Droplet size and composition of nutraceutical nanoemulsions influences bioavailability of long chain fatty acids and Coenzyme Q10

The influence of droplet size (d32 = 0.21, 0.70 or 2.2 μm) and oil digestibility (corn oil versus mineral oil) on the bioavailability of a model long chain fatty acid (heptadecanoic acid) and lipophilic nutraceutical (Coenzyme Q10) was investigated using a rat feeding study. Initially, we showed that small droplets were digested more rapidly than large droplets using a simulated small intestinal model (pH stat), which was attributed to the greater surface area of lipid exposed to intestinal juices. The pH stat model also confirmed that emulsified corn oil was digestible, whereas emulsified mineral oil was indigestible. A rat feeding study showed that the bioavailability of the fatty acid and lipophilic nutraceutical in small intestinal tissues was highest when they were encapsulated within digestible oil droplets with the smallest size. This study provides important information for development of nanoemulsion-based delivery systems that increase oral bioavailability of lipophilic nutraceuticals.