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Abbott Nutrition Division
Simultaneous Determination of Total Vitamin B
6,
B
2,
B
3
and B
1
in Infant
Formula Products by LC-MS/MS Using Enzymatic Digestion
d)
Riboflavin
Riboflavin is readily soluble in dilute alkaline solutions and is only sparingly soluble in
water although the solubility of Riboflavin increases in the presence of aromatic compounds
including Niacinamide. Crystalline Riboflavin is stable but in solution it is destroyed by UV
radiation and visible light. Aqueous solutions between pH=2 and pH=5 are heat stable whereas
alkaline solutions are unstable. Riboflavin is stable in the presence of oxygen. Total Riboflavin
activity consists of riboflavin, flavin mononucleotide (FMN) and flavin adenine dinucleotide
(FAD) predominately. Aqueous Riboflavin solutions exhibit absorbance maxima at 223 nm, 266
nm, 373 nm and 445 nm.
The molecular formula for Riboflavin is C
17
H
20
N
4
O
6
and its molecular weight is 376.37 g/mol.
Common synonyms include vitamin B
2
and 7,8-dimethyl-10-ribitylisoalloxazine.
The CAS# for Riboflavin is 83-88-5.
The chemical structure of Riboflavin is shown below:
e)
Thiamin Chloride Hydrochloride
Thiamine Chloride Hydrochloride is readily soluble in water, soluble in glycerol, sparingly
soluble in ethanol and insoluble in organic solvents. Thiamine Chloride Hydrochloride powder is
hygroscopic. Dilute acidic solutions of Thiamine Chloride Hydrochloride are relatively stable to
heat but stability decreases as solution-pH increases. Thiamine, thiamine phosphate and thiamine
diphsophate are to the primary components contributing to the total vitamin B1 activity.
The molecular formula for Thiamine Chloride Hydrochloride is C
12
H
18
Cl
2
N
4
OS and its
molecular weight is 336.27 g/mol.
N
N
N
N
H
2
C C C
H
C
OH
H
OH
H
CH
2
OH
OH
H
3
C
H
3
C
O
O
23
BVIT-02
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DO NOT DISTRIBUTE