Rapid detection of carcinoembryonic antigen by means of an electrochemical aptasensor

Nigara Yunussova; Meruyert Tilegen; Tri Thanh Pham; Damira Kanayeva

doi:10.1016/j.isci.2024.109637

Rapid detection of carcinoembryonic antigen by means of an electrochemical aptasensor

iScience. 2024 Mar 28;27(5):109637. doi: 10.1016/j.isci.2024.109637. eCollection 2024 May 17.

Authors

Nigara Yunussova¹, Meruyert Tilegen², Tri Thanh Pham³, Damira Kanayeva³

Affiliations

¹ Ph.D. program in Life Sciences, Department of Biology, School of Sciences and Humanities, Nazarbayev University, 53 Kabanbay batyr Avenue, Astana 010000, Kazakhstan.
² M.Sc. program in Molecular Medicine, School of Medicine, Nazarbayev University, 5/1 Kerey-Zhanibek Khandar St, Astana 010000, Kazakhstan.
³ Department of Biology, School of Sciences and Humanities, Nazarbayev University, 53 Kabanbay batyr Avenue, Astana 010000, Kazakhstan.

Abstract

Carcinoembryonic antigen (CEA) is a critical biomarker for identifying colon cancer. This work presents an electrochemical impedance spectroscopy (EIS) based aptasensor for detecting CEA, utilizing a single-stranded DNA (ssDNA) aptamer previously selected and characterized by our research group. The surface of an interdigitated gold electrode (IDE) was successfully functionalized with an 18-HEG-modified aptamer sequence. The developed aptasensor demonstrated high specificity and sensitivity with detection limits of 2.4 pg/mL and 3.8 pg/mL for CEA in buffer and human serum samples, respectively. The optimal incubation time for the target protein was 20 min, and EIS measurements took less than 3 min. Atomic force microscopy (AFM) micrographs supported the EIS data, demonstrating a change in IDE surface roughness after each modification step, confirming the successful capture of the target. The potential of this developed EIS aptasensor in detecting CEA in complex samples holds promise.

Keywords: Applied sciences; Bio-electrochemistry; Sensor system.