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Design of Experiment for Determination of Caffeine Content by Ultra Performance Convergence Chromatography

: An experiment of instrumental analysis for determination of caffeine content in beverages by Ultra Performance Convergence Chromatography (UPC 2 ) was designed. The caffeine in three beverages including coke, green tea and oolong tea was extracted and diluted by methanol. Then caffeine concentrations in beverages were measured by UPC 2 . Through this experiment, students could not only consolidate several laboratory skills such as weighing, constant volume and liquid transfer, but also master the basic theory, operation and data processing of UPC 2 .This experiment integrates the new chromatography into basic laboratory teaching, which can broaden students’ scientific horizons. It is conductive to cultivating students’ innovative spirit and practical ability.