Mucoadhesive sustained-release tablets for vaginal delivery of Curcuma comosaextracts: Preparation and characterization

The objectives of this study were to prepare and characterize the mucoadhesive vaginal tablets of Curcuma comosa(C. comosa) extract for local delivery of the active phytoestrogens in a sustained release manner. The oleoresin-like C. comosaextract was converted into apparently dry powder by adding it into the mixture of polymer, namely polycarbophil (PCP), hydroxypropylmethylcellulose (HPMC) or the blends of PCP:HPMC, and silica. The absence of interaction between C. comosaextract and excipients was confirmed using FTIR. C. comosamucoadhesive powder was directly compressed into 24-mm capsule shape tablets. All prepared tablets had acceptable physical properties and uniformity of diarylheptanoids (DAs), namely (3R)-1,7-diphenyl-(4E,6E)-4,6-heptadien-3-ol (DA1) and (3S)-1,7-diphenyl-(6E)-4,6-hepten-3-ol (DA2). Blending PCP with HPMC could improve swelling and mucoadhesive properties of the tablets (p < 0.05). In vitrorelease showed that DAs were released over a period of 72 h in a sustained manner. The almost complete DA release was found in the formulation prepared with HPMC, of which the mean dissolution time of DA1 and DA2 stood at 34.7 ± 4.1 and 32.1 ± 3.7 h, respectively. Stability study reveals that C. comosatablets were stable in terms of tablet properties, DA content and release characteristics when stored in a refrigerator.