Modeling of diffusion transport through oral biofilms with the inverse problem method

Area of Science:

• Oral Microbiology
• Biophysics
• Mathematical Modeling

Background:

• Dental biofilms present a significant challenge to antimicrobial therapies due to their complex structure.
• Understanding the transport dynamics of molecules within these biofilms is crucial for developing effective treatments.

Purpose of the Study:

• To develop a quantitative mathematical model for passive macromolecule transport in dental biofilms.
• To establish a predictive tool for the diffusion and concentration of therapeutic agents within biofilms.

Main Methods:

• Utilized fluorescently labeled dextrans of varying molecular masses (3 kD to 2000 kD) as diffusion probes.
• Formed in vitro biofilms using key oral bacteria: Streptococcus mutans, Streptococcus sanguinis, Actinomyces naeslundii, and Fusobacterium nucleatum.
• Employed confocal laser microscopy to record diffusion processes and employed inverse problem methods for model construction.

Main Results:

• A mathematical function describing biofilm penetration was successfully constructed.
• The model enables analysis of the relationship between steady-state concentration, molecular weight, and penetration time.
• Demonstrated the ability to predict how different sized molecules diffuse through the biofilm matrix.

Conclusions:

• The developed model can predict the effective concentration and penetration time of anti-biofilm medications.
• An improved model for large molecule transport was proposed, incorporating exchange time at the biofilm surface.
• This research provides a foundation for designing more effective drug delivery strategies targeting dental biofilms.