Restructuring of chitosan for the delivery of ³²P to hepatoma cells

Therapeutic radionuclides used in the radiation ablation of hepatocellular carcinoma (HCC) face challenges of self-targeting and heterogenous dose distribution. ³²P, a potent b emitter with several desirable features of coordination with cellular biomolecules, can easily overcome the challenge of dose distribution. However, a major hurdle in this direction is to effectively deliver ³²P into the target tissue. Hence, this study is an attempt to successfully modify chitosan for the delivery of ³²P to HCC cells. The study aims to design a polymer–ligand-based system for ³²P delivery to hepatoma cells. Chitosan was modified through phosphorylation with 85% orthophosphoric acid to form phosphorylated chitosan (PC). PC was then grafted with ligand lactobionic acid to obtain phosphorylated, galactosylated chitosan (P-GC). Phosphorous per gram of the compound was determined spectrophotometrically. Free amino groups of unmodified chitosan and P-GC were qualitatively investigated. Compound was characterized through FTIR. Spectrophotometric tests for phosphorous indicated successful phosphorylation of chitosan. Qualitative test for amino groups revealed the formation of amide bond in the compound. IR spectra of PC and P-GC further confirmed the phosphorylation and grafting of lactobionic acid to the chitosan. ³²P-labeled galactosylated chitosan can be synthesized through similar mechanism and aimed to target the hepatocytes