ABSTRACT
Because it can not only directly reach the lesion site to play a local therapeutic effect, but also avoid the liver first pass effect and play a systemic therapeutic effect, vaginal mucosal administration has attracted more and more attention from domestic and foreign scholars in the treatment of vaginitis, cervicitis and other diseases. This article introduces the physiological characteristics of the vagina and discusses the factors affecting drug absorption. The vaginal mucosal drug-administered preparations, which are contained in the drug database of U.S. Food and Drug Administration(FDA) and China Food and Drug Administration(CFDA), and listed in the 2015 edition of Chinese Pharmacopoeia, are taken as the research objects. And the application of their dosage forms, indications and other aspects were sorted out and analyzed. The related literature on vaginal mucosal drug delivery systems in recent years was reviewed, and the dosages forms and in vitro and in vivo evaluation were summarized. Some problems in the study of vaginal mucosal drug preparations have been pointed out:①the western medicine preparations are widely used, and the related Chinese medicine preparations have been developed less; ②the majority of dosage forms are tablets, suppositories and other conventional dosage forms; ③there are few studies on the evaluation of vaginal mucosal preparations in vitro and in vivo. It is suggested that the future development of vaginal mucosal drug delivery system can be a useful attempt in the application of new technologies and methods, such as combination of drugs, high adhesion excipients, liposomes, etc;so as to provide reference for the application and improvement of vaginal mucosal drug delivery system.
ABSTRACT
Objective To prepare palmatine-loaded flexible nano-liposomes (PFL) films with Bletilla striata polysaccharide (BSP) as membrane material, and evaluate its pharmacy related performance in order to lay the foundation for further application. Methods The PFL was prepared by injection method and the films of PFL based on Bletilla striata polysaccharide (PFL-BPF) was prepared by homogenate coating method. The PFL-BPF was characterized and evaluated by electron microscopy, differential scanning calorimeter (DSC), and in vitro transmucosal membrane experiment. Results The PFL and BSP had good compatibility and easy to film with BSP as membrane material. The appearance of PFL-BPF obtained was smooth, non-bubble, flexible, and suitable stiffness; PFL-BPF had good biological adhesion. The time of scouring the film agent from mucous membrane with normal saline was (130 ± 7) min. At 0.5 h, the dose of PFL-BPF promoting palmatine (PA) infiltration to mucosa was 32.41 μg/g. It was 3.17 times higher than those of PA solution based on BSP (PL-BPF) and 1.9 times for PA common liposomes based on BSP (BLP + PA-BPF) (t-test, P < 0.05); At 2.5 h, it was 2.67 times and 1.89 times higher than those of PL-BPF and BLP + PA-BPF, respectively. It showed that PFL-BPF could significantly promote the water-soluble drug PA through mucosa membrane and release it slowly. The results of DSC showed that the possible mechanism for promoting the absorption of PA through mucosa membrane was that the flexible liposomes disturbed the mucosal epithelial cells and carried the drug into the mucosal tissue. Conclusion The PFL-BPF had the advantages of good film-forming property, lasting adhesive attraction, strong scour resistance, simple and feasible preparation process, and could promote drug permeation into mucosa obviously. Therefore, the flexible nano-liposomes film is a good drug carrier for the transmucosal drug delivery applications and has a wide application prospect.