Oxidation of Thiamine Tube 1 Tube 2 5 ml Sample 5 ml Sample 2.5 g NaCl 2.5 g NaCl 3 ml K3FeCN6 3 ml NaOH 13 ml Isobutanol 13 ml Isobutanol Centrifuge Centrifuge Tube 3 Tube 4 5 ml Standard (thiamin) 5 ml Standard (thiamin) 2.5 g NaCl 2.5 g NaCl 3 ml K3FeCN6 3 ml NaOH 13 ml Isobutanol 13 ml Isobutanol Centrifuge Centrifuge Thiamin Standard Solution = 0.2 mg/ml Calculation of B1 (mg of B1/5 ml assay sample) = (Tube 1 – Tube) / (Tube 3 - Tube 4 )Oxidation of Thiamine Tube 1 Tube 2 5 ml Sample 5 ml Sample 2.5 g NaCl 2.5 g NaCl 3 ml K3FeCN6 3 ml NaOH 13 ml Isobutanol 13 ml Isobutanol Centrifuge Centrifuge Tube 3 Tube 4 5 ml Standard (thiamin) 5 ml Standard (thiamin) 2.5 g NaCl 2.5 g NaCl 3 ml K3FeCN6 3 ml NaOH 13 ml Isobutanol 13 ml Isobutanol Centrifuge Centrifuge Thiamin Standard Solution = 0.2 mg/ml Calculation of B1 (mg of B1/5 ml assay sample) = (Tube 1 – Tube) / (Tube 3 - Tube 4 )