| Determination the Citrinin of Red Yeast by HPLC
a .Phosphate acid b. Nanopure water
c. Methanol (HPLC)
HPLC (Shimadzu) Analytical balance (1/10000) Ultrasonic cleaner
0.45μm PTFE filter 50ml volumetric flask Screw cap vials
3) HPLC condition
Column: Polaris C18 5μm , 4.6×250mm
Detector: UV 245nm
Mobile Phase: A:=0.1% Phosphate acid B: Methanol
Flow Rate: 1.1ml/min
Accurately weigh 30mg extraction into 50ml volumetric flask. Add Methanol to volumetric flask and sonicate to mix, cool to room temperature and add Methanol to volume,filter through a 0.45μm PTFE filter into a screw cap vial and proceed with the analysis.
Standard preparation /calibration
Prepare a standard solution approximately 0.15mg/ml in methanol using a standard of Citrinin，Sonicate for about 10 minutes and transfer to screw-cap vials and can be stored in the refrigeration.
Determine the peak areas of the Citrinin on the sample chromatogram and compare to the corresponding peaks in the chromatogram for the standard solution. Calculate the weight percent .