Formulation of cartap hydrochloride crosslinked chitosan tripolyphosphate nanospheres and its characterization

Abstract

Insecticides are extensively applied in crop production and sometimes at higher concentration than their recommended doses, which has become an environmental hazard. Sustainable agricultural practices highlight minimal application of insecticides at low concentration. Use of controlled release formulations (CRFs) of pesticides in which active compound is associated with inert materials has emerged as an appealing alternative. In this study, nanospheres of insecticide cartap hydrochloride were developed using chitosan (CS) in the presence of tripolyphosphate (TPP) as crosslinker with the help of ionic gelation method, for the delivery of cartap hydrochloride. The nanoformulations were characterized by field emission scanning electron microscope (FESEM), X-ray diffraction (XRD), and Fourier transform infrared (FTIR) spectra. The FESEM images revealed that the size of chitosan tripolyphosphate (CS-TPP) nanospheres (nps) was in range of 117.01–185.27 nm, whereas cartap hydrochloride entrapped chitosan tripolyphosphate (C-CS-TPP) nanospheres had a size of 163.50–276.74 nm. FTIR results confirmed loading of cartap hydrochloride into chitosan tripolyphosphate nanospheres. The nanospheres showed encapsulation efficiency of 86.1% and were stable for 30 days at ambient temperature. In vitro release kinetics of insecticide from nanospheres followed a non Fickian diffusion mechanism. These nanospheres can act as slow-release formulation for the delivery of insecticide to the target organisms over a period of time, which is effective as well as environmentally safe.