Photothermal enhanced biosensing platform of Fe3O4@CS-Au-Lac for dopamine detection
As a biomarker of endocrine gland diseases, the rapid and accurate determination of dopamine has a great significance. The aim of this study was to improve the dopamine biosensing performance of the Fe 3 O 4 @CS-Au-Lac (laccase immobilized on Fe 3 O 4 @CS-Au nanocomposites) by using the photothermal effect of magnetic carriers. Electrochemical impedance spectroscopy measurements revealed that the Fe 3 O 4 @CS-Au nanocomposites enhanced the electron transfer between laccase and the electrode. The Fe 3 O 4 @CS-Au-Lac biosensor presented an ultra-fast response to substrates, accurately detected dopamine within 0.2 s. Dopamine biosensing assays demonstrated that the Fe 3 O 4 @CS-Au-Lac biosensor possessed high sensitivity, remarkable tolerances towards organic compounds and metal ions, and excellent selectivity and stability. Amperometric curves indicated that the illumination brought a higher current to the biosensor compared to the dark environment. The Fe 3 O 4 @CS-Au-Lac biosensor held a low detection limit of 0.79 μM (S/N = 3) and a broad linear range of 1–1000 μM under the irradiation. Most significantly, the Fe 3 O 4 @CS-Au-Lac biosensor provided reliable results in the photothermal analysis of dopamine in synthetic urine samples. This finding paves the way for using the Fe 3 O 4 @CS-Au-Lac biosensor for photothermal detection of dopamine in biomedical applications.
危险品化学品经营许可证（带存储）