Selection of a DNA aptamer for the development of fluorescent aptasensor for carbaryl detection

An improved ssDNA library immobilized systematic evolution of ligands by enrichment (SELEX) was applied to select aptamers against carbaryl. After nine selection rounds, a highly enriched ssDNA pool was obtained. The Apta3 was demonstrated as the optimal aptamer. In order to facilitate the modification of aptamer, the Apta3 was further truncated with the dissociation constant (K-d) of 0.364 +/- 0.055 mu mol/L and a fluorescent aptasensor was developed. The linear range for carbaryl was from 100 nmol/L to 1500 nmol/L, with the limit of detection was as low as 15.23 nmol/L. Besides, the biosensor was validated for the carbaryl spiked real samples, and the recoveries were between 97.7% and 107.3%. (C) 2021 Chinese Chemical Society and Institute of Materia Medica, Chinese Academy of Medical Sciences. Published by Elsevier B.V. All rights reserved.

Automated summary

An improved ssDNA library immobilized SELEX method was used to select aptamers for carbaryl, resulting in the identification of Apta3 as the optimal aptamer. A fluorescent aptasensor with a low detection limit for carbaryl was developed successfully and validated with real samples, showing good recoveries.