Related Experiment Video
Updated: Jun 26, 2026

Detection of Bacteria Using Fluorogenic DNAzymes
Published on: May 28, 2012
A dual-responsive fluorescence aptasensor for simultaneous detection of antibiotics and construction of molecular
Junbo Hu1, Haonan Xu1, Pengfei Sun1
1The State Key Laboratory of Flexible Electronics (LoFE) & Jiangsu Key Laboratory for Biosensors, Institute of Advanced Materials (IAM), Nanjing University of Posts & Telecommunications, 9 Wenyuan Road, Nanjing 210023, China. iamxfliu@njupt.edu.cn.
Abstract:
The large-scale use of antibiotics in agriculture and husbandry has become a serious threat to the public health and environment. There is an urgent need to develop versatile sensing systems capable of detecting multiple antibiotics in animal-derived food. In this work, a dual-responsive fluorescence aptasensor was established for simultaneous detection of kanamycin (Kana) and tobramycin (Tob). Two different DNA probes were designed to specially bind to Kana and Tob, each producing a fluorescence signal of different color. The biosensor is simple, rapid, highly specific and sensitive for detecting Kana and Tob in milk, with detection limits of 97 nM and 210 nM, respectively. Three molecular logic gates were constructed using antibiotics as inputs, allowing for intelligent detection of antibiotics through different logic operations. This convenient, practical, and low cost biosensor provides a versatile platform for simultaneous detection of multiple targets in animal-derived foods, particularly in resource-limited regions.
Related Concept Videos
Enzyme-Linked Immunosorbent Assay
There are many different types of ELISAs, but they all involve an antibody molecule whose constant region binds an enzyme, leaving the variable region free to bind its specific antigen. Enzyme-substrate reaction allows the antigen to be visualized or quantified.
Microbial Biosensors
Automated Microbial Diagnostics

