"Fit-for-Purpose" Simultaneous Extraction of Water-Soluble Vitamins (PP, B2, B6, B9, B5) from Mineral Feeds and Premixes and Simultaneous Determination of B1 and Nicotinic Acid

A fast quantitative fit-for-purpose method has been developed for the simultaneous extraction of the water-soluble vitamins: nicotinamide (PP), riboflavin (B2), pyridoxine (B6), folic acid (B9) and pantothenic acid (B5) from mineral feeds and premixes, simultaneously determined together with thiamine (B1) and nicotinic acid. The single extractant for vitamins B2, B6, nicotinamide, B9 and B5 is a neutral buffer. The vitamins are separated and determined by ion-pair HPLC with a long (150 mm) C18 column using a mobile phase consisting of a gradient of phosphate buffer at pH 3 (phase A) and methanol (phase B) with selective detection at 214, 260 and 294 nm. A statistical study was conducted to assess recovery and uncertainty to verify fit-for-purpose characteristic of the method. Linearity, accuracy, repeatability, robustness, LOQ and LOD were also determined.