Electrochemical Micropyramid Array-Based Sensor for In Situ Monitoring of Dopamine Released from Neuroblastoma Cells

Abnormal dopamine neurotransmission is associated with several neurological and psychiatric disorders such as Parkinson's disease, schizophrenia, attention deficiency and hyperactivity disorder, and addiction. Developing highly sensitive, selective, and fast dopamine monitoring methods is of high importance especially for the early diagnosis of these diseases. Herein, we report a new ultrasensitive electrochemical sensing platform for in situ monitoring of cell-secreted dopamine using Au-coated arrays of micropyramid structures integrated directly into a Petri dish. This approach enables the monitoring of dopamine released from cells in real-time without the need for relocating cultured cells. According to the electrochemical analyses, our dopamine sensing platform exhibits excellent analytical characteristics with a detection limit of 0.50 ± 0.08 nM, a wide linear range of 0.01-500 μM, and a sensitivity of 0.18 ± 0.01 μA/μM. The sensor also has remarkable selectivity toward DA in the presence of different potentially interfering small molecules. The developed electrochemical sensor has great potential for in vitro analysis of neuronal cells as well as early diagnosis of different neurological diseases related to abnormal levels of dopamine.