Determination of Aloin A, Aloin B, and Aloe-Emodin in Raw Materials and Finished Products Using HPLC Multi-Laboratory Validation Study, AOAC 2016.09, Final Action Status.

Background: A multi-laboratory validation study was performed on AOAC Official Method of Analysis (OMA) 2016.09, for final action. Eight different laboratories throughout the world participated in the study tested the same set of 6 different laboratory samples of raw materials (commercial) and formulated products (commercial), and all the laboratories successfully generated results within the acceptance criteria.

Objective: The intention of the study was to evaluate specificity, precision (variation), linearity/range, system suitability, limit of detection (LOD), and limit of quantitation (LOQ) by multiple laboratories to satisfy the requirement of moving the OMA 2016.09 to the final action status. Accuracy and ruggedness were already validated in earlier work of single laboratory validation (1), and it was not necessary to include these validation parameters in the multi-laboratory validation study.

Method: Laboratory samples containing Aloe were sent out to participating laboratories. Each lab followed AOAC 2016.09 (First Action status) to analyze contents of aloin A, aloin B, and aloe emodin using high performance liquid chromatography (HPLC) instrument. The results generated by each laboratory were collected and evaluated.

Results: The specificity results show that blank and matrix chromatograms do not contain major interfering peaks on the retention time of aloin A, aloin B, and aloe-emodin. The precision (variation) results of duplicated preparations are not more than 0.05 parts per million (ppm) different. The linearity/range results from six standards (10 parts per billion (ppb), 20 ppb, 40 ppb, 80 ppb, 160 ppb, and 500 ppb) have correlation coefficient (R) value of ≥ 0.999. The system suitability results meet the acceptance criteria to show the instrument validity. The limit of detection (LOD) results show that the signal-to-noise (S/N) ratio of 10 ppb standards for all three components are about 3. The limit of quantitation (LOQ) results show that the S/N ratio of 20 ppb standards for all three components are about 10.

Conclusions: The validation parameters (specificity, precision (variation), linearity/range, system suitability, LOD, and LOQ) have been successfully analyzed, and it shows that the test method is suitable for its intended use.

Highlights: The test method has been successfully validated by the eight different laboratories around the world (US, UK, Germany, and Canada). Each of the laboratory is managed independently by the site lab management team. This multi-lab study validated the method of Determination of Aloin A, Aloin B, and Aloe-Emodin in Raw Materials and Finished Products Using high performance liquid chromatography (HPLC), and the method fits for its intended purpose.