ObjectiveTo investigate the bactericidal effect of loaded multifunctional povidoneiodine-nanometer selenium （PVP-I@Se） disinfectant on Staphylococcus aureus （SA） and methicillin-resistant Staphylococcus aureus （MRSA）， and to provide an experimental basis for the reduction of surgical site infection （SSI）. MethodsThe control group was the povidone iodine （PVP-I） group with different concentrations of iodine （50， 75， 100， 200 and 400 μg/mL）. The PVP-I@Se group （experimental group） was the PVP-I group further supplemented with 2 μg/mL Selenium nanoparticles （SeNPs）. Then we compared the bactericidal effect of the two groups of disinfectant solutions on SA and MRSA by examining the minimum inhibitory concentration （MIC）， minimum bactericidal concentration （MBC）， the shortest sterilization time at a concentration of 50 μg/mL iodine and the inhibition zone diameters at concentrations of 200 μg/mL and 400 μg/mL iodine. ResultsMIC values of PVP-I against SA and MRSA were both 79.17 μg/mL， and those of PVP-I@Se were 54.17 and 70.83 μg/mL， respectively. MBC values of PVP-I against SA and MRSA were 129.17 and 150.00 μg/mL， respectively， and those of PVP-I@Se were 70.83 and 87.50 μg/mL， respectively. At a concentration of 50 μg/mL iodine， the shortest sterilization time of PVP-I for SA and MRSA was 130 s and 140 s， respectively， and that of PVP-I@Se was 65 s and 75 s， respectively. At a concentration of 200 μg/ml iodine， the inhibition zone diameters of PVP-I for SA and MRSA were 7.67 mm and 8.33 mm， and those of PVP-I@Se were both 9.50 mm. At a concentration of 400 μg/mL iodine， the inhibition zone diameters of PVP-I for SA and MRSA were 9.00 mm and 9.33 mm， and those of PVP-I@Se were 11.67 mm and 12.00 mm， respectively. ConclusionsPVP-I with different concentrations of 50， 75， 100， 200 and 400 μg/mL iodine supplemented with 2 μg/mL SeNPs have better and faster bactericidal effect on SA and MRSA. When combined with SeNPs， PVP-I can enhance the bactericidal activity against SA and MRSA， but with better sensitizing effect on SA than MRSA and higher demand of iodine concentration （400 μg/mL） for sensitizing effect on MRSA. This study provides a theoretical basis for selecting optimal concentration and action time of the disinfectant， thus reducing SSI.