Research Article

Safety Evaluation of Engineered Nanomaterials for Health Risk Assessment: An Experimental Tiered Testing Approach Using Pristine and Functionalized Carbon Nanotubes

Figure 2

A549 cells examined by calcein/PI staining. (a) Untreated cells. Representative micrographs showing cell preparations after 24 h exposure to 100 μg/mL: (b) pristine MWCNT; (c) MW-COOH: laboratory-made carboxyl functionalized nanotubes; (d) SiO2: silica; (e) CB: carbon black; (f) MW-NH2: laboratory-made amino-containing functionalized nanotubes. Viable (green) and damaged (red) cells are shown. Objective Magnification: 32x ( 4).
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