Photochemical effect of MB on the inactivation of E. coli in blood and biologic functions of blood cells / 第三军医大学学报

ABSTRACT

Objective To observe the photochemical effect of methylene blue (MB) on the inactivation of E. coli in blood and on biological functions of blood cells. Methods The blood was treated with 15 ?mol/L MB, 40 000 Lux halogen lamp irradiation and 0.35 mmol/l rutin for 10～40 min. The photochemical effect of MB on the inactivation of E.coli in blood was observed. The changes of biologic functions of blood cells were measured by means of RBC membrane binding to poly L lysine, reaction promoted by ATP enzyme and neutrophil phagocytosis tests. Results After treatment for 40 min, the E.coli count in blood decreased by 5 log units. The value of T/E of MB and irradiation of halogen lamp was higher than 1. No obvious changes of the morphology of blood cell were found. The negative electrical charges on membrane of RBC decreased by 11.23%～25.49%. After treatment of the blood for 20～30 min, the activity of Na + K +ATP enzyme of RBC membrane increased by 7.60%～20.07%. When the blood had been treated for 10～20 min, the positive rate of neutrophil phagocytosis enhanced by 9.00%. Conclusion MB photochemical treatment can effectively inactivate E. coli in blood. Under morphology specific condition of effectively inactivated blood bacteria, the shapes and functions of blood cells are not altered, but the RBC adhesion may increase by about 11.23%～25.49%.