electrochemical determination of dopamine based on derived cumof and reduced graphene oxide nancomposite

Abstract: dopamine (da) is a neurotransmitter that exists in the central nervous system of mammalians and regulates human cognition and emotions. in addition, it plays a significant role in cardiovascular, memory and hormonal systems. the normal level of dopamine in human serum and blood is 1-0.001 μm. the abnormal level of dopamine concentration in the human body is responsible for neurological diseases, such as parkinson’s disease, schizophrenia, and alzheimer’s disease. therefore, the design and fabrication of diagnostic tools for the determination of dopamine is important inside biological systems for proper diagnosis and treatment of associated disorders [1]. at present, there are several methods for determination of da, such as chemiluminescence, colorimetry, fluorescence and electrochemical methods. the electrochemical detection methods offer high sensitivity, low cost, and excellent selectivity. in recent years, metal−organic frameworks (mofs) and their derived compounds as inorganic organic hybrid multifunctional materials with fantastic features, such as a changeable skeleton structure, adjustable pore sizes, and exposed metal activity sites, attracted many attentions in the chemical sensor field [2, 3]. however, the poor electron conductivity of mofs will seriously suppress their electrochemical activity. up to now, the most common strategy to address the poor conductivity of mofs is to couple mofs with conductive materials such as carbon nanotubes, graphene oxide, reduced graphene oxide carbon nanofibers, and so on. reduced graphene oxide (rgo) has received a great deal of attention due to its high load-bearing mobility, high mechanical stiffness, environmental friendliness and large surface area [4]. in this study, a nanocomposite of cuo/c@rgo was designed as electrochemical sensing platform for the detection of dopamine. the cuo/c nanocomposite was synthesized by a facile approach via the calcination of cu-based metal organic framework (cu-mof). the as-prepared cuo/c/rgo nanocomposite was characterized using scanning electron microscopy (sem), x-ray diffraction spectroscopy (xrd), fourier transform infrared spectroscopy (ftir), energy-dispersive x-ray spectrum (eds). the effect of several parameters such as ph, scan rate were investigated. under optimal conditions, an excellent linearity range was obtained from 0.1 to 200 μm. finally, the cuo/c/rgo nanocomposite reveals an excellent da recovery rate through real samples (urine, serum samples) analyses.