The invention provides a method of obtaining a reusable charge- transfer(CT) based agrogel. The method includes selecting a first gelator (S)-methyl 2-(4-(pyren-1-yl)butanamido)-3-(1H- imidazol-4-yl)propanoate and a second gelator 2,4,7- trinitrofluorenone. At least one semiochemical is added to the first and the second gelator to obtain a mixture. Subsequent to obtaining mixture, the mixture is subjected to at least one cycle of heating and cooling to obtain a charge transfer (CT) based agrogel. The charge transfer gel thus obtained is reusable and has ability for a sustained release of the semiochemical by retaining the active agent for an extended period of time. The invention also provides a device for controlling pests.
