Label-free Electrochemical Immunosensor Toward IGFBP-7 Biomarker for Early Monitoring of Acute Kidney Injury
9
Issued Date
2026-01-01
Resource Type
ISSN
1530437X
eISSN
15581748
Scopus ID
2-s2.0-105032879938
Journal Title
IEEE Sensors Journal
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SCOPUS
Bibliographic Citation
IEEE Sensors Journal (2026)
Suggested Citation
Unson S., Ruankham W., Phopin K., Tantimongcolwat T. Label-free Electrochemical Immunosensor Toward IGFBP-7 Biomarker for Early Monitoring of Acute Kidney Injury. IEEE Sensors Journal (2026). doi:10.1109/JSEN.2026.3671274 Retrieved from: https://repository.li.mahidol.ac.th/handle/123456789/115838
Title
Label-free Electrochemical Immunosensor Toward IGFBP-7 Biomarker for Early Monitoring of Acute Kidney Injury
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Abstract
Insulin-like growth factor-binding protein 7 (IGFBP-7) is a potential biomarker for early diagnosis of acute kidney injury (AKI). Herein, we have developed a novel label-free electrochemical immunosensor based on the self-assembly of 6-(ferrocenyl)hexanethiol (Fc) and antibody-coupled L-cysteine on the gold nanoparticle-modified electrode (Ab/Fc-Au/SPCE) for sensitive detection of IGFBP-7 in urine. Fc was directly embedded on the electrode surface to serve as an intrinsic redox signal for the IGFBP-7 immunosensor. The binding of IGFBP-7 target to the immobilized antibody resulted in a decrease in the peak current of the differential pulse voltammetry (DPV) measurement. The Ab/Fc-Au/SPCE exhibited a good linear DPV response to IGFBP-7 concentrations ranging from 0.0001 to 100.0 pg mL<sup>-1</sup>, with a limit of detection (LOD) of 0.07 pg mL<sup>-1</sup>. Validation using spiked artificial urines showed recovery rates in a range of 79.8 to 109.3%. The proposed immunosensor demonstrated good specificity and long-term stability, which are crucial properties for biosensor implementation. Importantly, the electrochemical IGFBP-7 immunosensor can function without the need for external redox agents, requiring only simple steps of sample incubation and subsequent PBS buffer rinsing. Our findings demonstrate a promising potential of Ab/Fc-Au/SPCE immunosensor as a Point-of-Care Testing (POCT) device for rapid detection of IGFBP-7 in early AKI diagnosis.