Effect of Physicochemical Properties in Water on Release Profile of Metominostrobin from Time-Controlled Release Granule

Development of Time-Controlled Release Granule Containing Metominostrobin (Part 5)

Abstract

The effect of pH, water hardness and temperature in water on release profile of time-controlled release granule (TCRG) was investigated. The release profile of metominostrobin from TCRG did not change regardless of changing pH from 4 to 10 and water hardness from 3 to 100. However, as the temperature increased, the lag time was shortened and the release rate became faster. When the logarithmic cumulative temperature was plotted as abscissa and release percentage as ordinate, the release profiles measured at fixed temperatures (15, 20, 25, 30°C) and changing temperatures from 15 to 30°C periodically were superposed. Therefore, the released percentage could be predicted from cumulative temperature. Thus, it was thought that the difference in water permeation through PVC membrane by temperature caused different release profiles.