Affiliations 

  • 1 Advanced Medical and Dental Insitute, University Sains Malaysia, Bertam 13200, Kepala Batas, Pulau Pinang, Malaysia
  • 2 Faculty of Medicine, University Malaya, 50603 Kuala Lumpur, Malaysia
  • 3 Vector Control Research Unit (VCRU), School of Biological Sciences, University Sains Malaysia, 11800 Gelugor, Pulau Pinang, Malaysia
Trop Biomed, 2021 Sep 01;38(3):453-461.
PMID: 34608119 DOI: 10.47665/tb.38.3.088

Abstract

Larviciding is an effective control method in managing mosquito-borne diseases. However, most of the current larvicide formulations have raised environmental concerns due to the presence of non-biodegradable inert or carrier materials. Therefore, the utilisation of biodegradable natural cellulosic fibres has created much attention. This study aims to evaluate the application of biodegradable kenaf cellulose nanofibre (KCNF) in larvicide formulation where the larvicide, namely temephos, is impregnated onto the fibre matrix (KCNF+T). The bioefficacy of the formulation was evaluated against Aedes aegypti ( A. aegypti) mosquito larvae. The presence of the temephos on the KCNF was evaluated through micro- morphological analysis using a field emission scanning electron microscope (FESEM) and a transmission electron microscope (TEM), while the quantity of temephos impregnated, released, and retained on the fibres upon dispersion in water were determined using high performance liquid chromatography (HPLC). It was observed that 97% of the temephos (0.1 mg) were impregnated on the KCNF. Upon dispersion in water, 53% of the temephos were released from the KCNF+T and the retention of temephos on the KCNF+T gradually decreased to 30%, 17%, and 7% on the first, third, and fifth month, respectively. Exposure of the A. aegypti larvae to the KCNF+T at concentrations ranging between 0.006 to 0.01 mg/L was effective in killing A. aegypti larvae at 17-25 folds as compared to using the temephos without KCNF. Microscopic examination revealed the accumulation of the KCNF on the larval appendages. In conclusion, this study demonstrated that the utilisation of KCNF in pesticide formulation is an effective way of delivering the temephos to control A. aegypti mosquito larva.

* Title and MeSH Headings from MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.