A New Liquid Membrane Electrode for Selective Determination of Caffeine
نویسنده
چکیده
A new liquid membrane electrode for caffeine prepared from a solution of caffeine-picrylsulfonate ion-pair complex in n-octanol is developed. It exhibits Nernstian response in the range of w-·2 to 10M caffeine with a cationic slope of 59 mY/concentration decade. The electrode has a wide working pH range (5.59.5), fast response time (20 seconds1.5 minutes), stable response for at least 30 days and high selectivity for caffeine in the presence of many organic bases. The results obtained for quantitation of 1 1000 f.Lg mlof caffeine show an average recovery of 99.5% and a mean standard deviation of 1.3%.
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تاریخ انتشار 2004