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Abstract Otitis media (OM), known as a middle ear infection, is the leading cause of antibiotic prescriptions for children. With wide-spread use of antibiotics in OM, resistance to antibiotics continues to decrease the efficacy of the treatment. Furthermore, as the presence of a middle ear biofilm has contributed to this reduced susceptibility to antimicrobials, effective interventions are necessary. A miniaturized 3D-printed microplasma jet array has been developed to inactivatePseudomonas aeruginosa, a common bacterial strain associated with OM. The experiments demonstrate the disruption of planktonic and biofilmP. aeruginosaby long-lived molecular species generated by microplasma, as well as the synergy of combining microplasma treatment with antibiotic therapy. In addition, a middle ear phantom model was developed with an excised rat eardrum to investigate the antimicrobial effects of microplasma on bacteria located behind the eardrum, as in a patient-relevant setup. These results suggest the potential for microplasma as a new treatment paradigm for OM.
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Direct Laser-Functionalized Au-LIG Sensors for Real-time Electrochemical Monitoring of Response of Pseudomonas aeruginosa Biofilms to Antibiotics
Pseudomonas aeruginosa(P. aeruginosa) is a phenazine-producing pathogen recognized for its biofilm-mediated antibiotic resistance, showing up to 1000 times higher resistance compared to planktonic cells. In particular, it is shown that a phenazine called pyocyanin promotes antibiotic tolerance inP. aeruginosacultures by upregulating efflux pumps and inducing biofilm formation. Therefore, real-time study of phenazine production in response to antibiotics could offer new insights for early detection and management of the infection. Toward this goal, this work demonstrates real-time monitoring ofP. aeruginosacolony biofilms challenged by antibiotics using electrochemical sensors based on direct laser functionalization of laser induced graphene (LIG) with gold (Au) nanostructures. Specifically, two routes for functionalization of the LIG electrodes with Au-containing solutions are studied: electroless deposition and direct laser functionalization (E-Au/LIG and L-Au/LIG, respectively). While both methods show comparable sensitivity (1.276 vs 1.205μAμM−1), E-Au/LIG has bactericidal effects which make it unsuitable as a sensor material. The effect of antibiotics (gentamicin as a model drug) on the production rate of phenazines before (i.e., in planktonic phase) or after biofilm formation is studied. The sensor data confirms that theP. aeruginosabiofilms are at least 100 times more tolerant to the antibiotic compared to planktonic cells. The biosensors are developed using a scalable and facile manufacturing approach and may pave the way toward simple-to-use antibiotic susceptibility testing devices for early infection diagnosis and real-time study of antibiotic resistance evolution.
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- PAR ID:
- 10475373
- Publisher / Repository:
- The Electrochemical Society
- Date Published:
- Journal Name:
- ECS Sensors Plus
- Volume:
- 2
- Issue:
- 4
- ISSN:
- 2754-2726
- Format(s):
- Medium: X Size: Article No. 041601
- Size(s):
- Article No. 041601
- Sponsoring Org:
- National Science Foundation
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