Determination of artemisinin and moisture content of Artemisia annua L. dry powder using a hand-held near infrared spectroscopy device

A rapid, low-cost method, based on near-infrared spectroscopy (NIR), was developed to determine artemisinin and moisture content in dry powder of Artemisia annua (A. annua) leaves. A calibration set of 60 samples and validation set of 40 samples of A. annua hybrids exhibiting artemisinin content of between 0.7% and 1.6% was used. Results of partial least squares modelling indicated that NIR was accurate in predicting artemisinin content. Root mean square error values of cross-validation (RMSECV) and prediction (RMSEV) of 0.1% were calculated, in both cases. A model of moisture content was particularly accurate with RMSECV and RMSEP values of 0.8% (R=0.99) and 1.4%, respectively.