Flow cytometer dot plots of apoptosis-necrosis of SNU-1 cells upon treatment with different beads for 24 h.

Representative dot plots of Annexin V and PI staining obtained from flow cytometric analyses of cells treated for 24 h with 50–200 nm particles or blank (A) or 500–5000 nm particles (B). The upper right quadrant represents cells at late stage of apoptosis or undergoing necrosis.

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