Water-Soluble Vitamins (1)
Vitamins are essential components for maintaining physiological functions in living 
bodies. In particular, five water-soluble essential vitamins, B
1, 
B
2, C, nicotinic acid and nicotinamide are sometimes 
lacking in human bodies. The necessary quantities of three water-soluble vitamins, 
B
6, B
12 and folic acid have 
been determined by the NRC (National Research Council), though these vitamins 
are seldom lacking in human bodies. This chromatogram shows an example of the 
analysis of such water-soluble vitamins except folic acid. This analysis has been 
performed by reversed phase mode with gradient elution. Good calibration curves 
are obtained for the vitamins using RSpak 
DE-413 (a column 
for reversed phase chromatography). As an example, calibration curves for vitamin 
B
2 and vitamin B
6 are shown 
below. 

Sample : 20micro-L
1. 
Vitamin C 
2. 
Niacin 
3. 
Vitamin B6 
4. 
Niacinamide 
5. 
Vitamin B1 
6. 
Vitamin B12 
7. 
Vitamin B2
Column       : Shodex RSpak DE-413 (4.6mmID*150mm)
Eluent       : (A); 1/30M Potasium phosphate buffer(pH6.8)/CH3CN=98/2
               (B); H2O/CH3CN=50/50
               0min to 4 min, 100% (A) 
               4min to 15 min, 100% (A) to 30% (A)
               after 15 min, 30%(A) 
Flow rate    : 0.6mL/min
Detector     : UV(254nm)
Column temp. : 35deg-C