Natural oxidation of Ti3C2Tx to construct efficient TiO2/Ti3C2Tx photoactive heterojunctions for advanced photoelectrochemical biosensing of folate-expressing cancer cells

Razium A Soomro; Jai Kumar; Rana R Neiber; Sirajuddin; Amerah M Alotaibi; Shoyebmohamad F Shaikh; Nazeer Ahmed; Ayman Nafady

doi:10.1016/j.aca.2023.341016

Natural oxidation of Ti₃C₂T_x to construct efficient TiO₂/Ti₃C₂T_x photoactive heterojunctions for advanced photoelectrochemical biosensing of folate-expressing cancer cells

Anal Chim Acta. 2023 Apr 22:1251:341016. doi: 10.1016/j.aca.2023.341016. Epub 2023 Feb 27.

Authors

Razium A Soomro¹, Jai Kumar², Rana R Neiber³, Sirajuddin⁴, Amerah M Alotaibi⁵, Shoyebmohamad F Shaikh⁵, Nazeer Ahmed⁶, Ayman Nafady⁷

Affiliations

¹ State Key Laboratory of Organic-Inorganic Composites, Beijing Key Laboratory of Electrochemical Process and Technology for Materials, Beijing University of Chemical Technology, Beijing, 100029, China.
² College of Chemical Engineering, University of Chinese Academy of Sciences, 19 A Yuquan Road, Beijing, 100049, China.
³ College of Chemical Engineering, University of Chinese Academy of Sciences, 19 A Yuquan Road, Beijing, 100049, China; Beijing Key Laboratory of Ionic Liquids Clean Process, CAS Key Laboratory of Green, Process, and Engineering, Institute of Process Engineering, Chinese Academy of Sciences, 100190, Beijing, China.
⁴ ICCBS, HEJ, University of Karachi, Karachi, 75270, Pakistan.
⁵ Department of Chemistry, College of Science, King Saud University, Riyadh, 11451, Saudi Arabia.
⁶ Sapienza University of Rome, Research Center on Nanotechnology Applied to Engineering, Rome, Italy.
⁷ Department of Chemistry, College of Science, King Saud University, Riyadh, 11451, Saudi Arabia. Electronic address: anafady@ksu.edu.sa.

PMID: 36925274
DOI: 10.1016/j.aca.2023.341016

Abstract

The rapid-charge carrier recombination and low conductivity are critical in devising an efficient photoelectrochemical (PEC) sensor. Herein, we propose partial oxidation of few-layered MXene (Ti₃C₂T_x) to construct a photo-active TiO₂/Ti₃C₂T_x platform that could be configured for PEC sensing of folate receptors (FR), particularly, FR-expressing breast cancer cells (MDA-MB-231). MXene-Ti₃C₂T_x dispersion was oxidized in natural-open air conditions, where continuous exposure for six (06) days allowed for homogeneous in-situ growth of TiO₂ over MXenes nanosheets (MX-06). This exposure enabled partial oxidation of MXene-sheets with a balanced TiO₂ to MXene content that could exhibit improved photoresponsive characteristics owing to the synergism of redox-active TiO₂ and highly conductive underlying Ti₃C₂T_x. The photoelectrode was then adapted for biorecognition by conjugating chitosan and folic acid (FA) networks, which permitted selective detection of FR-expressed cells with significant antifouling capabilities against common proteins such as bovine serum album (BSA), hemoglobin, and immunoglobulin G. (Ig G). The detection mechanism relies on FA's strong affinity for cancer cell folate receptors, which proportionally inhibited the photoelectrodes PEC oxidation response to ascorbic acid (AA)(mediator). The proposed inhibition strategy enabled sensitive detection of FR-expressed MDA-MB-231 cells in the concentration range of 1 × 10² to 2 × 10⁷ cells/mL with a detection limit of 1.01 cells/mL (S/N = 3).

Keywords: Cancer biomarkers; MXenes; Photoactive heterojunction; Photoelectrochemical biosensors; TiO(2)/Ti(3)C(2)T(x).

MeSH terms

Folic Acid
Neoplasms*
Oxidation-Reduction
Titanium*

Substances

titanium dioxide
MXene
Titanium
Folic Acid