Titanium dioxide-multiwalled carbon nanotube/polyimide composite film modified electrodes for simultaneous voltammetric detection of ascorbic acid, uric acid and dopamine as biomarker molecules.

Titanium dioxide-multiwalled carbon nanotube/polyimide (TiO2–MWCNT/PI) composite film modified electrodes for simultaneous detection of dopamine (DA), uric acid (UA), and ascorbic acid (AA) in clinical or biomedical applications were prepared. Firstly, TiO2–MWCNT and polyimide structures were synthesized. Then, TiO2–MWCNT/PI composites containing different ratios of MWCNT were subsequently prepared and characterized with chemical, thermal and morphological analysis techniques. Synthesized TiO2–MWCNT/PI composites were coated on the platinum electrode surface. Prepared electrodes were used to sense DA, UA, and AA with voltammetric measurements. LOD and LOQ parameters of modified electrodes for DA were observed 8.5114 μM and 25.5342 μM, respectively. The R2 value for the DA in the linear range from 175 to 325 µM was obtained 0.9967 (in the existence of AA and UA). After five repeatability results, 96.3% AA, 98.2% DA, and 88.3% UA peak currents were maintained. The modified electrode exhibited good selectivity, acceptable durability, high repeatability, and sensitivity. [ABSTRACT FROM AUTHOR]