Enhanced Electrochemical Biosensing of the Sp17 Cancer Biomarker in Serum Samples via Engineered Two-Dimensional MoS2 Nanosheets on the Reduced Graphene Oxide Interface

Amit K Yadav; Damini Verma; Pratima R Solanki

doi:10.1021/acsabm.3c00464

Enhanced Electrochemical Biosensing of the Sp17 Cancer Biomarker in Serum Samples via Engineered Two-Dimensional MoS₂ Nanosheets on the Reduced Graphene Oxide Interface

ACS Appl Bio Mater. 2023 Oct 16;6(10):4250-4268. doi: 10.1021/acsabm.3c00464. Epub 2023 Sep 16.

Authors

Amit K Yadav¹, Damini Verma¹, Pratima R Solanki¹

Affiliation

¹ Nano-Bio Laboratory, Special Centre for Nanoscience, Jawaharlal Nehru University, New Delhi 110067, India.

PMID: 37715717
DOI: 10.1021/acsabm.3c00464

Abstract

In the present investigation, we reported a label-free and highly effective immunosensor for the first time employing a nanostructured molybdenum disulfide nanosheets@reduced graphene oxide (nMoS₂ NS@rGO) nanohybrid interface for the determination of sperm protein 17 (Sp17), an emerging cancer biomarker. We synthesized the nMoS₂ NS@rGO nanohybrid using a one-step hydrothermal technique and then functionalized it with 3-aminopropyltriethoxysilane (APTES). Furthermore, the anti-Sp17 monoclonal antibodies were covalently attached to the APTES/nMoS₂ NS@rGO/indium tin oxide (ITO) electrode utilizing 1-ethyl-3-(3-dimethylaminopropyl)carbodiimide-N-hydroxy succinimide (EDC-NHS) coupling chemistry. Bovine serum albumin (BSA) was then used to block nonspecific binding regions on the anti-Sp17/APTES/nMoS₂ NS@rGO/ITO bioelectrode. The morphological and structural features of the synthesized nanohybrid and the modified electrodes were studied using transmission electron microscopy, scanning electron microscopy with energy dispersive X-ray (EDX) composition studies, atomic force microscopy, Fourier transform infrared spectroscopy, and Raman spectroscopy. The immunoreaction between the Sp17 antigen and anti-Sp17 antibodies on the surface of the BSA/anti-Sp17/APTES/nMoS₂ NS@rGO/ITO sensing bioelectrode was applied as the basis for the detection technique, which measured the electrocatalytic current and impedimetric response change. The designed BSA/anti-Sp17/APTES/nMoS₂ NS@rGO/ITO bioelectrode showed improved amperometric and impedimetric biosensing performance in the response studies, including remarkable sensitivity (23.2 μA ng^-1mL cm^-2 and 0.48 kΩ mL ng^-1 cm^-2), wider linearity (0.05-8 and 1-8 ng mL^-1), an excellent lower detection limit (0.13 and 0.23 ng mL^-1), and a rapid response time of 20 min. The biosensor exhibited impressive storage durability lasting 7 weeks and showed remarkable precision in identifying Sp17 in serum samples from cancer patients, as confirmed using the enzyme-linked immunosorbent assay method.

Keywords: cancer; electrochemistry; molybdenum disulfide; nanohybrid; nanosheets; reduced graphene oxide; sperm protein 17.