| dc.description.abstract | The mixture of eugenol, menthol, and methyl salicylate can be analyzed by near infrared spectrophotometry (NIRS) and compared with the chromatography gas analysis. The steps to validate NIRS as the analytical tool included feasibility test, calibration model building, prediction test, and validation test. The feasibility test produced low perturbation for NIRS FOSS Rapid Content Analyzer tool. The calibration model building used multivariate calibration (partial least square), with 2nd derivative curve. Prediction test gave the standard error prediction (SEP) for eugenol, menthol, and methyl salicylate of 0.019, 0.09, and 0.0145, respectively. Validity test for the mixture of eugenol, menthol, and methyl salicylate gave linearity of 0.858, 0.973, and 0.891, respectively. The range of value (%) were 67–119 for eugenol, 60–110 for mentol, and 69–120 for methyl salicylate. The value of accuracy, repeatability, intermediate precision, and specificity for the mixture were SEP > 1.4 × SEL, RSD < 2%, no significant difference, and > 0.900, respectively. Based on the results of prediction and validation test, NIRS is applicable for measurement of the mixture of eugenol, menthol, and methyl salicylate. | en |
