過ヨウ素酸ナトリウムを用いた血中ICG検査法の自動分析への試み

The IV infusion of indocyanine green (ICG) is done during liver and circulatory function examinations. The standard procedure is a manual operation using a spectrophotometer, sometimes requiring drawing of blood before and after the medication. Therefore, the results include two kinds of errors: the first is from the differences in skill between operators, and the second is from the properties of the serum sample, such as hemolytic hemoglobin and chyle. We aimed to resolve those problems. In this study, it did not need to be drawn before administration. Oxygenation of ICG with sodium periodate was used. The color of ICG at 805 nm disappears when sodium periodate is added. We applied this method to an automated biochemical analyzer, Hitachi7170. The average within-run CVs were 0.97 – 3.13% (n=10) at 0.1 – 1.0 mg/dL. When we used 55 serum samples with added ICG, the correlation between the values obtained with the present method (y) and the manual method (x) was: y = 1.04x (r=0.999, Syx = 0.01). The present method shows good performance evaluation and can be easily applied to automated analyzers.