Preparation and evaluation of oral capsules containing apigenin nanocrystals prepared by ultrasonication

This work aims to enhance dissolution rate, increase absorption and bioavailability of Apigenin by formulating it as nanocrystal suspension employing ultrasonic technology. Two different diluents; (5%, 10%) microcrystalline cellulose (MCC) and (2%, 3%) anhydrous lactose were used to prepare hard gelatin capsules for two optimum types for apigenin nanocrystals prepared in our laboratory utilizing ultrasonication technique using 1% tween 80 (F6) and 2% poloxamer 188 (F20). The results showed that the marketed capsules (containing MCC) had about half the dissolution rate than all the prepared nanocrystals capsules formulas, and the nanocrystals prepared with poloxamer gave 90% release within 20 minutes and 100% release with 2 hours with excellent flow properties with no effect of the added diluents while the addition of diluents improved significantly the release of nanocrystals capsules (F6) with 1% tween 80 with good flow properties. The results suggested that utilizing apigenin nanocrystals prepared by ultrasonication technique may improve drug absorption and bioavailability with a reduced required dose.