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Abstract
Reference materials are important tool in chemical analysis in terms of provision of traceability of the measurement results to the SI units. A Pure substance certified reference material from caffeine and matrix certified reference material of milk chocolate were developed for the content of caffeine and theobromine, theophylline and caffeine respectively. Homogeneity and stability of the prepared reference materials were studied and characterization was done by two independent analytical methods. The measurement results were statistically treated and the certified values of caffeine is 99.862 %±0.649 in pure substance certified reference material (caffeine) and they were 1393.2± 21.569, 0.499 ±0.054 and 112.48±3.897 mg/kg for theobromine, theophylline and caffeine in milk chocolate certified reference material which makes the candidate reference materials very useful as a calibrant and for quality achievement in chemical analysis