In the ever-evolving landscape of biomedical engineering, the search for more effective and safer drug delivery systems remains a focal point of research worldwide. A pioneering breakthrough has recently been achieved at the Institute of Nuclear Physics of the Polish Academy of Sciences (IFJ PAN) in Cracow, Poland. Scientists there have innovated wound dressings composed of electrospun polymer mats incorporating the antibacterial drug metronidazole, enabling controlled, localized drug release that promises to transform infection treatment in mucous membrane wounds without exposing the body to unwanted systemic effects.
The cornerstone of this novel technology lies in the technique of electrospinning—a sophisticated fiber production method that manipulates polymers into nanometer to micrometer-scale fibers. Electrospinning employs a high-voltage electrostatic field that draws out a spinning polymer solution through a needle towards a collector, forming ultra-fine fibers as the liquid undergoes chemical transitions such as solvent evaporation. This method enables the creation of mats with highly tunable physical properties, from fiber diameter and porosity to mechanical strength, facilitating precise control over drug release dynamics.
Central to the IFJ PAN study was the encapsulation of metronidazole, a well-studied antibacterial drug typically used to treat localized mucous membrane infections, such as periodontal disease. Direct administration of metronidazole is effective but is limited by its potential harmful side effects when it disperses throughout the body unintentionally. To circumvent this, researchers innovated a molecular delivery system that confines the drug within the fibers, designed to release metronidazole gradually and precisely over an extended period at the site of infection.
One of the technical triumphs of this research was mastering the choice and combination of polymers and coating materials suitable for the electrospinning process and compatible with metronidazole’s chemical profile. Researchers fabricated both homogeneous fibers—where the drug is evenly distributed throughout the polymer matrix—and more sophisticated core-shell fibers using coaxial electrospinning. The latter method uses a specialized needle-within-a-needle apparatus, allowing distinct polymer-drug mixtures to form a core surrounded by a polymeric shell, effectively controlling drug diffusion and protecting the drug’s molecular integrity.
Achieving reproducibility and stability in these mats required meticulous regulation of environmental and apparatus parameters during electrospinning. Factors such as ambient temperature, humidity, needle-to-collector distance, and collector design play critical roles in fiber morphology and resultant functional properties. Maintaining these parameters ensured the formation of uniform mats with fiber diameters narrowly confined between 0.7 and 1.3 micrometers—a range identified as optimal for maximizing drug absorption surface area and sustaining controlled drug release kinetics.
Initial in vitro tests demonstrated that these electrospun mats retain metronidazole within their fibers under dry storage, providing an airtight seal which prevents premature drug degradation. Upon exposure to wound exudate or physiological fluids, the fibers respond by becoming porous enough to commence a sustained release of the embedded drug. This reaction ensures the antibacterial agent is delivered directly and continuously at therapeutic concentrations exactly where required, minimizing systemic exposure and potential side effects.
However, the team found that metronidazole-containing mats have a shelf life limited to roughly one month. This constraint is not due to the polymer matrix or electrospinning technique but originates from the innate physical properties of metronidazole, which tends to crystallize after prolonged storage, affecting its release profile. Ongoing research aims to optimize formulations to extend this period or identify complementary drugs with improved stability for this platform.
The mats developed are currently produced at 2×2 centimeters dimension, reflecting a prototype scale recognizable for ease of application to wounds or infected mucous membranes. Their physical and chemical characteristics have been thoroughly characterized, laying a robust foundation for translational research with medical and clinical partners. This opens avenues for clinical trials evaluating efficacy, safety, and patient outcomes, paving the way for commercial and therapeutic deployment.
Electrospinning’s flexibility offers a wider landscape for future therapeutic delivery innovations. The successful incorporation of metronidazole highlights the method’s adaptability and suggests that other bioactive agents—antibiotics, anti-inflammatory drugs, or even growth factors—could be embedded similarly for targeted therapy. This could revolutionize dressing technologies, especially relevant for chronic wounds, burns, or surgical sites where controlled, localized treatment can significantly improve healing trajectories.
Professor Ewa Juszynska-Galazka, leading the project at IFJ PAN, underscored the universal potential of this delivery system. She pointed out that the polymeric and coating selection protocols developed could be tailored to accommodate a broad spectrum of molecular drugs, offering a customizable platform that pharmaceutical development can harness for diverse medical needs.
The IFJ PAN, renowned for its multidisciplinary excellence in physical and nuclear sciences, extends its expertise in applying advanced material engineering to biomedical challenges through this work. This project represents a confluence of polymer science, drug chemistry, and electrostatic engineering, supported by decades of research into particle physics and materials science, reinforcing Poland’s positioning at the forefront of applied physics with societal impact.
As the project progresses, collaboration with medical institutions is anticipated to refine not only the physical constructs but also to assess biocompatibility, immunological response, and pharmacodynamics in vivo. Translational medicine approaches, supported by the rigorous analytical frameworks mastered at IFJ PAN, will be vital in bridging this lab-scale innovation to bedside application.
Ultimately, this innovation embodies the synthesis of cutting-edge nanotechnology and pharmacology, heralding a new era in wound management. Electrospun mats with controlled drug release not only promise to reduce adverse effects associated with systemic antibiotic therapies but also to enhance patient compliance, improve therapeutic outcomes, and mitigate the growing threat of antibiotic resistance by enabling precise dosing.
Subject of Research: Controlled drug delivery using electrospun polymer mats containing antibacterial agent metronidazole for wound dressings.
Article Title: Electrospun Fiber Mats with Metronidazole: Design, Evaluation, and Release Kinetics
News Publication Date: April 3, 2025
References:
Adamczyk O., Deptuch A., Tarnawski T.R., Zieliński P.M., Drzewicz A., Juszyńska-Gałązka E. (2025). Electrospun Fiber Mats with Metronidazole: Design, Evaluation, and Release Kinetics. The Journal of Physical Chemistry B, 129(18), 4535–4546. DOI: 10.1021/acs.jpcb.5c00873
Image Credits: Source: IFJ PAN
Keywords
Electrospinning, Controlled drug release, Metronidazole, Wound dressing, Polymer fibers, Antibacterial therapy, Nanofiber mats, Coaxial electrospinning, Drug delivery system, Biomedical materials, Localized therapy, Polymer coatings
