Micro Encapsulation and Characterization of Diclosulam in Xanthan Gum Based Polymeric System for Smart Delivery of Herbicide in Crop Production

Abstract

Aim: Micro encapsulation of diclosulam herbicide was done in xanthan gum based polymeric system through ionotropic gelation method to formulate a slow-release herbicide to achieve prolonged weed control in irrigated upland ecosystem. Place and Duration of Study: The slow-release formulation of diclosulam was synthesized and characterized in the Department of Nano Science & Technology, Tamil Nadu Agricultural University during January to July 2022. Methodology: Xanthan gum- alginate microsphere system was synthesized with varying concentrations of calcium chloride (CaCl2) (2, 4 and 6 per cent) to encapsulate diclosulam through ionotropic gelation. The size, entrapment efficiency, pore volume, pore radius, surface area and swelling behavior of microspheres were assessed to achieve higher loading of diclosulam and good stability of microspheres. Results: The mean diameter of xanthan gum-alginate microsphere was higher with 6 per cent ion gelation bath followed by the concentration of 4 and 2 per cent. Higher entrapment efficiency of diclosulam was achieved with loading of two percent diclosulam in six per cent calcium crosslinked microspheres. Conclusion: Xanthan gum-alginate microsphere system offers both burst release and controlled release of active ingredients. However, controlled release polymeric templates with herbicide will synchronize the release of herbicide with the emergence of weeds in the cropped situations for better weed management.