Mechanisms influencing viability and product qualities along the process chain of manufacturing probiotic oral films (ProOFs)

• Applicant: Dr. Jan Henrik Finke
• Subject Area: Mechanical Process Engineering ; Pharmacy
• Term: since 2024
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 537669582

The health effect of probiotic dosage forms depends on the viability of the microorganisms contained and the targeted colonization of the destination. In addition to the gastrointestinal tract, the oral cavity is one of the particular main areas of application for probiotics. Accordingly, dosage forms are needed which, on the one hand, are associated with low stress and damage to the sensitive microorganisms during production and, on the other hand, allow targeted release, e.g. in the mouth. Oral films, which disintegrate rapidly in the mouth after ingestion, are a suitable dosage form for this purpose. However, the production of oral films with living microorganisms has so far been insufficiently investigated and the influence of different process and formulation parameters on viability, especially in interaction with physical-mechanical film properties, is unknown. In the first phase of the project, films will be produced with the probiotic bacterium Ligilactobacillus salivarius and influencing process variables and thus damage mechanisms during suspension production, film casting and drying as well as formulation parameters such as type and concentration of film former and additives will be systematically identified. For this purpose, suitable methods for microbiological and physical-mechanical film characterization as well as for detailed assessment of the drying of the film will first be developed and impelented. To enable a comprehensive evaluation of the products, the storage stability will be investigated and the influence of various parameters such as temperature and humidity will also be determined. The identified product properties will be correlated with specific product structures. Their elucidation will be supported by suitable model experiments, e.g. to determine the shear and temperature tolerance of the bacteria and the influence of various surface-modified particles on the film mechanics, in order to enable the most mechanistic modeling possible of the microbiological and physical-mechanical film properties. The generated understanding of stress mechanisms, their intensity and the damage to the bacteria should enable a rational design of formulation and drying parameters for targeted improvement of survival rate and storage stability. The extent to which developed formulation strategies, that can be generalized and transferred to other microorganisms could be derived, will be investigated in the second phase of the project. This will be achieved by analogously studying five other probiotic microorganisms and determining the transferability of the dependencies identified on the basis of one strain and the areas of application of the derived models. At the same time, possibilities for improving the dosage form, e.g. by increasing the mucoadhesiveness or additional loading of the films, will be examined.

• DFG Programme: Research Grants