An ultra-sensitive dopamine electrochemical sensor based on PVP/rGO-MWCNT composites

Abstract 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-MWCNT were encapsulated using a hydrothermal method to form a composite material. The composite was then characterized using scanning electron microscopy (SEM). The three materials were combined, and based on this, a new DA electrochemical sensor was constructed. It is worth noting that the high specific surface area and high conductivity of rGO-MWCNT cooperate with the amphiphilic and stable dispersion of PVP, which further improves the electrochemical performance of the sensor for DA. Under optimal conditions, DA content is detected within a wide range and with a low detection limit which is explained by the electrochemical redox process of the sensor. In addition, the sensor shows satisfactory recovery and accuracy in detecting DA content in real human serum samples using the standard addition method.