Purpose: U.S. sales of botanical supplements have steadily increased for the last 13 years (by 7.7% of all DS sales in 2016).Botanical DS are sold as capsules (hard shell and soft gel), tablets, powders and tinctures. Disintegration and rupture tests measure the time it takes for a tablet or capsule to break apart under specific controlled conditions. They are two of several important tests used for quality control of dosage forms.
Methods: As a part of the botanical initiative for the Dietary Supplement Ingredient Database (DSID), representative green tea and turmeric DS were identified using DSLD (Dietrary Supplement Label Database), industry sales data, internet and local store research and analyzed for their phytochemical content. In addition, tablets, hard shell capsules and soft gels were tested for disintegration/rupture. They were immersed and agitated in the appropriate media and visually inspected for disintegration after 15 or 30 minutes, in accordance with the United States Pharmacopeia’s (USP) General Chapter 2040.
Results: Both simple (single botanical ingredient) and complex (includes other botanicals and/or other non-botanical ingredients) green tea and turmeric DS were tested. In-house quality control materials and duplicate products from a single lot showed consistent results when tested over time. The overall pass rate for simple green tea dosage forms was 55% with 2-3 lots tested over time. The first 2 lots purchased within a 6 month time frame had consistent results for disintegration (16 of 29 (55.1%) products passed in both lots; 12 of 29 (41.4%) products failed in both lots; 1 of 29 (3.4%) products had mixed results). An additional lot purchased the next year for many of the products showed more inconsistency in results for disintegration testing (8 (36.4%) products passed in all lots; 8 (36.4%) products failed in all lots; 6 (27.3%) products with mixed results). The overall pass rate for complex green tea DS was 66.6% (22 of 36 (61.1%) products passed in both lots; 10 of 36 (27.7%) products failed in both lots; 4 of 36 (11.1%) products had mixed results).
Across both GT studies for the first two lots, soft gels were most likely to pass disintegration (100% pass rate; 5 of 5 products with all lots). With the hard shell capsules, the overall pass rate was 68.7% (31 of 48 passed in both lots; 13 of 48 failed in both lots; 4 of 48 had mixed results). Tablets were least likely to pass disintegration (pass percentage was 20.8 % (2 of 12 passed in both lots; 9 of 12 (75%) failed in both lots; 1 of 11 (only 9.1%) had mixed results).
Simple and complex turmeric DS were also tested for disintegration. The overall pass rate for turmeric dosage forms was 85% (17 of 20 products X 1 lot). Testing of additional 30 products with 2 lots is underway. For the first 20 products, the dosage form results followed the same pattern as the green tea DS. All soft gels passed (n=4). Hard shell capsules passed at a rate of 84.6% (11 of 13 passed). For tablets, the pass percentage was lower, at 66.6% (2 of 3 passed).
The capsule material may also play a role in the disintegration of DS. Products in capsules were categorized as having either cellulose-based (non-gelatin) or gelatin-based shells by reviewing label information. The pass rate of gelatin capsules was higher than non-gelatin capsules (simple green tea DS (2-3 lots n=75): 82.7% vs. 39.5%; complex green tea DS (2 lots n=70): 83.3 % vs. 75%. Our disintegration data are in line with the results of a recent study by Glube et al., 2013, that indicated better performance of capsules made from gelatin vs. non-gelatin shells.
Conclusion: It is important to investigate the quality of DS dosage forms. We established the presence of a significant disparity in performance quality among both commercial Green Tea and turmeric DS. Dosage form appeared to have an impact on disintegration test results for Green Tea DS. In three DS pilot studies, soft gel capsules were most likely to pass disintegration, hard shell capsules less likely, and tablets were least likely to pass disintegration.
Karen Andrews– USDA
Pavel Gusev– USDA
Laura Oh– USDA
Phuong-Tan Dang– USDA
Renata Atkinson– USDA
Pamela Pehrsson– USDA
Johanna Dwyer– NIH
Joseph Betz– National Institutes of Health (NIH)
Adam Kuszak– NIH
Rebecca Costello– NIH
Leila Saldanha– NIH