Spectrophotometry In Pharmaceutical Analysis - The Ginkgo Flavone, Nicotinamide Analysis Methods

This thesis studies the analytical methods of determination of Nicotinamide, N-hydroxymethylnicotinamide and flavonoids of Ginkgo biloba by Ultraviolet-visible Spectrophotometry and Atomic Absorption Spectroscopy. Three determinate methods of flavonoids of Ginkgo biloba and a new method of Nicotinamide and N-hydroxymethylnicotinamide by Ultraviolet Spectrophotometry are reported .The methods had been applied to determine the samples and obtained satisfactory results. It includes six parts as follows:Part I : Review. A review of the application of Ultraviolet-visible Spectrophotometry and Atomic Absorption Spectroscopy in Pharmaceuticals is given.Part II: Spectrophotometry of Nicotinamide by Coordination reaction of Ferric Chloride. A new method of spectrophotomertry of Nicotinamide by coordination reaction of Ferric chloride was studied. This basis is that the acetamido group of Nicotinamide could react with hydroxylamine to form N-hydroxylamine-amide, which gives color reaction with Fe3+ and could be used determination of Nicotinamide by spectrophotometry at the wavelength of 496nm. The linear region was 10.0~200.0 u g/mL, r=0.9997, e =5.11 X104 L mol-1 cm-1, RSD=1.2%,the average recovery was 101.2% .Part III: Determination of N-hydroxymethylnicotinamide by Potassium permanganate oxidation. A new method of Determination of N-hydroxymethylnicotinamide by Potassium permanganate oxidation was studied. The hydroxy group of N-hydroxymethylnicotinamide could react with Potassium permanganate, which reduced color of Potassium permanganate and was used determination of N-hydroxymethylnicotinamide by spectrophotometry at the wavelength of 526nm. The linear region was 2.0~40.0 ug/mL, r=0.9994, e =1.80X 104L mol-1 cm-1, the average recovery was 100.5%.Part IV: Indirect Determination of flavonoids of Ginkgo biloba.by AtomicAbsorption Spectroscopy. An atomic absorption spectroscopy was used for indirect determination of flavonoids of Ginkgo biloba via pb (II) precipitate. In the method, the flavonoids of Ginkgo biloba reacted with pb2+ and led to brown-yellow precipitate. The precipitate is centrifuged to subside. The pb2+ in supernatant is determined by AAS. The calibration curve was linear for flavonoids of Ginkgo biloba in the range of 5.0 ~ 30.0 v. g/mL, r=0.9995, RSD=1.7% and the recovery is 98.0-100.3%(n=10).Part V : Determination of flavonoids of Ginkgo biloba by aluminum chloride spectrophotometry. A new method for determining of flavonoids of Ginkgo biloba by aluminum chloride spectrphotometry was studied. The basis is that flavonoids of Ginkgo biloba could react with aluminum chloride. The linear region was 2.0~ 110.0 u g/mL, r=0.9999, and the recovery was 99.7-100.8%.Part VI: Determination of flavonoids of Ginkgo biloba by sodium tungstate spectrophotometry. A new method for determining of flavonoids of Ginkgo biloba by sodium tungstate spectrphotometry was studied. It based on which flavonoids of Ginkgo biloba could react with sodium tungstate to form yellow ester tungstate. The linear region was 4.0~90.0 u g/mL,R2=0.9997, and the recovery was 100-100.6%.