Electrochemical and MEMS-based biosensors for quantifying ALDH1A1 expression and activity in non-small cell lung cancer cell lines

Aldehyde dehydrogenase 1A1 (ALDH1A1) is a key biomarker in cancer cells, associated with cancer stem cell properties and drug resistance. Quantifying and analyzing ALDH1A1 activity in cancer cells can provide crucial insights into cancer progression and mechanisms of resistance to treatment. This study explores the application of biosensors in detecting and measuring ALDH1A1 levels in two non-small cell lung cancer cell lines (NSCLC) (A549 and NCI-H1299) and assessing enzyme activity. We used advanced biosensor technology to evaluate enzyme expression in cell lines tested and their functional activity using specific substrates and cofactors of ALDH1A1 compared to their exposure to a known inhibitor. Our results demonstrate that biosensor-based assays can accurately measure ALDH1A1 expression and functional activity, distinguishing between different cancer cell populations. In addition, a complementary theoretical MEMS-based cantilever biosensor model was developed that shows predictable resonance frequency shifts with binding to ALDH1A1, thus providing a predictive framework for quantitative diagnostics and sensor optimization. These biosensors offer high sensitivity, specificity, and real-time monitoring capabilities, providing a valuable tool to understand the role of ALDH1A1 in cancer biology, developing targeted therapies, and improving clinical outcomes. • Development of a highly sensitive electrochemical biosensor for ALDH1A1 detection, enabling quantitative measurement of protein expression at ultra-low concentrations in non-small cell lung cancer (NSCLC) cell lines. • The biosensor distinguishes between A549 and H1299 cell populations and evaluates functional enzyme activity in real time, including inhibitor response, exceeding the limitations of conventional semi-quantitative methods. • Integration with a MEMS-based cantilever biosensor model demonstrates resonance frequency shifts proportional to ALDH1A1 binding, providing a predictive framework for diagnostic applications, drug screening, and targeted cancer therapy.