A High-Performance Electrochemical Sensor Based on Ni-Pt Bimetallic Nanoparticles Doped Metal Organic Framework ZIF-8 for the Detection of Dopamine.

In this paper, microporous Zn-based zeolitic imidazolate framework with the sodalite cage structure (SOD-ZIF-8) was synthesized by the solvothermal method. Powder X-ray diffraction (PXRD), scanning electron microscopy (SEM) and N₂ adsorption were employed to characterize the synthesized material. An ultra-sensitive electrochemical sensor based on highly dispersed bimetallic Ni-Pt nanoparticles immobilized on zeolitic metal-organic framework ZIF-8 for dopamine quantification is introduced for the first time. The as-prepared Ni-Pt@ZIF-8 composite was deposited onto a glassy carbon electrode (GCE), serving as a sensor that exhibits superior properties for the detection of dopamine (DA). A Box-Behnken design was employed, and response surface methodology (RSM) was applied to investigate the impact of various experimental parameters on dopamine detection. The parameters optimized in this study included pH, drying time (hours), drop volume for deposition (μL), and accumulation time (minutes). The Box-Behnken experimental design enabled the systematic optimization of these factors to enhance the sensor's performance. Benefiting from the synergy of ZIF-8 and Ni-Pt bimetallic nanoparticles, the Ni-Pt@ZIF-8 composite exhibited high sensitivity towards dopamine, achieving a low detection limit of 1.0 nM. The sensor's linear response to dopamine (1 nM to 10 μM), resistance to interference, and high recovery in human serum, coupled with its simple fabrication, make it a promising tool for real-world dopamine detection.