Key Laboratory of Agricultural Information Acquisition Technology, Ministry of Agriculture and Rural Affairs, China Agricultural University, Beijing, 100083, China.
Department of Biological and Agricultural Engineering, University of Arkansas, Fayetteville, AR, 72701, USA.
Biosens Bioelectron. 2022 Nov 15;216:114653. doi: 10.1016/j.bios.2022.114653. Epub 2022 Aug 30.
An hourglass-mimicking biosensor was developed to detect target bacteria in 15 mL centrifugal tube using immune magnetic nanobeads to isolate the target from large-volume sample, gold@platinum nanozymes to label the target for amplification of biological signals, and a microplate reader/colorimetric card for determination of the target. First, a centrifugal tube with an iron ball framework was first coaxially assembled in the center of a Halbach ring magnet. After immune magnetic nanobeads, gold@platinum nanozymes and bacterial sample were mixed by repeated bottom-up of the tube using a stepper motor, nanobead-bacteria-nanozyme complexes were formed. Then, colorless HO-TMB was catalyzed by the nanozymes to produce blue TMBox. The color change was finally analyzed using the microplate reader or colorimetric card to determine bacterial concentration. This hourglass-mimicking biosensor could separate ∼95% targets from 10 mL bacteria sample and detect targets from 1.6 × 10 to 1.6 × 10 CFU/mL in 1.0 h with low detection limit of 16 CFU/mL.
一种沙漏模拟生物传感器被开发出来，用于在 15ml 离心管中检测目标细菌。该传感器使用免疫磁性纳米珠从大容量样品中分离目标物，使用金@铂纳米酶标记目标物以放大生物信号，并使用微孔板读数器/比色卡来确定目标物。首先，将具有铁球框架的离心管同轴组装在 Halbach 环形磁铁的中心。在免疫磁性纳米珠、金@铂纳米酶和细菌样本混合后，使用步进电机通过反复从底部向上移动离心管来混合，形成纳米珠-细菌-纳米酶复合物。然后，无色 HO-TMB 被纳米酶催化产生蓝色 TMBox。最后通过微孔板读数器或比色卡分析颜色变化，以确定细菌浓度。这种沙漏模拟生物传感器可以从 10ml 细菌样本中分离出约 95%的目标物，并在 1.0 小时内检测到 1.6×10 至 1.6×10 CFU/mL 的目标物，检测下限低至 16 CFU/mL。
