Simultaneous Amperometric Aptasensor Based on Diazonium Grafted Screen-Printed Carbon Electrode for Detection of CFP10 and MPT64 Biomarkers for Early Tuberculosis Diagnosis

Abstract

Early diagnosis is highly crucial for life-saving and transmission management of tuberculosis (TB). Despite the low sensitivity and time-consuming issues, TB antigen detection still relies on conventional smear microscopy and culture techniques. To address this limitation, we report the development of the first amperometric dual aptasensor for the simultaneous detection of Mycobacterium tuberculosis secreted antigens CFP10 and MPT64 for better diagnosis and control of TB. The developed sensor was based on the aptamers–antibodies sandwich assay and detected by chronoamperometry through the electrocatalytic reaction between peroxidase-conjugated antibodies, H2O2, and hydroquinone. The CFP10 and MPT64 aptamers were immobilized via carbodiimide covalent chemistry over the disposable dual screen-printed carbon electrodes modified with a 4-carboxyphenyl diazonium salt. Under optimized conditions, the aptasensor achieved a detection limit of 1.68 ng mL−1 and 1.82 ng mL−1 for CFP10 and MPT64 antigens, respectively. The developed assay requires a small sample amount (5 µL) and can be easily performed within 2.5 h. Finally, the dual aptasensor was successfully applied to clinical sputum samples with the obtained diagnostic sensitivity (n = 24) and specificity (n = 13) of 100%, respectively, suggesting the readiness of the developed assay to be used for TB clinical application.

Aptamer-based rapid diagnosis for point-of-care application

“…This amperometric cTnI aptasensor performed admirably, with a wide linear range of 100–0.01 pg mL1 and a detection limit of 1.24 103 pg mL1 (S/N = 3), good selectivity, satisfying reproducibility, exceptional stability, and good recovery(Chen et al 2022 ). (Yunus et al 2022 ) used amperometric aptasensor based on diazonium grafted screen-printed carbon electrode for detecting cfp10 and mpt64 biomarkers for early tuberculosis diagnosis with a detection limit of 1.68 ng mL − 1 and 1.82 ng mL − 1 for CFP10 and MPT64 antigens, respectively. Petroni et al developed a simple method for the amperometric detection of nitrite and ascorbate using a ME device with screen-printed electrodes (Petroni et al 2017 ) [100], whereas a systematic study of the prolonged amperometric detection of oxygen in ILs was achieved by using mechanical polishing to activate platinum screen-printed electrodes (Pt-SPEs) (Lee et al 2016 ).…”

Utilizing Electrochemical Biosensors as an Innovative Platform for the Rapid and On-Site Detection of Animal Viruses

“…Because the low-cost manufacturing technology of SPEs can be easily extended to mass production and all types of materials can be added to screen-printing slurry, SPEs can be customized for different substrate materials, shapes, and sizes in production to meet the needs of a variety of research. At the same time, SPEs are small, powerful, low-cost, and maintenance-free and have been widely used in electrochemical research in environmental monitoring [98][99][100], clinical diagnoses [101,102], drug analyses [103], and food detection [97,104,105], which has promoted the development of electrochemical biosensors. The wide application of nanomaterials is also the cause of the rapid development of electrochemical sensors.…”