| Keywords [eng] |
Microfluidic chip fabrication, Bacterial biofilms, Polymicrobial biofilms, Biofilm cultivation, Controlled flow conditions, Antimicrobial biofilm treatment, Static biofilm growth versus dynamic. Mikrofluidinės sistemos gamyba, Bakterijų bioplėvelės, Polimikrobinės bioplėvelės, Bioplėvelių auginimas, Kontroliuojamo srauto sąlygos, Antimikrobinio poveikio įvertinimas bioplėvelėms, Bioplėvelių auginimas statinėmis ir dinaminėmis sąlygomis. |
| Abstract [eng] |
Microbial biofilms are a group of microorganisms that are embedded in an extracellular polymeric matrix (EPS) and live in a coordinated manner. They cause challenging–to–treat chronic infections or complications related to implantable medical devices, such as urinary catheters, due to their increasing resistance to antibiotics. Recognising this critical issue in the medical field, traditional biofilm study methods often fail to accurately replicate the natural conditions, such as fluid flow, that play a crucial role in biofilm formation. Recognising current limitations in biofilm study, a microfluidic chip, using off–stoichiometry thiol–ene (OSTE) resin and cyclic olefin copolymer (COC) substrates, was created. The chip consisted of five independent growth chambers, enabling the simultaneous growth of several species of bacteria in one run under controlled fluid flow. The fabricated microfluidic chip is compatible with standard laboratory workflows, enabling real–time analysis and offering a user–friendly approach. To further emphasize the benefits of the fabricated chip's capabilities to study biofilm, the growth of Pseudomonas aeruginosa and Staphylococcus aureus was compared under static (24–well plate) and dynamic conditions (microfluidic chip). Analysis using confocal laser scanning microscopy revealed that under static conditions, biofilms were thicker, uneven with heterogeneous structures, while under dynamic conditions, biofilms were more uniformly distributed and thinner. To demonstrate the chip's capability for evaluating antibiotic efficacy, a treatment with ciprofloxacin at 5 µg/mL and different concentrations of tetracycline was performed, leading to significantly reduced biofilm and viability. Additionally, polymicrobial biofilm, consisting of Escherichia coli and Staphylococcus aureus, was cultivated under static and dynamic conditions. While polymicrobial biofilm did not form under static conditions, it successfully grew under dynamic conditions. Apart from that, to confirm the chip's capability to accurately mimic experimentally relevant fluid flow, computational simulations of wall shear stress were performed. These results highlight the microfluidic platform’s capabilities to advance biofilm research as a cost–effective, scalable, and reliable tool in a clinical setting. |
