the LCST. The thermosensitive PNIPAAm chains grafted on the surface of PAMAM dendrimer could act as a channel switching on-off button through expending or contracting in response to the temperature change. This kind of PNIPAm-g-PAMAM-OH dendrimer derivative is desirable to be used in the controlled drug release systems.
PAMAM dendrimer derivative PNIPAAm Thermosensitive Controlled drug release
Wang Zheng Zhou Bo Fan Xiang-pan Shen Li
Tianjin Key Laboratory for Modern Drug Delivery & High-Efficiency School of Pharmaceutical Science and Technology, Tianjin University
国际会议
International Symposium on Crystal Engineering and Drug Delivery System 2009(2009晶体工程与药物传送系统国际会议)
天津
英文
433-434
2009-09-05（万方平台首次上网日期，不代表论文的发表时间）