Determination of erythromycin A in erythromycin enteric-coated tablets by near infrared diffuse reflectance spectrophotometry

Objective:Near infrared diffuse reflectance spectrophotometry(NIRDRS)and chemometrics were applied to the quantitative analysis of erythromycin A in erythromycin enteric-coated tablets.Method:PLS(partial least squares)regression models were set up using a calibration set(40 samples).The validation set was set up by 10 sam- ples.Applying this model to predict the validation set and detect the samples.Results:The determination coefficients R~2 was 99.86 as indicated from the cross-validation,the true mean predictive error RMSECV(root mean square error of cross validation)was 0.50.The mean prediction error RMSEP(root mean square error of prediction)obtained from the validation was 0.493,The correlation coefficient of the true value and prediction value from validation was 0.9995.The average recovery of the prediction set was 100.11%(RSD=0.96%,n=10).Conclusion:NIRDRS method is simple,rap- id and accurate.The method can be applied in rapid qualitative and quantitative analysis of drugs.