RESUMO
Tamoxifen is the drug of choice as hormonal therapy for hormone receptor-positive breast cancers and can reduce the risk of breast cancer recurrence. However, oral tamoxifen has a low bioavailability due to liver and intestinal metabolic passes. To overcome this problem and utilize the potential of this drug to its maximum, inorganic nanoparticle carriers have been exploited and tested to increase its bioavailability. Biocompatibility and unique magnetic properties make iron oxide nanoparticles an excellent choice as a drug delivery system. In this study, we developed and tested a "green synthesis" approach to synthesize iron nanoparticles from green tea extract and coated them with agar for longer stability (AG-INPs). Later, these hybrid nanoparticles were conjugated with tamoxifen (TMX). By using this approach, we synthesized stable agar-coated tamoxifen-conjugated iron nanoparticles (TMX-AG-INPs) and characterized them with Fourier-transform infrared (FTIR) spectroscopy. The average particle size of AG-INPs was 26.8 nm, while the average particle size of tamoxifen-loaded iron nanoparticles, TMX-AG-INPs, was 32.1 nm, as measured by transmission and scanning electron microscopy. The entrapment efficiency of TMX-AG-INPs obtained by the drug release profile was 88%, with a drug loading capacity of 43.5%. TMX-AG-INPs were significantly (p < 0.001) efficient in killing breast cancer cells when tested in vitro on the established breast cancer cell line MCF-7 by cell viability assay, indicating their potential to control cell proliferation.