Microencapsulation of Zanthoxylum limonella oil (ZLO) in genipin crosslinked chitosan–gelatin complex for mosquito repellent application

Abstract Essential oil containing chitosan gelatin complex microcapsules crosslinked with genipin were prepared by complex coacervation process. The effects of various parameters such as oil loading, ratio of chitosan to gelatin, degree of crosslinking on oil content, encapsulation efficiency, and the release rate of the essential oil were studied. Scanning electron microscopy study indicated that the surface of the microcapsules were more irregular as the amount of oil loading increased. Thermal stability of microcapsules improved with the increase in the amount of chitosan in chitosan–gelatin matrix as revealed by thermogravimetric analysis. FT‐IR spectroscopy and differential scanning calorimetry study indicated that there was no significant interaction between chitosan–gelatin complex and oil. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2009