| Gel is a three-dimensional network which consists of solvent and polymer. The polymer contains ionic, hydrogen or hydrophobic group on its main or side chains. Gels which use water as solvent are called hydrogels. As its good biocompatibility, hydrogels have a wide range of applications in the health sector.Nanogels are crosslinked polymer gel particles possessing an average diameter in the range of 1?1000 nm. The nanogel dispersions often have low viscosity and shear thinning property. In addition, thermosensitive nanogel dispersions often possess stronger temperature sensitivities and faster temperature response compared with thermosensitve polymer solution, which make an attractive potential to be applied in biomedical engineering.This paper combined hydrogelator which is laboratory synthesized and PNIPAAm nanogel dispersions, namely combined general supramolcular hydrogel and nanogel,in order to find a way on gelation PNIPAAm nanogel dispersions in the low concentration and viscosity. The main contents and results are as follows:(1)The paper synthesized a low-molecular-weight hydrogelator L-phenylalanine derivatives TC18PheBu which can gelate pH2 or pH7 water in low concentration.(2)Successfully gelated PNIPAAm nanogel dispersions using the hydrogelator TC18PheBu, inspected the lowest gelation concentration of the gel and the phase transition temperature, used DSC, POM, TEM to study of thermal properties, crystals and micro structure. These results indicated that dispersion gel gelation process is that PNIPAAm nanogel particles expanded from the globule to coil at first, and then the gelator self-assembled under the nanogel particles'interaction and space limitation, maked the dispersion gelate.(3)Used salicylic acid as a model drug, inspected thermo-sensitive nanogel dispersion gel of the drug release, and the affecting factors, found dispersion gel with the temperature sensitivity of drug release. |
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