A sensitive DNA biosensor for determination of mesalazine using PPy/Sponge-like Carbon/La3+-doped CuO nanocomposite

We conducted the present study to develop a sensitive and simple deoxyribonucleic acid (DNA) biosensor using a Polypyrrole/Sponge-like Carbon/La 3+ -doped CuO (PPy/SL-C/La 3+ -doped CuO) nanocomposite for mesalazine (MES) detection. The double-stranded (ds)-DNA-MES interaction was also analyzed by differential pulse voltammetry (DPV), docking method, and spectrophotometry. The signal of guanine oxidation on the electrode was obtained to detect MES using DPV. The relationship between MES concentrations (0.03 to100 μM) and peak current of guanine was linear under optimized conditions, with a limit of detection of 0.009 μM. The advantages of ds-DNA/PPy/SL-C/La 3+ -doped CuO/pencil graphite electrode were high sensitivity, potent reproducibility, and simplicity. The fabricated biosensor also successfully detected MES in real specimens such as urine, serum, and drug samples.