Influence of bismuth nanoparticles on membrane cell of erythrocytes by AM Calcein assay and fluorescence microscopy. Blood cells were treated with same techniques described above. After 24 h of incubation, the erythrocytes were stained with AM Calcein and observed under fluorescence microscopy at 485 and 358 nm (Thornwood, NY). The images were analyzed by using AxioVision software (Thornwood, NY). The bar indicates 5 μm.