RGD-Conjugated Silica Nanoparticles for Potentially Targeted Delivery of Quercetin to HeLa Cancer Cells

Abstract

Purpose

To overcome the main limitation of Quercetin (QUR), such as its poor water solubility, low bioavailability, and instability which affect its therapeutic use. QUR was encapsulated into commercially available silica nanoparticles (SNs) and subsequently surface-conjugated with the Arg-Gly-Asp (RGD) peptide to obtain SNs-QUR and SNs-QUR-RGD, respectively.

Methods

Encapsulation efficiency, loading capacity, and in vitro drug release were determined by UV spectroscopy, while successful RGD conjugation was verified by FT-IR analysis. Particle size, zeta potential, and polydispersity index (PDI) were evaluated using dynamic light scattering (DLS) to assess the physicochemical properties and colloidal stability of the formulations. The cytotoxic activity of free QUR, SNs-QUR, and SNs-QUR-RGD against HeLa cervical cancer cells was investigated using the MTT assay.

Results

The encapsulation efficiency and loading capacity of QUR in SNs were approximately 55.7% and 0.11%, respectively. FT-IR spectra confirmed the successful attachment of RGD to the nanoparticle surface. DLS results revealed an increase in mean particle size following QUR loading and further enlargement after RGD conjugation, while zeta potential and PDI values indicated good stability and moderate size uniformity. In Vitro Release studies demonstrated a sustained release pattern for SNs-QUR-RGD, which was slower than that of SNs-QUR, whereas free QUR showed the fastest release. Moreover, SNs-QUR-RGD exhibited enhanced cytotoxicity compared with SNs-QUR and free QUR, highlighting its potential as an efficient targeted nanocarrier for hydrophobic anticancer drugs.

Conclusion

The SNs-QUR-RGD exhibited efficient drug encapsulation, sustained release and enhanced cytotoxicity against HeLa cells, highlighting its potential as a promising targeted nanocarrier for the delivery of QUR and other hydrophobic anticancer agents.