Quantification of six bioactive compounds in Zhenqi Fuzheng preparation by high-performance liquid chromatography coupled with diode array detector and evaporative light scattering detector

A simple and accurate high-performance liquid chromatography（HPLC）coupled with diode array detector（DAD）and evaporative light scattering detector（ELSD）was established for the determination of six bioactive compounds in Zhenqi Fuzheng preparation（ZFP）.The monitoring wavelengths were 254,275 and 328 nm.Under the optimum conditions,good separation was achieved,and the assay was fully validated in respect of precision,repeatability and accuracy.The proposed method was successfully applied to quantify the six ingredients in 31 batches of ZFP samples and evaluate the variation by hierarchical cluster analysis（HCA）,which demonstrated significant variations on the content of these compounds in the samples from different manufacturers with different preparation procedures.The developed HPLC method can be used as a valid analytical method to evaluate the intrinsic quality of this preparation.

Determination of AF and AFG in Red Ginseng by High Performance Liquid Chromatography with Evaporative Light Scattering Detector (HPLC-ELSD)

[Objective]The paper was to establish a method for determining AF and AFG in red ginseng.[Method]A new simple,rapid and sensitive method for simultaneous determination of two amadori compounds,arginyl-fructose(AF)and arginyl-fructosyl-glucose(AFG),in extracts of three kinds of ginseng preparations was developed and validated using high performance liquid chromatography with evaporative light scattering detector(HPLC-ELSD).Two target analytes were efficiently separated by Prevail CTM18 column(4.6 mm×250 mm,5μm)at the flow rate of 0.8 mL/min within 15 min of single chromatographic run.[Result]Under optimized conditions,the detection limits were 0.015 and 0.02 mg/mL for AF and AFG,respectively.Calibration curves of peak area for two analytes were linear over three orders of magnitude with the correlation coefficients greater than 0.999.The average recoveries,precision,reproducibility and stability for two analytes(AF and AFG)were 99.5% and 100.9%,0.43% and 0.47%,0.46% and 0.43%,0.41% and 0.49%,respectively.[Conclusion]This method was successfully applied for quantifying AF and AFG in red ginseng and the method was efficient,sensitive and accurate.

Determination of azithromycin in raw materials and pharmaceutical formulations by HPLC coupled with an evaporative light scattering detector

A simple high-performance liquid chromatography(HPLC)method coupled with an evaporative light scattering detector(ELSD)was developed for the determination of azithromycin in raw materials and pharmaceutical formulations(injections,capsules and tablets)without any pretreatment or derivatization step.Azithromycin,degradation products and formulation ingredients were separated efficiently by using the mobile phase consisted of ammonium acetate(0.05 M,pH 8.0)and acetonitrile(60:40,v/v)in an isocratic mode at 0.8 ml/min flow rate.Parameters of ELSD were 60
C for evaporation temperature and 50 psi for pressure of carrier gas(air).A logarithmic calibration curve was obtained from 50.93 to 509.30 mg/ml(r¼0.9996)for azithromycin,with the limit of detection(LOD)of 6.75 mg/ml(S/n¼3)and the limit of quantification of 22.50 mg/ml(S/n¼10).The developed method was validated and applied with satisfactory accuracy and precision for the determination of azithromycin in raw materials and pharmaceutical formulations(recovery 99e102%,RSD<1.2%,n¼3).No significant difference(t-test)was found between the results of the developed HPLCeELSD method and the HPLCeUV or microbiological method.