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Updated: Jun 2, 2026
Bacterial Detection & Identification Using Electrochemical Sensors
Published on: April 23, 2013
Multimeter voltage/electrochemiluminescence ratiometric biosensor integrating dual-function Fe-MOF and luminol-BNQD
Wenzhuo Wang1, Wei Yuan2, Zhilan Sun3
1College of Food Science, Northeast Agricultural University, Harbin, 150030, PR China; Jiangsu Key Laboratory for Food Quality and Safety-State Key Laboratory Cultivation Base, Ministry of Science and Technology, Nanjing, 210014, PR China; Institute of Agricultural Products Processing, Jiangsu Academy of Agricultural Sciences, Nanjing, 210014, PR China.
Background:
Acinetobacter baumannii threatens food safety due to its harsh-condition survival, driving the need for portable, accurate detection. Electrochemiluminescence-based closed bipolar electrode (ECL-BPE) biosensors are attractive for their simplicity and miniaturization, but conventional designs rely solely on a single anodic ECL signal. This single-signal strategy suffers from poor anti-interference ability, limiting detection accuracy.
Results:
We first developed a dual-signal ratiometric biosensor integrating multimeter voltage and ECL readouts for A. baumannii detection. A dual-functional MOF with DNA immobilization capability and capacitance-like activity was designed to anchor DNA and generate a cathode voltage signal readable by a multimeter. Meanwhile, boron nitride quantum dots (BNQDs) served as a novel co-reactant to establish a luminol-based ECL system, producing an anodic ECL signal captured by a smartphone. Upon target recognition, the increased cathode interfacial resistance allocated a larger voltage to the cathode, enhancing capacitive deposition and yielding a higher multimeter signal, while reducing the anode voltage and thus suppressing the anodic ECL intensity. This inverse correlation between the two signals and target concentration enabled a ratiometric biosensor with significantly improved accuracy, achieving a detection limit of 3.5 CFU g-1, along with high stability, specificity, and anti-interference ability. The biosensor showed 100% concordance with q-PCR results when tested on 12 real samples and 8 positive controls.
Significance:
This work presents a dual-signal ratiometric biosensor on BPE platform and provides a portable, accurate platform for pathogen detection in food industry.
