In the Herbalife Nutrition sample, I determined riboflavin (vitamin B2), pantothenic acid (vitamin B5), biotin (vitamin B7) and vitamin B12 using a high-performance liquid chromatography (HPLC). I evaluated the content of pantothenic acid using a standard additive. Content of riboflavin, biotin and vitamin B12 are determined using an external standard (calibration curve). In addition, I determined the content of two minerals, manganese and iron using atomic absorption spectroscopy (AAS). The concentration was determined using a calibration curve. I made two parallels and found the method to be very reproducible. I have found that the resulting values are in good correspondence with the declared values. The largest deviation is for iron content, where the resulting value is 15% higher than the declared value.
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