An Ultrasensitive Dopamine Electrochemical Sensor Based on PVP/rGO-MWCNT Composites

Dopamine (DA) is a neurotransmitter secreted by the brain that plays a variety of roles in the central nervous system. An imbalance in dopamine can cause a range of disease symptoms and negative effects, such as Parkinson’s disease and arrhythmia. Detecting DA accurately and rapidly is therefore crucial for medical diagnosis and disease prevention. In this study, PVP and rGO-MWCNTs were encapsulated via a hydrothermal method to form a composite material. The composite was then characterized by scanning electron microscopy (SEM). The three materials were combined, and on this basis, a new DA electrochemical sensor was constructed. Notably, the high specific surface area and high conductivity of the rGO-MWCNTs cooperate with the amphiphilic and stable dispersion of PVP, which further improves the electrocatalytic activity of the sensor for DA. Under optimal conditions, the DA content is detected within a wide range and has a low detection limit, which can be explained by the electrochemical redox process of the sensor. In addition, the sensor shows satisfactory recovery and accuracy in detecting the DA content in real human serum samples via the standard addition method.