本研究主要發展利用陽離子交換管柱及石墨爐原子吸收光譜儀測定綠藻食品中鈷胺（維生素B12）含量之快速方法，首先使用陽離子交換管柱除去自由型態鈷（II），接著利用石墨爐原子吸收光譜儀測定流洗液中有機鈷化合物之鈷含量，在選定的實驗條件下，方法偵測極限為24 μg /100 g。另外，本研究之方法確認乃利用添加鈷胺標準品於綠藻食品中，添加試驗之回收率範圍為98.3至99.5%，相對標準偏差為1.2~4.9%，結果顯示本方法可應用於綠藻食品中維生素B12之含量測定。

A method for the rapid determination of cobalamin (Vitamin B12) in chlorella food was proposed. This method utilized a strong cation exchange column to remove free cobalt (II), and the cobalamins were quantitatively determined by measuring total cobalt in the column effluent with graphite furnace atomic absorption spectrometry (GFAAS). Under optimized conditions, the method detection limit was 24 μg /100 g. The method was validated by spiking cobalamin standards in different chlorella food, recoveries from spike preparations ranged from 98.3 to 99.5%, with coefficients of variation of 1.2~4.9%. The results show the suitability of the proposed method for determining vitamin B12 in chlorella food.