加拿大麦克马斯特大学Leyla Soleymani团队利用便携式平台集成可编程DNA酶与电子读数，实现快速无培养细菌检测。相关研究成果于2021年6月24日发表在《自然—化学》。

目前细菌的检测和鉴定主要依靠细菌培养和核酸扩增等富集步骤来提高目标分析物的浓度。这些步骤增加了分析时间、成本和复杂性，使得很难实现真正快速的护理点检测。

该文报道了一种利用电活性RNA切割DNA酶（e-RCDs）鉴定特定细菌靶点并随后释放DNA条形码将信号转导到电子芯片上的电分析方法。将e-RCDs集成到具有纳米结构电极的双通道电子芯片中，提供了临床分析所需的分析灵敏度和特异性。e-RCD分析能够从含有多种非特异性细菌的面板中选择性地检测10CFU（相当于1000cfuml–1）的大肠杆菌。

与目前使用的培养基方法所需的几个小时相比，在分析时间不到1小时的情况下，对41例患者尿液样本进行的临床评估显示诊断敏感性为100%，特异性为78%。

附：英文原文

Title: Integrating programmable DNAzymes with electrical readout for rapid and culture-free bacterial detection using a handheld platform

Author: Richa Pandey, Dingran Chang, Marek Smieja, Todd Hoare, Yingfu Li, Leyla Soleymani

Issue&Volume: 2021-06-24

Abstract: The detection and identification of bacteria currently rely on enrichment steps such as bacterial culture and nucleic acid amplification to increase the concentration of target analytes. These steps increase assay time, cost and complexity, making it difficult to realize a truly rapid point-of-care test. Here we report the development of an electrical assay that uses electroactive RNA-cleaving DNAzymes (e-RCDs) to identify specific bacterial targets and subsequently release a DNA barcode for transducing a signal onto an electrical chip. Integrating e-RCDs into a two-channel electrical chip with nanostructured electrodes provides the analytical sensitivity and specificity needed for clinical analysis. The e-RCD assay is capable of detecting 10CFU (equivalent to 1,000CFUml–1) of Escherichia coli selectively from a panel containing multiple non-specific bacterial species. Clinical evaluation of this assay using 41 patient urine samples demonstrated a diagnostic sensitivity of 100% and specificity of 78% at an analysis time of less than one hour compared with the several hours needed for currently used culture-based methods.

DOI: 10.1038/s41557-021-00718-x

Source: https://www.nature.com/articles/s41557-021-00718-x