Abstract:【Objective】 Preparating magnetic nanoparticles loaded cisplatin with folate receptor targeted

magnetic targeting and pH sensitive release character (FA-PEG-NH-N=MNPs-CDDP)

which lays the foundation for the further development of intelligent drug carrier targeting head and neck tumor.【Methods】 Adopting chemical coprecipitation method to prepare Ferroferric oxide nanoparticles (MNP)modified by aldehyde sodium alginate

coordination complexation of sodium alga acid and Cisplatin on the surface of nano particles is carried on chemotherapeutic drug Cisplatin

meanwhile it prepares out double hydrazino-poly PEG

the carboxyl group of hydrazino-folate on one side of double hydrazino-poly PEG

obtaining folate -hydrazino poly PEG- diazanyl

then folate -hydrazino poly PEG- diazanyl connects the aldehyde group of sodium alga acid on MNP to wrap up drug

making Cisplatin to be hidden within carrier

obtaining PH sensitive carried Cisplatin magnetic nano intelligent targeting drug connecting folate decoration. Finally obtain Cisplatin carried magnetic nano drug targeted by folate receptor (FA-PEG-NH-N=MNPs-CDDP). Using ultraviole spectrophotometer

transmission electron microscopy

vibrating sample magnetometer and dynamic laserpatricle zize instrument their physicochemical properties were characterized while the cell targeting and pH sensitive release property were evaluated respectively by cells iron staining

transmission electron microscopy and vitro experiments. 【results】 The average magnetic nuclei particle size of pH sensitive Cisplatin-carried magnetic nano intelligent targeting drug connecting folate decoration is about (10.2 ± 1.5)nm

the average hydrodynamic diameter detected by laser particle size instrument is (176.6 ± 1.1)nm

Zeta electric potential is (-20.91 ± 1.76)mV

the content of Cisplatin is 0.773 mg?mL-1

content of iron is about 1.908 mg?mL-1

maximum saturated magnetization intensity is 16.3 ± 0.2emu.g-1. It is can be being uptaked by HNE-1 cells and respanded by lew pH. 【Conclusion】 This drug has drug has excellent stability and magnetic responsiveness

and releasing drug under low pH value while having pH sensitiveness.