Polymer Grafted Porous Silicon Particles for Cancer Therapy

This thesis explores how modifying porous silicon nanoparticles (pSiNPs) can improve breast cancer treatment. The research develops two innovative delivery systems to overcome current challenges like drug resistance and toxicity. Chapter 1 reviews nanoparticle delivery systems for breast cancer, focusing on surface modifications and targeting strategies. Chapter 2 presents polymer-grafted pSiNPs for siRNA delivery, showing high loading capacity (438 μg/mg) and protection against degradation. This system effectively delivered PLK1 siRNA to breast cancer cells, reducing cell viability through gene silencing. Chapter 3 develops a theranostic platform combining MRI imaging with pH-responsive drug delivery. By functionalising pSiNPs with Gd-DOTA complexes and pH-responsive polymers, the system achieved controlled paclitaxel release and enhanced MRI contrast in acidic tumour environments, showing better cytotoxicity than free paclitaxel. Chapter 4 summarizes findings and discusses future research directions.