Uptake and toxicity studies of poly-acrylic acid functionalized silicon nanoparticles in cultured mammalian cells

Abstract

Poly-acrylic acid (PAAc) terminated silicon nanoparticles (SiNPs) have been synthes zed and employed as a synchronous fluorescent signal indicator in a series of cultured m mmalian cells: HHL5, HepG2 and 3T3-L1. Their biological effects on cell growth and proliferation in both human and mouse cell lines have been studied. There was no evidence of i vitro cytotoxity in the cells exposed to PAAc terminated SiNPS when assessed by cell mor hology, cell proliferation and viability, and DNA damage assays. The uptake of the nanoc ystals by both HepG2 and 3T3-L1 cells was investigated by confocal microscopy and flow c tometry, which showed a clear time-dependence at higher concentrations. Reconstructed 3- confocal microscope images exhibited that the PAAc-SiNPs were evenly distributed through ut the cytosol rather than attached to outer membrane. This study provides fundamental e idence for the safe application and further modification of silicon nanoparticles, which could broaden their application as cell markers in living systems and in micelle encapsu ated drug delivery systems. © 2012 WILEY-VCH Verlag GmbH & Co.