Application of Renewable Kenaf Cellulose Nanofiber as a Temephos Nanocarrier for Control of Aedes Aegypti (Diptera: Culicidae) Larvae

Abstract Larviciding is an effective control method in managing mosquito-borne diseases. However, current carrier materials used in larvicides formulation raised environmental concerns due to its non-renewable origin. Herein, our study aimed to evaluate the application of the renewable source kenaf cellulose nanofiber (KCNF) impregnated with temephos for the control of Aedes aegypti mosquito larvae. The morphology of KCNF+T was examined using field emission scanning electron microscope (FESEM) and transmission electron microscopy (TEM) while the quantity of temephos impregnated, released, and retained on the fibers upon dispersion in water were determined using high performance liquid chromatography (HPLC). Subsequently, the bioefficacy of the KCNF+T was evaluated against Ae. aegypti larvae. The FESEM and TEM micrograph verified the presence of temephos on the KCNF after the impregnation. HPLC analysis showed the amount of temephos impregnated on KCNF was 97 % of the 0.1 mg temephos. Upon dispersion in water, KCNF+T released 53% temephos and the retention of temephos on KCNF+T gradually decreased to 30, 17 and 7 % on the first, third and fifth month, respectively. The exposure of Ae. aegypti larvae to KCNF+T at concentration 0.006 to 0.01 mg/L was effective at 17 - 25 folds in killing Ae. aegypti larvae compared to temephos without KCNF. Microscopy examination revealed accumulation of the KCNF on the larval appendages. Overall, our study demonstrated that KCNF made from renewable source is an effective nanocarrier of temephos for the control of Ae. aegypti mosquito larvae.