The nanotoxicity investigation of optical nanoparticles to cultured cells in vitro

Abstract

Optical nanoparticles (NPs) have the potential to provide new tools for diagnosis and treatment of human diseases, however, their nanotoxicity and biological characteristics are still unclear. Here, we prepared a series of typical NPs (including gold nanospheres, gold nanorods, silver nanopheres, silver triangular nanoplates and quantum dots) with different material and surface chemical modification for nanotoxicity test. Cell proliferation was investigated by SRB assay where the NPs were co-cultured with cancer cells. It was found that NPs' toxicity was highly correlated to different factors-material selection, physical size/surface area, shape, and surface chemical property, etc. This work has the potential to provide a uniform and systematic information when they are applied as probes in biological and medical fields.

Keywords: CdTe/CdS quantum dots; Gold nanorods; Gold nanospheres; Hela cells; HepG2 cells; Nanotoxicity; SRB; Silver nanospheres; Silver triangular nanoplates.

Fig. 1

FESEM results of 15 (A) and 30 nm (B) GNSs, 15 nm × 44 nm GNRs (C), 30 nm SNSs (D) 60 nm STNPs (E) and TEM results of 2.5 nm GQDs (F) and 5 nm RQDs (G). The scale bar in (A)–(D) is 100 nm. The scale bar in (E) is 150 nm. The scale bar in (F) and (G) is 10 nm.

Fig. 2

The plasmon absorption spectra of 15 and 30 nm GNSs (A), 15 nm × 44 nm GNRs (B), 30 nm SNSs (C), 60 nm STNPs (D) and the absorption and emission spectra of 2.5 nm GQDs and 5 nm RQDs (E).

Fig. 3

Effect of gold NPs on cell viability and cell morphology in HepG2 and Hela cells. (A) 15 and 30 nm GNSs on cell viability in HepG2 cells. (B) GNRs on cell viability in HepG2 and Hela cells. (C) Comparison of 30 nm GNSs, CTAB-GNSs (45 nm) and CTAB-GNRs (15 nm × 44 nm) on cell viability in HepG2 cells. (D) HepG2 cell morphology in control (a), 30 nm GNSs (b), 45 nm CTAB-GNSs (c) and 15 nm × 44 nm CTAB-GNRs (d) after 48 h-treatment with the same concentration of 12.5 pM. The cell viability of control cells were set arbitrarily to 100%. The data plotted are mean ± standard error (SE), n = 8. *p < 0.05, **p < 0.01 vs. control group.

Fig. 4

Effect of silver NPs on cell viability and cell morphology in HepG2 and Hela cells. (A) SNSs and STNPs on cell viability in HepG2 and Hela cells. (B) HepG2 cell morphology in control (a), 200 μg/ml SNSs (b), 200 μg/ml STNPs (c) and Hela cells morphology in control (d), 200 μg/ml SNSs (e), 200 μg/ml STNPs (f) after 48 h-treatment. The cell viability of control cells were set arbitrarily to 100%. The data plotted are mean ± standard error (SE), n = 8. *p < 0.05, **p < 0.01 vs. control group.

Fig. 5

Effect of 2.5 nm and 5 nm CdTe/CdS core/shell QDs on cell viability and cell morphology in HepG2 cells. (A) 2.5 nm and 5 nm CdTe/CdS core/shell QDs on cell viability in HepG2 cells. (B) HepG2 cells morphology in control (a), GQDs (b) and RQDs (c) for 48 h-treatment with the same concentration of 0.1 μM. The cell proliferation of control cells were set arbitrarily to 100%. The data plotted are mean ± standard error (SE), n = 8. *p < 0.05, **p < 0.01 vs. control group.