Abstract
As a key biomolecule for neurotransmission, dopamine (DA) is responsible for many neurological syndromes. Hence, effective DA detection is vital for the rapid-diagnosis of diseases caused by irregular DA levels. Therefore, we designed a non-enzymatic DA sensor using the novel gold-decorated porous silicon-poly-3-hexylthiophene (Au@PSi-P3HT) nanocomposite fabricated glassy carbon electrode. We employed a simple stain etching technique followed by ultra-sonication and photo-reduction techniques to synthesize this novel Au@PSi-P3HT nanocomposite. The structural, morphological, and surface characterizations of the Au@PSi-P3HT nanocomposite were performed using various analytical tools. TEM and FESEM images revealed that gold nanoparticles were randomly dispersed onto the PSi-P3HT sheet-like structure. In the electrochemical investigations, the Au@PSi-P3HT/GCE sensor showed excellent sensitivity (0.5112 μAμM−1cm−2), wide linear dynamic range (LDR = 1.0–460 μM), and reasonably low detection limit (LOD ∼0.63 μM). This newly designed DA sensor was also employed to check the potential chemical interference using several common biomolecules and the obtained results confirmed its selectivity during DA detection. The Au@PSi-P3HT/GCE sensor also exhibited satisfactory results in detecting DA levels in human blood serum and dopamine hydrochloride injection samples. Besides, the Au@PSi-P3HT/GCE sensor displayed superb reproducibility, repeatability, and stability. This novel Au@PSi-P3HT nanocomposite-modified GCE may emerge as a successful means for further designing effective non-enzymatic electrochemical sensors.
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•Au@PSi-P3HT modified GCE was used as an efficient dopamine electrochemical sensor.•Good sensitivity 0.5112 μAμM−1cm−2, very low LOD 0.63 μM and wide LDR 1.0–460 μM were obtained.•Excellent reproducibility, repeatability and operational stability of the modified electrode were observed.•Satisfactory results were observed in detecting DA in human blood serum and dopamine hydrochloride injection.