BS ISO 20637:2015 pdf odwnload – Infant formula and adult nutritionals — Determination of myo-inositol by liquid chromatography and pulsed amperometry

BS ISO 20637:2015 pdf odwnload – Infant formula and adult nutritionals — Determination of myo-inositol by liquid chromatography and pulsed amperometry 6.1.1.3 Dry blended powder samples For dry blended/non-homogenous powder samples, reconstitute per the product label instructions. Accurately weigh 0,5 g to 5 g reconstituted product into a 100 ml volumetric flask. Record the mass to the nearest 0,000 1 g. 6.1.1.4 Wet blended powder samples For wet blended/homogenous powder samples, accurately weigh 0,25 g to 1,5 g powder into a 100 ml volumetric flask and record the mass to the nearest 0,000 1 g. Add approximately 10 ml to 15 ml water to the volumetric flask and swirl or stir to completely dissolve the powder. 6.1.2 Extraction Add enough 0,5 % hydrochloric acid (4.2.5) to each sample to adjust the sample pH to 4,5 ± 0,2 and swirl to mix. Allow the samples to react with 0,5 % hydrochloric acid for a minimum of 2 min and then dilute to volume with water. Mix well. Filter samples through filter paper (5.15) into 125 ml conical flasks or appropriate glassware. NOTE Although some samples will filter cloudy, the filtrates can still be used. Filter an aliquot of sample filtrate through a 0,45 μm syringe filter (5.14) into an autosampler vial. 6.2 Myo-inositol bound as phosphatidylinosito 6.2.1 Sample preparation 6.2.1.1 General Prepared samples that are constantly stored at 1 °C to 8 °C in closed containers are stable for up to 5 days. After 5 days, samples shall be prepared again. Thoroughly mix or stir products prior to sampling. Mix liquid samples well to ensure homogeneity. If the powder sample homogeneity is unknown, assume that it is non-homogenous and proceed with the preparation of dry blended/non-homogenous powder samples given in 6.2.1.3. 6.2.1.2 Liquid samples For ready-to-feed liquid samples, accurately weigh (4 ± 0,4) g of product into a 50 ml centrifuge tube and record the mass to the nearest 0,000 1 g. 6.2.1.3 Dry blended powder samples For dry blended/non-homogenous powder samples, reconstitute per the product label instructions. Accurately weigh (4 ± 0,4) g reconstituted sample into a 50 ml centrifuge tube. Record the mass to the nearest 0,000 1 g. 6.2.1.4 Wet blended powder samples For wet blended homogenous powder samples, accurately weigh (1 ± 0,1) g powder into a 50 ml centrifuge tube and record the mass to the nearest 0,000 1 g. Add 4 ml water centrifuge tube...