Mucoadhesive delivery systems have attracted remarkable interest recently, especially for their potential to prolong dosage form resident times at sites of application such as the vagina or nasal cavity, thereby improving convenience and compliance as a result of less frequent dosage. Mucoadhesive capabilities need to be routinely quantified during the development of these systems. This is however logistically challenging due to difficulties in obtaining and preparing viable mucosa tissues for experiments. Utilizing artificial membranes as a suitable alternative for quicker and easier analyses of mucoadhesion of these systems is currently being explored. In this study, the mucoadhesive interactions between progesterone-loaded fibers (with varying carboxymethyl cellulose (CMC) content) and either artificial (cellulose acetate) or mucosa membranes are investigated by texture analysis and results across models are compared. Mucoadhesion to artificial membrane was about 10 times that of mucosa, though statistically significant ( p = 0.027) association between the 2 data sets was observed. Furthermore, a hypothesis relating fiber-mucosa interfacial roughness (and unfilled void spaces on mucosa) to mucoadhesion, deduced from some classical mucoadhesion theories, was tested to determine its validity. Points of interaction between the fiber and mucosa membrane were examined using atomic force microscopy (AFM) to determine the depths of interpenetration and unfilled voids/roughness, features crucial to mucoadhesion according to the diffusion and mechanical theories of mucoadhesion. A Kendall's tau and Goodman-Kruskal's gamma tests established a monotonic relationship between detaching forces and roughness, significant with p-values of 0.014 and 0.027, respectively. A similar relationship between CMC concentration and interfacial roughness was also confirmed. We conclude that AFM analysis of surface geometry following mucoadhesion can be explored for quantifying mucoadhesion as data from interfacial images correlates significantly with corresponding detaching forces, a well-established function of mucoadhesion.

a b s t r a c tNanofibres from mucoadhesive polymers could combine their material properties with unique structural characteristics for superior drug delivery performance. However, due to their chain structure a significant proportion of mucoadhesive polymers such as polysaccharides cannot be easily spun into fibres. In this study, we demonstrate the possibility of using polymer blends for the preparation of nanofibres that offer substantial mucoadhesive capabilities. Fibres from four different polymers were obtained by pressurised gyration at different working pressures and a rotation speed of 24,000 rpm. Electron microscopy indicates that structurally well-defined fibres with diameters from less than 100 nm upwards were successfully produced. Quantitative relationships between the physical properties and fibre characteristics were established while the fibre compositions were confirmed to contain features likely to confer mucoadhesive properties. Finally, a combination of texture analysis and atomic force microscopy was used to verify the benefit of transforming polymer powders into nanofibre structures, as far as mucoadhesive potential is concerned.

Recent evidence has continued to support the applicability of progesterone in preventing preterm birth, hence the development of an appropriate vaginal delivery system for this drug would be of considerable interest. Here, we describe the development of progesterone-loaded bioadhesive nanofibers using pressurized gyration for potential incorporation into a vaginal insert, with a particular view to addressing the challenges of incorporating a poorly water-soluble drug into a hydrophilic nanofiber carrier. Polyethylene oxide and carboxymethyl cellulose were chosen as polymers to develop the carrier systems, based on previous evidence of their yielding mucoadhesive nanofibers using the pressurized gyration technique. The fabrication parameters such as solvent system, initial drug loading and polymer composition were varied to facilitate optimisation of fiber structure and efficiency of drug incorporation. Such studies resulted in the formation of nanofibers with satisfactory surface appearance, diameters in the region of 400 nm and loading of up to 25% progesterone. Thermal and spectroscopic analyses indicated that the drug was incorporated in a nanocrystalline state. Release from the drug-loaded fibers indicated comparable rates of progesterone dissolution to that of Cyclogest, a commercially available progesterone pessary, allowing release over a period of hours. Overall, the study has shown that pressurized gyration may produce bioadhesive progesterone-loaded nanofibers which have satisfactory loading of a poorly water-soluble drug as well as having suitable structural and release properties. The technique is also capable of producing fibers at a yield commensurate with practical applicability, hence we believe that the approach shows considerable promise for the development of progesterone dosage forms for vaginal application.

The paucity of evidence-based data on formulation characteristics preferred by the children is known to limit the design of tailored paediatric dosage forms. The European Paediatric Translational Research Infrastructure (EPTRI) commissioned a study to evaluate children’s dosage forms perceived preferences in some European countries and explore the feasibility of using the young persons advisory groups (YPAGs) to involve children in formulation research. An online, age-adapted survey was developed and translated into six languages. The survey link was disseminated across seven European countries: Albania, Italy, the Netherlands, and Dutch-speaking part of Belgium, Romania, Spain, and the United Kingdom. Respondents’ (n = 1172) perceived preferences for oral dosage forms primarily differed based on age, health status, and experience. Conventional dosage forms, i.e., liquid (35%), tablets (19%), and capsules (14%), were the most selected. Liquid was widely selected by children less than 12 years and by those healthy and taking medicines rarely. Monolithic solid forms were mostly chosen by adolescents and by children with a chronic disease taking medicines frequently. There was a clear lack of familiarity with more novel dosage forms (e.g., orodispersible films and granules). Noteworthy, granules were not appreciated, particularly by adolescents (52.8%). To rationalise the creation of paediatric formulations, it is important to involve children as active stakeholders and to apply tools assessing children’s perspectives on medicines to inform acceptable dosage form development from the start.