抄録
This study was designed to estimate the difference in the stability and the antibacterial activity between PVP-ISU and U-pasta®, (UP) of Povidone-iodine sugar ointments which were prepared in our hospital and manufactured in a company. Observed were the changes in these two preparations which were preserved throughout the experimental period of 7, 30 and 60 days and at the temperatures of 20 and 40°C. The stability of each sample was investigated on pH value, available iodine, and sugar quantity. The bacteria tested were six strains of two strains each of MRSA, P. aeruginosa and P. mirabilis isolated from the decubitus of patients.
In PVP-ISU maintained for 30 days at 40°C, the findings revealed that pH value dropped from 4.0 to 2.9 and the concentrations of available iodine and sugar decreased to 74.7% and 41.1% respectively. When storing up to 60 days at 40°C, the pH value lowered to 2.7, the dissolution of sugar was remarkably witnessed, and the concentration of available iodine was recognized as being only 11%. However, all of the strains tested were killed within 10 min. On the other hand, in UP sustained for 60 days at 40°C, no remarkable changes were observed except for a slight change in the pH value (4.7→4.0).
These results suggest that PVP-ISU, in which the stabilizing agents are not contained, cannot be used for an extended time because it cannot maintain the proper stability of pH, sugar and available iodine at a high temperature (40°C). However, UP may possibly be used safely longer than 60 days even if it were stored at a high temperature (40°C).
