Peptide nucleic acid-clicked Ti <sub>3</sub> C <sub>2</sub> T <sub> <i>x</i> </sub> MXene for ultrasensitive enzyme-free electrochemical detection of microRNA biomarkers
Muhsin Ali, Erol Hasan, Sharat Chandra Barman, Mohamed Nejib Hedhili, Husam N. Alshareef, Dana Alsulaiman
Abstract
MXene nanosheets as a novel transducing material for amplification-free, nanoparticle-free, and isothermal electrochemical detection of microRNA biomarkers. Through bio-orthogonal copper-free click chemistry, azido-modified MXene nanosheets are covalently functionalized with clickable peptide nucleic acid probes targeting prostate cancer biomarker hsa-miR-141. The platform demonstrates a wide dynamic range, single-nucleotide specificity, and 40 aM detection limit outperforming more complex, amplification-based methods. Its versatility, analytical performance, and stability under serum exposure highlight the immense potential of this first example of click-conjugated MXene in the next generation of amplification-free biosensors.