A Study Of A Self-Assembledpolyasparticacid Nanoparticles For Targeted Delivery Of Doxorubicin

Nanopartiele drug delivery system refers to after embedding the natural or synthetic macromolecular and high polymer materials such as drugs, proteins and small interference RNA, through the cell swallowing function to improve blood transportation function and targeted therapy. Polyaspartic Acid as a synthetic polymer biomaterial, has good biocompatibility,it will release the non-toxic harmLess natural amino acid with the degradation of main chain.In order to prepare a pH-responsive and tumor-targeted copolymer,polyaspartic acid (PASP) was conjugated with hydrophobic L-histidine (His),then folic acid was used to improve tumor targeting.Folate-modified polyaspartic acid-g-histidine (FA-PASP-His)was used as a carrier foranti-cancer drugs. The effect of the degree of substitution(DS)on the pH-responsive behaviour of FPHnanoparticles was confirmed by studies of nanoparticles of different sizes. Doxorubicin(DOX) loaded FPH micelles were prepared by ultrasonic dispersion and diafiltration methods,In vitro drug releasestudies demonstrated that DOX was released from FPH micelles in a pH-dependentmanner. FPH with a 18% loading capacity displayed. At pH values below 7.0, the cumulative DOX release and cell cytotoxicity were increased compared to those at physiological pH. In vitro cytotoxicity assays showed that all the blank micelles were nontoxic. However, MTTassay and FCM tests against HeLa cells and HepG2 cells showed thatDOX-loaded nanoparticleswere highly cytotoxic. FPH micelles are a promising nanosystem for the intracellular targeted delivery of DOX.