Table 2. HPLC operating conditions for vitamin B₃ analysis

Items	Nicotinic acid	Nicotinamide
Column temp.	15°C	15°C
Detector	UV 270.4 nm	UV 270.4 nm
Injection volumn	20 μL	20 μL
Flow rate	0.5 mL/min	1.2 mL/min
Mobile phase	(A) 5 mM sodium 1-hexanesulfonate(acetic acid 0.75%, triethylamine 0.02%)(B) Methanol	(A) 5 mM sodium 1-hexanesulfonate(acetic acid 0.75%, triethylamine 0.02%)(B) Methanol
Gradient condition	0 min: A 100%12 min: A 100%13 min: A 100%42 min: A 100%43 min: A 45% + B 55%50 min: A 45% + B 55%51 min: A 100%	0 min: A 100%19 min: A 100%20 min: A 100%41 min: A 100%42 min: A 45% + B 55%49 min: A 45% + B 55%50 min: A 100%