Binary transition metal oxide modified laser-scribed graphene electrochemical aptasensor for the accurate and sensitive screening of acute myocardial infarction

Abstract
Laser-scribed graphene (LSG) electrodes have gained significant interest due to the ease in fabrication, surface modification, and potential to develop various types of electrochemical sensors and biosensors. In these studies, a new type of zinc ferrite nanoparticles (ZnFe2O4 NPs) modified LSG electrochemical sensing system comprising LSG-ZnFe2O4 working electrode, LSG reference, and LSG counter electrode on a single polyimide substrate is presented. LSG-ZnFe2O4 electrodes are fabricated by drop-casting a solution of ZnFe2O4 NPs onto the LSG electrode, which gave a 31% enhancement of sensitivity and electrocatalytic activity compared to the bare LSG electrode. LSG-ZnFe2O4 electrochemical aptasensor for acute myocardial infarction (AMI) screening is developed by detecting the cardiac Troponin-I (cTn-I) biomarker. The results show that the developed aptasensor could detect a broad concentration range of cTn-I with a limit of detection of 0.001 ng/mL and a sensitivity of 19.32 (±0.25) µA/(ng/mL). In addition to this, LSG-ZnFe2O4-aptasensor shows higher selectivity towards the detection of cTn-I and negligible cross-reactivity with other interfering biomolecules. Finally, it is demonstrated that LSG-ZnFe2O4-aptasensor can easily detect different concentrations of cTn-I spiked in human serum samples. These results show that the LSG-ZnFe2O4-aptasensor is a promising diagnostic tool to monitor cTn-I and could be a potential candidate to develop point-of-care devices for cTn-I biomarker detection and various other disease biomarkers in the future.

Citation
Rauf, S., Mani, V., Lahcen, A. A., Yuvaraja, S., Beduk, T., & Salama, K. N. (2021). Binary transition metal oxide modified laser-scribed graphene electrochemical aptasensor for the accurate and sensitive screening of acute myocardial infarction. Electrochimica Acta, 138489. doi:10.1016/j.electacta.2021.138489

Acknowledgements
The authors would like to express their acknowledgments to the financial support of funding from King Abdullah University of Science and Technology (KAUST), Saudi Arabia. Also, we thank the KAUST Sensor Initiative for supporting this work. In addition, we would like to thank Dr. Govindasamy Mani for his valuable suggestions regarding material synthesis.

Publisher
Elsevier BV

Journal
Electrochimica Acta

DOI
10.1016/j.electacta.2021.138489

Additional Links
https://linkinghub.elsevier.com/retrieve/pii/S0013468621007799

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