Development of an Ion-Pairing Reagent and HPLC-UV Method for the Detection and Quantification of Six Water-Soluble Vitamins in Animal Feed

Table 2

Stability of six water-soluble vitamins.

Storage time (d)	Nicotinic acid	Nicotinamide	Folic acid	Pyridoxine	Riboflavin	Thiamine
1	98.70 ± 0.05	97.54 ± 0.14	99.83 ± 0.21	98.58 ± 0.02	97.66 ± 1.10	99.24 ± 0.20
2	96.57 ± 0.03	96.03 ± 0.02	89.01 ± 0.02	96.12 ± 0.54	95.69 ± 0.52	97.10 ± 0.66
3	94.29 ± 0.12	92.12 ± 0.24	63.38 ± 0.05	93.03 ± 0.86	94.44 ± 0.99	95.93 ± 1.65
4	85.32 ± 0.08	83.66 ± 1.03	60.93 ± 1.21	84.42 ± 0.39	84.93 ± 1.63	87.18 ± 1.87
5	70.85 ± 0.07	73.25 ± 0.08	56.24 ± 0.34	73.15 ± 1.09	71.03 ± 0.83	72.93 ± 0.39
6	63.03 ± 0.16	67.26 ± 0.12	52.62 ± 0.44	65.05 ± 1.21	66.38 ± 0.41	62.01 ± 0.33
7	59.63 ± 0.13	59.90 ± 1.08	49.59 ± 0.20	60.99 ± 0.50	58.99 ± 0.62	59.56 ± 0.72