Dissolution profile study on the novel doxycycline hydrochloride sustained-release capsules.

In present study, a novel doxycycline hydrochloride (DC) sustained-release capsule was prepared with the new manufacturing technology, extrusion-spheronization method. The release studies were performed using marketed sample as a reference and data were analyzed in terms of cumulative release amounts as a function of time. Results demonstrated that our developed sample was similar to reference preparation in release characteristics in vitro. The in vitro release characteristics of different batches of preparations were quite similar with each other, the total release proportions of DC from sustained-release capsule reached higher than 90 % within 4 h. Similarity factors f2 of two preparations were all higher than 50, the release mechanism of drugs from capsules fitted to non-Fichian diffusion.The developed sustained-release preparation may be a promising alternative dosage form for treatment of related diseases.