Department of Chemistry, Pukyong National University, Busan 48513, Republic of Korea.
Department of Chemical Engineering and Materials Research Institute, Pennsylvania State University, University Park, PA 16802, USA.
Biosensors (Basel). 2024 Jan 11;14(1):37. doi: 10.3390/bios14010037.
In this study, we developed a multi-walled carbon nanotube (MWCNT)-based field-effect transistor (MWCNT-FET) sensor with high sensitivity and selectivity for microcystin-LR (MC-LR). Carboxylated MWCNTs were activated with an MC-LR-targeting aptamer (MCTA). Subsequently the bioactivated MWCNTs were immobilized between interdigitated drain (D) and source (S) electrodes through self-assembly. The top-gated MWCNT-FET sensor was configured by dropping the sample solution onto the D and S electrodes and immersing a Ag/AgCl electrode in the sample solution as a gate (G) electrode. We believe that the FET sensor's conduction path arises from the interplay between the MCTAs, with the applied gate potential modulating this path. Using standard instruments and a personal computer, the sensor's response was detected in real-time within a 10 min time frame. This label-free FET sensor demonstrated an impressive detection capability for MC-LR in the concentration range of 0.1-0.5 ng/mL, exhibiting a lower detection limit of 0.11 ng/mL. Additionally, the MWCNT-FET sensor displayed consistent reproducibility, a robust selectivity for MC-LR over its congeners, and minimal matrix interferences. Given these attributes, this easily mass-producible FET sensor is a promising tool for rapid, straightforward, and sensitive MC-LR detection in freshwater environments.
在本研究中,我们开发了一种基于多壁碳纳米管(MWCNT)的场效应晶体管(MWCNT-FET)传感器,该传感器对微囊藻毒素-LR(MC-LR)具有高灵敏度和选择性。羧基化的 MWCNT 与针对 MC-LR 的适体(MCTA)激活。随后,通过自组装将生物激活的 MWCNT 固定在叉指漏极(D)和源极(S)电极之间。通过将样品溶液滴加到 D 和 S 电极上,并将 Ag/AgCl 电极浸入样品溶液中作为栅极(G)电极,配置顶栅 MWCNT-FET 传感器。我们相信,FET 传感器的传导路径源自 MCTAs 的相互作用,施加的栅极电势调节此路径。使用标准仪器和个人计算机,在 10 分钟的时间内实时检测传感器的响应。这种无标记的 FET 传感器在 0.1-0.5 ng/mL 的浓度范围内对 MC-LR 表现出令人印象深刻的检测能力,检测限低至 0.11 ng/mL。此外,MWCNT-FET 传感器表现出一致的重现性、对 MC-LR 与其同系物的稳健选择性以及最小的基质干扰。鉴于这些特性,这种易于大规模生产的 FET 传感器是一种很有前途的工具,可用于快速、直接、灵敏地检测淡水环境中的 MC-LR。