The Preparetion Of Thermo Responsive ZnO@PNIPAM Hybrid Nanoparticles And Its Application In Drug Delivery

ZnO is an inorganic metal oxide semiconductor with large excitation bindingenergy and wide band gap, and it’s also cheap, environmentally friendly andnon-toxic. These advantages make it has promising future in photoelectric area andbiomedicine especially in drugs’ delivery and release et al. However, due to ZnO ishydrophobic and oleophobic, it cannot be well dispersed and restrict its application.So it is meaningful to suface modificated with ZnO to improve its proterty. The maincontents as follows:We have prepared ZnO-NH2by sol-gel, then the ZnO-NH2nanoparticles reactedwith2-bromoisobutyryl bromide to get the ZnO-Br as initiator. Next, the thermalresponsive poly(N-isopropylacrylamide)(PNIPAM) grafted on ZnO nanoparticles viasurface-initiated atom transfer radical polymerization (ATRP) to prepare theZnO@PNIPAM core-shell nanoparticles. The structure is characterized by FT-IR andXRD. The thermogravimetric analysis (TGA) shows that the grafting amount ofPNIPAM was about38%. PNIPAM is well water-soluble under low critical solutiontemperature (LCST), so after grafting PNIPAM the SEM images show thatnanoparticles improve its dispersion. The responsive properties of ZnO@PNIPAMwere measured by photoluminescence spectra, and the results demonstrated that thePNIPAM chains grafted on ZnO surfaces can realize its reversible thermal responsiveand photoluminescence properties. An anticancer drug, doxorubicin (Dox), was usedas a model drug and loaded into the hybrid nanoparticles, and the in vitro drug releasetest implied that the ZnO@PNIPAM could work as a thermal responsive drugdelivery system. Furthermore, pH sensitive drug releases were carried out in acetatebuffer at pH5.0, pH6.0respectively and in the water, pH7.0, and the results showedevident pH dependency, showing its pH responsive properties.