Specific determination of myo-inositol in multivitamin pharmaceutical preparations by a flow injection system using a myo-inositol dehydrogenase reactor coupled with a glucose eliminating enzyme reactor.
A flow injection system for myo-inositol determination in multivitamin pharmaceutical preparations using two enzyme reactors was developed. Myo-inositol was detected using a fluorophotometer, to measure the fluorescence of NADH produced from NAD+ by a myo-inositol dehydrogenase reactor (IDR) containing myo-inositol dehydrogenase immobilized on porous glass. Enhanced interference due to excess glucose included in a multivitamin pharmaceutical preparation as a sweetener was eliminated by a glucose eliminating reactor (GER) co-immobilized with three enzymes (glucose oxidase, mutarotase and catalase). The calibration coefficient for the standard curve was 0.9993 for myo-inositol detection in the range of 1-5 microg/ml. Myo-inositol was determined even in the presence of glucose concentrations of 140-420 microg/ml. The recovery of myo-inositol added to the multivitamin pharmaceutical preparation was 99.6% (n=9).
Ono
Masaki
M
Analytical Laboratory, Self-Medication Laboratories, Taisho Pharmaceutical Co., Ltd., Yoshino-Cho 1-Chome, Kita-Ku, Saitama-Shi, Saitama 331-9530, Japan. masaki.ono@po.rd.taisho.co.jp
Nakajima
Toshiaki
T
Itoh
Yuji
Y
Shimada
Kenji
K
Yamato
Susumu
S
D004793:Enzyme Reactivators / Q000032:analysis; D017022:Flow Injection Analysis / Q000379:methods; D005947:Glucose / Q000032:analysis*; D007294:Inositol / Q000032:analysis*; D010088:Oxidoreductases / Q000032:analysis; D004364:Pharmaceutical Preparations / Q000032:analysis; D014815:Vitamins / Q000032:analysis*
D004793:Enzyme Reactivators; D004364:Pharmaceutical Preparations; D014815:Vitamins; D007294:Inositol; D010088:Oxidoreductases; D005947:Glucose