Development of controlled release formulations of thiabendazole

Abstract

This study aimed to develop controlled release formulation of Thiabendazole for reduced contaminations to soil water and agricultural produces. The idea behind this work was based on changing the ionization status of Thiabendazole molecule throughout pH changes to become a cation then adsorbing it to bentonite clay surfaces. Equilibrium concentrations of Thiabendazole in the adsorption solutions were determined by HPLC. Results showed that Thiabendazole was better adsorbed in clay at the lowest pH value (pH 3). Furthermore, raising the temperature of the adsorption reaction increased the adsorbed amount of Thiabendazole. Release experiments showed that Thiabendazole is extremely slower at pH 3 than at pH 5.5 or pH 9. These promising results suggest that application of Thiabendazole clay based formulation may reduce the applied rate and that the released fraction consequently may reduce the environmental contamination. It is also advantageous to use these formulations in the acidic soil for plant disease control.