DOI: 10.1002/app.71060 ISSN: 0021-8995
Dual Enzyme‐ and pH‐Responsive Polydopamine‐Modified Poly(
l
‐Lactic Acid) Nanocarrier for Controlled Release of Indoxacarb Against
Zeugodacus tau
Kirna Devi, Sunil Kumar, Alka Rana, Rajender Kumar ABSTRACT
Recent advancements in material engineering have enabled the development of multi‐stimulus responsive release systems constructed from biodegradable polymers for sustainable pest management. In the present study, a dual enzyme‐ and pH‐responsive polydopamine‐modified poly(
l
‐lactic acid) (PDL) nanocomposite was developed for controlled release of indoxacarb (IN). The functionalized and encapsulated carriers were characterized using UV–visible spectroscopy, Fourier‐transform infrared (FTIR), thermogravimetric analysis (TGA), zeta potential, field emission scanning electron microscopy (FE‐SEM), and x‐ray photoelectron spectroscopy (XPS). The integrated matrix demonstrated pH‐responsiveness derived from polydopamine (PDA) and enzyme‐responsiveness attributed to the ester linkage of poly (
l
‐lactic acid) (PLA), which undergoes lipase‐catalyzed hydrolysis. The maximum cumulative release was achieved under neutral pH and enzymatic conditions, which was further accelerated with temperature. Kinetic modeling revealed that Fickian diffusion governed the release process, while best fitting of the diffusion‐erosion model indicates that polymeric degradation played a significant role in sustained release. The nanoformulation also effectively protected IN from UV‐induced degradation due to UV shielding of PDA. Moreover, IN@PDL exhibited high insecticidal efficiency against
Zeugodacus tau
. Thus, this synergistic multi‐stimulus responsive formulation offers an efficient and environmentally benign strategy for controlled pesticide delivery.