Determination of nicotinamide (NA) using its polarographic catalytic wave in the presence of KIO3.
Nicotinamide (NA) yields a polarographic catalytic wave with a peak potential -1.38 V (vs. SCE) in 0.1 mol/L HAc-NaAc (pH 4.7)/4 x 10(-3) mol/L KIO3 buffer solution. The sensitivity of the catalytic wave increased in one order of magnitude as compared to that of the responding reduction wave without KIO3. Based on this observation, a new method for the determination of NA was recommended. The second order derivative peak current was proportional to the NA concentration in the range of 5 x 10(-8)- 6 x 10(-7) mol/L. 0.11-fold vitamin B1, 0.13-fold B2, 0.14-fold B6 and 8-fold nicotinic acid amounts do not interfere the determination of 1 x 10(-6) mol/L NA. The proposed method was used to determine the NA content in multivitamin tablets, with good agreement to the declared amount.
Institute of Electroanalytical Chemistry, Northwest University, Xi'an, People's Republic of China. eact@nwu.ed.cn
J
J
Song
Y
Y
Su
W
W
Guo
D006863:Hydrogen-Ion Concentration; D007452:Iodates / Q000737:chemistry / Q000494:pharmacology*; D009536:Niacinamide / Q000032:analysis* / Q000592:standards; D011048:Polarography / Q000592:standards; D017680:Potassium Compounds / Q000737:chemistry / Q000494:pharmacology*; D011736:Pyridoxine / Q000494:pharmacology; D013831:Thiamine / Q000494:pharmacology
D007452:Iodates; D017680:Potassium Compounds; D009536:Niacinamide; C039693:potassium iodate; D011736:Pyridoxine; D013831:Thiamine