Analysis of Rhodamine B in Chinese Wolfberry from Market Sale by HPLC

Based on the method of high performance liquid chromatography - diode array detector (HPLC - DAD) ,this experiment rapidly detected rhodamine B of Chinese wolfberry from market sale. Rhodamine B in the samples was dissolved by hexane.And after it was evaporated, it was extracted quantitatively.And then rhodamine B was measured with high performance liquid chromatography (HPLC) detector, using external standard method of peak area for quantitation. Results showed that the test conditions: 80 percent methanol and 20 percent water as mobile phase; sample volume was 20 μL ; column temperature was 35 degree centigrade; the flow rate was 1.0 ml per min and detection wavelength of 545nm, a reference to the wavelength of 600nm.Rhodamine B of the linear correlation coefficient was 0.9998 between the concentration of 0.06 and 0.20μg per ml. The stability of the method was in the range of 2.4 percent to 3.3 percent, precision was about 1.60 percent, recovery rate determination results were between 85.75 percent and 103.80 percent,The positive rate of rhodamine B was 80 percent. This method has the advantages of simple, rapid and accurate, and is very suitable for the determination of rhodamine B in Chinese wolfberry.