ABSTRACT
@#To prepare a minocycline hydrochloride microsphere depot and evaluate its release performance and physicochemical properties, poly (lactic-co-glycolic acid) (PLGA) was used as raw material, the minocycline hydrochloride microspheres were prepared by electrospray, and the morphology and size distribution of the microspheres were characterized by polarizing microscopy and scanning electron microscopy (SEM). The microspheres were then mixed with sucrose acetate isobutyrate (SAIB) depot at a ratio of 1:10 to form a minocycline hydrochloride microsphere depot, and its release performance and porosity changes were evaluated. The results showed that the microspheres had smooth surface and the diameter was (5.294 ± 1.222) μm. After the microspheres were added into SAIB depot, the burst release of minocycline hydrochloride significantly decreased from 60% to 3.27% at the first day, and then the release lasted for 42 days . Additionally, the porosity of the depot increased rapidly from (12.53 ± 0.43)% to (32.53 ± 0.43)% during days 0-15, and increased slowly from (32.53 ± 0.43)% to (33.81 ± 0.54)% during days 15-45. The minocycline hydrochloride microsphere depot prepared in this study is expected to be an effective way for the application of minocycline hydrochloride for its good release performance and simple preparation process.
ABSTRACT
Ageratina glabrata (Kunth) R.M. King & H. Rob., Asteraceae (syn. Eupatorium glabratum Kunth) is widely distributed throughout Mexico and popularly known as "chamizo blanco" and "hierba del golpe" for its traditional use as external analgesic remedy. Though glabrata species has been chemically studied, there are no experimentally asserted reports about possible analgesic effects which can be inferred from its genus Ageratina. To fill the gap, we evaluated A. glabrata extracts in an animal model of nociception exploiting thermal stimuli. NMR and mass analyses identified a new thymol derivative, 10-benzoiloxy-6,8,9-trihydroxy-thymol isobutyrate (1), which was computationally converted into a ring-closed structure to explain interaction with the COX-2 enzyme in a ligand-receptor docking study. The resulting docked pose is in line with reported crystal complexes of COX-2 with chromene ligands. Based on the present results of dichloromethane extracts from its dried leaves, it is safe to utter that the plant possesses analgesic effects in animal tests which are mediated through inhibition of COX-2 enzyme.