Fluorescence determination of vitamin B2 (nuclear lutein).

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the principles of .Vitamin B2 (nuclear lutein) is yellow-green fluorescent at wavelengths of 440 to 500 nm. The fluorescence intensity in the solution is directly related to the concentration of vitamin B2. The adsorption effect of silicon magnesium adsorbent on vitamin B2 was used to remove the impurities in the sample that interfered with fluorescence determination, and then vitamin B2 was removed to determine its fluorescence intensity. The test fluid was then added to sodium sulphate (Na2S2O4), vitamin B2 was reduced to a fluorescent-free substance, and the fluorescence intensity of residual fluorescent impurities in the test fluid was determined, the difference between the two is the fluorescence intensity produced by vitamin B2 in food.reagents
and equipment 1, reagents 0.1 mol/L hydrochloric acid; 1 mol/L sodium hydroxide; 0.1 mol/L sodium hydroxide; 20% (w/v) sodium dithionate solution; Washer solution: acetone, ice acetic acid, water (5 plus 2 plus 9); 0.04% bromophenol green indicator; 3% (v/v) potassium permanganate solution; 3% (v/v) hydrogen peroxide solution; 2.5mol/L sodium aqueous acetate solution; silica adsorbent: 60 to 100, sigma products.10% papaya protease: made with 2.5mol/L sodium acetate solution. It is now provisioned when used.10% amylase: made with 2.5mol/L sodium acetate solution. It is now provisioned when used.preparation of vitamin B2 standard liquid: A) vitamin B2 standard reserve liquid (25 sg/mL): put the
standard
vitamin B2 powder crystallization in a vacuum
drying
. After 24 hours, accurately weigh 50 mg, put in a 2L capacity bottle, add 2.4mL of ice acetic acid and 1.5mL of water. Shake the bottle in warm water, allow it to dissolve, cool to room temperature, dilute to 2L, move to the brown bottle, cover the surface of the solution with a little toluene, and store in the refrigerator.. B) Vitamin B2 standard liquid: Absorb 2.00mL vitamin B2 standard reserve liquid, placed in a 50 ml brown capacity bottle, diluted with water to the scale. Avoid light and store in a refrigerator at 4 degrees C for one week. This solution is equivalent to 1.00 μg of vitamin B2 per milliliter., the materialfresh pig liver or dried soybeans., equipmenttest tube
1.5×20cm (×4); pipe pipe 10mL (×1), 1 mL (×2); capacity bottle 100mL (×1), 10mL (×1); high-pressure disinfectant, electric
string
culture
boxes, vitamin B2 adsorption, fluorescence
phosphotometer
.operation method first, sample extraction1. Hydrolysing: 2 to 10g samples (about 10 to 200 mg of vitamin B2) are added to a 100ml triangular bottle, with 50mL 0.1mol/L hydrochloric acid, stirred until the particles are dispersed evenly. With 40 ml
the
the cap, the high-pressure hydrolytic sample at 121 degrees C 30min. After the hydrolytic solution was cooled, the drops were added with 1mol/L sodium hydroxide and the pH was adjusted to pH of 4.5 with 0.04% bromophenol green as an external indicator.2. Enzymatic solution: A hydrolytic solution containing starch: 3 ml of 10% amylase solution is added to keep warm at about 16h at 37 to 40 degrees C. High-protein hydrolytic solution: plus 3 ml 10% papaya protease solution, at 37 to 40 degrees C about 16h.3.
filtration
: the above enzyme lysate is fixed to 100 ml, filtration. This extract can be stored for one week in a refrigerator at 4 degrees C. .