Label-free and ultra-low concentration detection of gastric cancer biomarker miRNA 106a using In-Sn-Zn-O thin-film transistor biosensor

Gastric cancer remains a leading cause of morbidity and mortality globally. Early screening is essential for improving survival rates. This study proposes an approach to early gastric cancer screening utilizing indium-tin-zinc-oxide (ITZO) thin-film transistors (TFTs). These ITZO TFTs not only have extremely high mobility (∼40.19 cm2/V·s) but also perform perfectly in terms of long-term stability. By immobilizing the single-stranded DNA (ssDNA) probe on the channel region of the ITZO TFT, a biosensor capable of recognizing the gastric cancer biomarker miRNA 106a has been developed. Experimental results indicate that the biosensors demonstrate a linear responsitivity in the concentration range of 1 fM–1 μM, with a linearity of 99.03% and an ultra-low detection limit of 49.8 aM. Moreover, the biosensors show high stability, retaining 99.79% of its initial responsitivity even after one month of storage, along with good selectivity. These findings highlight the biosensor's potential for clinical applications, offering a promising approach to early gastric cancer screening.