Square Wave Voltammetric Determination Of Caffeine In Coffee

A carbon paste electrode was utilized for monitoring caffeine using square wavernvoltammetry (SWV). This method was applied to determine the caffeine levels in somerncoffee samples. Optimal experimental conditions for the analysis were found to be asrnfollows: pH value of 6 for the suporting electrolyte, SW frequency of 30 Hz, SWrnamplitude of 40 mV, and step potential of 7 mV. Having these optimum conditions arnlinear range was observed with in the concentration of 0 ~ 250 mg/L. For caffeinernconcentration of 50 mg/L, the detection limit three times the standard deviation inrnmeasured concentration (n=6) was found to be (10.67μg/mL). This method was appliedrnfor the determination of the caffeine levels in Ethiopian green coffee samples. Therncaffeine content of Ethiopian green coffee samples ranged from 0.9 - 1.16 % on dry massrnbasis. The quantities are in good agreement with those reported in the literature forrnCoffea arabica. The results are also in good agreement with values determined by HPLCrnmethod.rnKey words: Square Wave Voltammetry, Coffee, Caffeine and Carbon Paste Electrode

Get Full Work

Report copyright infringement or plagiarism