Alginate-Based Patch for Middle Ear Delivery of Probiotics: A Preliminary Study Using Electrospray and Electrospinning

Featured Application Our work shows the application of electrospinning and electrospray to develop a tympanic membrane patch based on alginic acid, aimed at delivering probiotics and/or postbiotics to the middle ear. The possibility of contrasting chronic infections using probiotics is an emerging strategy, proposed as an alternative to antibiotics. Middle ear bacteriotherapy mediated by a probiotic/alginate patch can open new therapeutic routes in otology for those patients with chronic otitis media.Abstract Antimicrobial resistance poses a growing challenge in respiratory tract diseases like otitis media, often necessitating surgical interventions due to pharmacological treatment limitations. Bacteriotherapy, involving probiotics and/or their bioproducts, emerges as a promising alternative in such a scenario. This study aims to pave the way to middle ear bacteriotherapy by developing an innovative sodium alginate (SA)-based probiotic delivery system using electrospinning and electrospray techniques. Electrospray enabled the precise production of probiotic-laden SA microparticles, demonstrating potential for targeted bacterial delivery. By overcoming challenges due to the SA molecular structure, we successfully electrospun SA-based fiber meshes with poly(ethylene oxide) (PEO) as a support polymer. The rheologic behavior of the probiotic/SA solutions and the morphology of the obtained microparticles and fibers was evaluated, along with the diameter variation over time. The cytocompatibility of the produced microparticles and fibers was assessed using human dermal keratinocytes and their antimicrobial activity was tested against E. coli. The incorporation of probiotic-laden SA microparticles within electrospun SA/PEO fiber meshes finally offered a patch-like structure to be applied on the tympanic membrane or on the outer auditory canal, which could be a versatile and ideally safe treatment strategy in chronic otitis media. This innovative approach holds promise for clinical applications dealing with inflammatory processes, infections and dysbiosis, thus possibly addressing the complex healing process of chronic upper respiratory diseases while mitigating antimicrobial resistance.