Posted by drug-cyclodextrin (CD) inclusion complexes are often used to improve the solubility of a drug and/or mask its bitterness. This study aimed to evaluate the bitter masking effect of CDs on different drugs using NMR-ROESY analysis, human sensory tests, and e-tongue measurements. The strength of inclusion complex formation between drugs and CDs was investigated by NMR-ROESY, and these results were compared to human sensory test results. In the sensory test, participants identified which drug-CD inclusion complexes were not bitter.
The electrical tongue was not able to detect the taste of any of the drug-CD inclusion complexes.
Mixing time in the ROESY experiment is the parameter that shows the distance of dipolar interaction among protons in the molecules. It was hypothesized that shorter mixing times indicate short drug-CD distance in the stronger inclusion complex formation, and therefore also efficient bitter masking effect.
The Correlation hypothesis of bitterness and proximity between drugs and CD by the NMR-ROESY method
Experimental hypothesis figure showing the shorter mixing time reveals efficient bitter masking effect due to detecting the stronger inclusion
Ueda T, Yamaguchi MS, Christian-Tabak L, Takai Y, Tode C. Quantifying the bitter masking effect of drug-cyclodextrin complexation: NMR-ROESY mixing time approach. Carbohydr Res. 2024 Mar 1;537:109067. doi: 10.1016/j.carres.2024.109067.
Featured image credit to Image Source/Alamy