Rapid electrochemical dual-target biosensor composed of an Aptamer/MXene hybrid on Au microgap electrodes for cytokines detection

Rapid detection methods for cytokine storm markers, such as tumor necrosis factor alpha (TNF-alpha) and interferon gamma (IFN-gamma), are required. Herein, we describe the fabrication of a rapid electrochemical dual-target biosensor composed of aptamer/MXene (Ti3C2) nanosheet on an Au microgap electrode. Alternating current electrothermal flow (ACEF) significantly reduced the detection time (< 10 min) to achieve the rapid biosensor construction. Additionally, MXene nanosheet was synthesized to improve the detection sensitivity. A dual-type Au microgap electrode was designed to measure TNF-alpha and IFN-gamma levels using a single biosensor. Moreover, it performs 12 measurements using a small sample volume. To reduce detection time with stable aptamer-target complex formation, various ACEF conditions were evaluated and optimized to 10 min. Using the optimal conditions, the limit of detection (LOD) and selectivity were determined by electrochemical impedance spectroscopy (EIS). A linear region was observed in the concentration range of 1 pg/mL to 10 ng/mL of TNF-alpha and IFN-gamma. The LOD of TNF-alpha and IFN-gamma were 0.15 pg/mL and 0.12 pg/mL within 10 min, respectively. Furthermore, the proposed biosensor detected TNF-alpha and IFN-gamma diluted in 10% human serum in the concentration range of 1 pg/mL to 10 ng/mL with LODs of 0.25 pg/mL and 0.26 pg/mL, respectively.

Automated summary

In this study, a rapid electrochemical dual-target biosensor was fabricated for the detection of TNF-alpha and IFN-gamma. The biosensor constructed using aptamer/MXene nanosheet on an Au microgap electrode showed a short detection time (< 10 min) and improved sensitivity. The proposed biosensor also exhibited 12 measurements capability using a small sample volume.