Preparation of silver nanoparticles using aqueous extracts of the red algae Laurencia aldingensis and Laurenciella sp. and their cytotoxic activities

Abstract

This paper describes the preparation of silver nanoparticles (AgNPs) through an environmentally friendly route, using a disposable aqueous extract of seaweed as a reducing agent. The seaweeds used were Laurencia aldingensis and Laurenciella sp., and the AgNPs obtained from both algae were characterized by UV–vis spectroscopy, energy-dispersive X-ray (EDX), X-ray diffraction (XRD), high-resolution transmission electron microscopy (HRTEM), and zeta potential measurements. Furthermore, cell viability assays were carried out to assess the cytotoxicity of these AgNPs on the P4 human foreskin fibroblast cell line, as well as on human uterine sarcoma (MES-SA) and the corresponding doxorubicin-resistant mutant MES-SA/Dx5 cells. High toxicity was observed in both of the tested cancer cell lines with very similar half maximal inhibitory concentration (IC50) values (1- to 4 μM range); however, no toxicity was observed in the P4 cells. The alternative synthetic method proposed in this work allows the use of renewable and disposable algae extracts, which leads to the preparation of AgNP with remarkable cytotoxicity against sarcoma tumor cells.