Comparison of Faradaic and Non-Faradaic Impedance Biosensors Using 2-Electrode and 3-Electrode Configurations for the Determination of Bovine Serum Albumin (BSA)

• Published in: Analytical letters Vol. 57; no. 17; pp. 2959 - 2971
• Main Authors: Tran Nhu, Chi, Vu Quoc, Tuan, Do Quang, Loc, Nguyen Dang, Phu, Chun-Ping, Jen, Chu Duc, Trinh, Bui Thanh, Tung
• Format: Journal Article
• Language: English
• Published: Abingdon Taylor & Francis 21.11.2024; Taylor & Francis Ltd
• Subjects: Biosensor; Biosensors; bovine serum albumin (BSA); Cattle; Configuration management; electrochemical electrodes; Electrodes; immunosensor; Immunosensors; impedance spectroscopy; Microfluidic devices; Proteins; Sensitivity; Sensors; Serum albumin
• ISSN: 0003-2719; 1532-236X
• DOI: 10.1080/00032719.2024.2307464

This paper presents a study on the impedance spectroscopy methods applied to 2-electrode and 3-electrode biosensors. While 3-electrode electrochemical biosensors have been extensively studied and applied in various applications, the 2-electrode configuration of electrochemical biosensors still lacks comprehensive investigation for real-world applications. In particular, the miniaturization of the 3-electrode configuration for integration into microfluidic devices has been explored due to the relatively limited number of previous studies. A commercial screen-printed gold electrode was employed to develop immunosensors for bovine serum albumin (BSA) detection. The comparisons were performed on non-Faradaic and Faradic immunosensors corresponding to 2-electrode and 3-electrode configurations through impedance measurements. The results show the performance of both types of sensors in detecting BSA protein. While the 2-electrode configuration-based sensor can detect the BSA protein with a sensitivity of 12 Ω/µM, the 3-electrode configuration-based sensor shows superior results with a sensitivity of 7.2 kΩ/µM. Besides, the results also indicate that the 2-electrode configuration-based sensor can easily be miniaturized to integrate into a microfluidic channel to develop lab-on-a-chip systems. Although the 3-electrode configuration demonstrates advancements compared to the 2-electrode configuration, the 2-electrode system based on non-Faradaic processes still shows high potential for future applications.