Preparation and characterization of chloridazon-loaded alginate/chitosan nanocapsules

In addition to the detrimental environmental effects of herbicides, including the pollution of soil, atmosphere, groundwater aquifers and run-off water, the lack of caution and direct or indirect exposure to these products can cause short-term and long-term human health effects. However, nanotechnology, with its many applications, can be very helpful in improving agriculture and reducing the side effects of chemicals used in agriculture. Nano-encapsulation of chemicals used in agriculture is one of the strategies to improve precision agriculture. Nano-encapsulated herbicides are controlled membrane systems in which the active ingredient is coated with semi-permeable membranes, which may be organic or inorganic polymers. In our study, chloridazon herbicide was selected as the active ingredient for Nano-encapsulation. Like many other agricultural herbicides, the major problem with this herbicide is environmental pollution and its adverse health effects. The ionic gelation method was used to synthesize nanocapsules consisting of alginate and chitosan for chloridazon encapsulation. Alginate-chitosan nanoparticles were prepared in a two-step process involving the ionotropic pre-gelation of an alginate core and then the formation of a chitosan polyelectrolyte complex. The alginate-chitosan nanocapsules containing chloridazon were synthesized at a size of 253 nm with a polydispersity index (PDI) of 0.266 and a zeta potential of -1.43 mV. The loading capacity and entrapment efficiency of these nanocapsules were 14% and 57%, respectively. The study of chloridazon release from formulated alginate-chitosan nanocapsules was performed using dialysis tube testing and UV spectroscopy. The results of our study showed controlled release of chloridazon from loaded alginate-chitosan nanocapsules. In general, alginate-chitosan nanocapsules as a Nano-carrier, have the potential to become a commercial formulation for chloridazon encapsulation. On the other hand, controlled release and increasing the duration of action of chloridazon, along with reducing the required dose, is promising in reducing the adverse health and environmental effects caused by chloridazon and improving precision agriculture.