Chitosan mediated 5-Fluorouracil functionalized silica nanoparticle from rice husk for anticancer activity

Herein, we have reported a cost-effective method of synthesizing highly efficient silica nanomaterial from rice husks for its application as a chemotherapeutic agent. Silica particle with two different sizes ~20 nm and ~40 nm were achieved from silica precursor obtained from rice husk. 5-Fluorouracil was functionalized onto the surface of silica nanoparticles by direct conjugation and chitosan mediated conjugation. Particle size analysis, zeta potential and functional analyzes were performed in systematic methodology to confirm chitosan coating and 5-Fluorouracil conjugation on silica nanoparticles. The drug loading percentage with respect to the particle size shows that ~20 nm particles have higher loading capacity. The chitosan mediated conjugation of drug shows sustained release in acidic pH and hence suitable for cancer cell-targeted delivery. The in vitro cell culture studies performed on MC3T3 fibroblast cell lines, MCF-7 and A549 cancer cell lines depicts that, compared to direct conjugation of 5-Fluorouracil, chitosan mediated drug conjugation on the surface of silica nanoparticles shows lesser toxic to fibroblast cell lines and higher toxicity towards cancer cell lines. The results of this toxicity were also confirmed from the nucleic acid spectral signature of Raman spectra treated with drug conjugated silica nanoparticles.