2. Sample measurement
1. Clarify the sample by centrifugation at 8000 rpm with eppendorf centrifuge.
2. Mix 0.5 ml of clarified sample with 4.5 ml of 2,6-dichlorophenol indophenols.
3. Measure the absorbance of the resulting mixture at 515 nm by spectrophotometer
within 30 minutes. (Use 1% of meta-phosphoric acid as a blank)
4. If the absorbance > 1.0, dilute the sample into appropriate dilution with 1% of
meta-phosphoric acid and repeat the procedure No. 2-3.