利用分光光度法測定中藥中的鐵含量

Determination of Iron in Traditional Chinese Medicine by Spectrophotometer

在pH8.8～9.0時，鐵離子以氫氯化羥胺還原產生亞鐵離子，亞鐵離子再與鄰二氮菲產生橙紅色錯合物，用UV-Vis分光光度計於波長510nm測定鐵離子濃度。利用不同煮沸時間加熱迴流測定當歸及黃耆中的鐵離子含量，結果顯示當歸及黃耆在加熱迴流一小時後有較佳的萃取效果。上述結果確效試驗中，與感應藕合電漿原子放射光譜儀（ICP）結果做比較，兩者測定值誤差<2％。當歸與黃耆中的鐵離子含量分別為247.37±6.72（ug/g）及189.57±9.47（ug/g），且在總重量固定情形下，當歸與黃耆不同比例混合加熱煎煮測定鐵離子含量，結果顯示當歸與黃耆重量比例為1：4混合煎煮時，鐵離子含量較高。研究結果顯示當歸及黃耆在適當的比例配方，具有較佳的療效。In pH 8.8~9.0 , the iron(Ⅲ) ion (Fe3+) is reduced to iron(Ⅱ) ion (Fe2+) by hydroxylamine hydrochloride, then iron(Ⅱ) ion (Fe2+) the combined with 1,10-phenanthroline produces a nacarat complex. The content of iron ion was determined by UV-Vis spectrophotometer at 510 nm. The results of using different refluxing time to obtain the iron ion content of the Angelicae Sinensis and Astragalus Membranous showed that we could get the best extraction effects at 60 minutes refluxing time. The accuracy these results, compared with that of ICP, were less than 2%. Each content of iron ion was 247.37 ±6.72 (ug/g) and 189.57±9.47 (ug/g), respectively. While the total weight remained unchanged, the content of iron ion in proportionally varying mixture of Angelicae Sinensis and Astragalus Membranous was measured, the result showed the content of iron ion was higher when Angelicae Sinensis and Astragalus Membranous ratio was 1:4. The results provide reliable data to assess the treatment of the disease, when Angelicae Sinensis and Astragalus Membranous ratios are appropriate.