Bi2WO6/Nb4C3Tx/dsDNA bio-nano-engineered composite as a powerful biosensor component to diagnose and monitor pemetrexed in pharmaceutical and environmental fluids

Abstract

Biosensors are powerful tools for fast and highly sensitive monitoring of biological fluids, especially chemotropic drug monitoring. In this regard, a bio-electrochemical nanostructure sensor was designed and engineered for the monitoring of pemetrexed, a breast and lung anticancer drug, in pharmaceutical and environmental fluids. In this design, Bi₂WO₆/Nb₄C₃Tx nanocomposite was synthesized as a conductive catalyst by hydrothermal method and characterized with XRD, SEM, FT-IR, XPS, and EDS methods. On the other hand, a screen-printed electrode (SPE) was adapted by layer-by-layer strategy and used as an analytical tool. Bi₂WO₆/Nb₄C₃Tx nanocomposite was used as the first layer and conductive substrate and salmon ds-DNA was engineered as the second layer and biological recognition element. The oxidation signal of guanine was selected as the best strategy to follow the intercalation behavior of pemetrexed with ds-DNA structure. The reduction in guanine signal was used to diagnose and sense pemetrexed as a fast strategy. Using this strategy and the bio-nano-engineered method, pemetrexed was detected in a concentration range of 0.01–100 µM with a detection limit of 2.8 nM. To investigate the strength of the engineered sensor in complex samples, a recovery range of 98.7–103.6% was obtained using Bi₂WO₆/Nb₄C₃Tx/ds-DNA/SPE. In the final step, the molecular docking study approves pemetrexed drug interacting with DNA receptors in an intercalation mode, which is well in accordance with the experimental investigations, and also, some kinetic parameters were calculated for this interaction process.