Electrochemical sensing of dopamine using nanostructured silver chromate: Development of an IoT-integrated sensor

Dopamine, one of the most important neurotransmitters, plays a crucial role in the functions of human metabolism, as well as the cardiovascular, central nervous and hormonal systems. This study focuses on the synthesis of nanostructured silver chromate and their application in dopamine sensing. The nanoparticles were synthesized using a complexation-mediated route using aminosalicylic acid as a stabilizer, resulting in uniform particles ranging from 3 to 15 nm in size. The synthesized silver chromate was characterized using X-ray diffraction, transmission electron microscopy and X-ray photoelectron spectroscopy techniques. Electrochemical studies revealed that the silver chromate exhibit excellent catalytic activity for the detection of dopamine. The electroanalysis provided the selective recognition of dopamine with the limit of detection of 1.05 μM and sensitivity of 2.68 μA μM⁻¹ cm⁻² in a linear range of 5–45 μM. Additionally, a portable, IoT (internet of things)-integrated sensor based on the synthesized silver chromate was developed using Arduino Uno R4 Wi-Fi module, enabling real-time monitoring of dopamine with data transmission to a cloud platform.