Bilirubin and Glycol Chitosan Conjugate Nanoparticle Loaded with Manganese Oxide and Chlorin e6 for Radiodynamic Therapy

Tumor hypoxia can negatively impact the effectiveness of radiation therapy. One approach is to use manganese oxide nanoparticle (MGN) to increase the oxygenation of the tumor prior to radiation and photodynamic (PDT) therapy. In this study, we synthesized of bilirubin conjugated to chitosan (ChiBil) loaded with Chlorin e-6 (Ce-6) and MGN to analyze the therapeutic potential in CT-26 colon cancer model. ChiBil-MGN-Ce6 in vitro analysis for hypoxia reduction showed significant difference in hypoxia in CT-26 cancer cells compared to control. In CT-26 subcutaneous tumor mice model ChiBil-MGN-Ce6 was injected at 10mg/kg [MGN] concentration and PDT/radiotherapy was performed to get a significant tumor growth inhibition. T1 contrast effect of MGN was also observed in nanoparticle injected mice. According to these findings, ChiBil-MGN-Ce6 may increase the efficacy of PDT/radiotherapy by reducing hypoxia in colon cancer..