As the removal of intact Microcystis 3X FLAG tag Peptide without causing cell lysis significantly avoids the addition of dissolved toxins and intracellular organics into the treated water , it is significant to evaluate the influence of KMnO4 oxidation on the cell integrity. Fig. 2 shows Flow cytometry results of the raw and KMnO4-treated cells. In Fig. 2(a)–(c), FL3-A corresponds to chlorophy II autofluorescence detected at 630 nm, and FL1-A corresponds to SYTOX green stain fluorescence detected at 530 nm. P1 and P11 are regions used to define lysed and live populations, respectively  and . It can be observed in Fig. 2(a) that the intact cells in the original cell solution account for 94.0% of the total cell count, while that the damaged cells take a percentage of 5.6%. Since parts of cells would naturally die owing to metabolism, it is reasonable to find a small part of damaged cells in the raw cell solution. When the cells were treated by KMnO4 at the doses of 1.0 mg/L and 2.0 mg/L for 20 min, proportions of intact cells were 93.3% and 94.9%, respectively.