Preliminary Determination Of Vitamin B₂Based On The Graphene/Nafion Modified Glassy Carbon Electrode

In this paper electrochemical method measures VB₂was improved. The graphene wasprepared by hummers method, and it was modified to glassy carbon electrode. Transmissionelectron microscope （TEM）, scanning electron microscope （SEM）, X-ray diffraction （XRD）,fourier transform infrared spectroscopy （FT-IR） and cyclic voltammetry were used tocharacterize modified electrodes. The results showed that graphene was prepared successfully,the glassy carbon electrode was modified by graphene and Nafion. Modified electrodes wasused to measure VB₂.The determination conditions were established by means ofoptimization experiment. The influence of modifier on property, pH and pre-depositing timewere studied. The method was proved by the accuracy and precision of experiment whilecompared with pharmacopoeia specification determination. A relatively complete analyticalmethod of VB₂content was defined. The results showed that: the experimental condition wasoptimal when the amount of modifier was10μL（1mg/mL graphene and Nafion solution）, pHwas5.5, pre-depositing time was200s. The results showed that there was a good linearrelation between VB₂content and peak current when concentration range was between3.0×10^-62.0×10^-5mol/L. The standard curve regression equation was iP=1.1821C+4.7102,R2=0.9979. Detection limit is1.0×10^-6mol/L. The recovery rate was between97.8%⁹9.6%.The results showed a good agreement between this method and the pharmacopoeiaspecification determination of VB₂content. This method has a good accuracy andreproducibility based on determination results of pharmacopoeia specification. Besides, theinfluence of interfering ion in Determination of process on the determination results wasinvestigated. The results showed that C（VB₂）:C（X）=1:1and1:5, Fe³⁺, Zn²⁺, Ca²⁺, Pb²⁺and B₁,B₆, B₁₂variously increases peak current strength. Compared with the conventional method,this method has the following advantages: stronger anti-interference ability, lower analyticlimitation and higher stability. Besides, it is appropriate for the measurement of VB₂.