{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,8,7]],"date-time":"2026-08-07T15:27:02Z","timestamp":1786116422298,"version":"build-2736575974"},"reference-count":44,"publisher":"MDPI AG","issue":"15","license":[{"start":{"date-parts":[[2026,8,6]],"date-time":"2026-08-06T00:00:00Z","timestamp":1785974400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>Antimicrobial resistance (AMR), largely driven by the inappropriate and excessive use of antibiotics, requires rapid and reliable bacterial detection and antibiotic susceptibility testing (AST), as conventional culture-based methods remain time-intensive. Here, we report a real-time, label-free interdigitated wave electrode array (IWEA) that combines dielectrophoretic (DEP) enrichment with impedance spectroscopy for rapid bacterial detection and AST. The proposed IWEA was designed and optimized via COMSOL Multiphysics to enhance DEP-relevant electric-field strength, thereby improving DEP-assisted bacterial enrichment compared to conventional planar interdigitated electrodes. The platform enabled sensitive detection of both Gram-positive (Staphylococcus aureus) and Gram-negative (Escherichia coli) in 0.1\u00d7 PBS across 10\u2013105 CFU\/mL within 30 min using DEP-assisted preconcentration (100 kHz, 10 Vpp), outperforming passive (non-DEP) operation (102\u2013105 CFU\/mL). For AST, bacterial responses to vancomycin, gentamicin, and ampicillin were monitored through impedance variations following DEP-based enrichment. Susceptible bacteria produced concentration-dependent reductions in \u0394Z\/Z0, whereas resistant bacteria showed similar responses to untreated controls. Quantitative assessment yielded CC50 values of 2.86 \u00b1 0.22 \u00b5g\/mL and 3.06 \u00b1 0.20 \u00b5g\/mL for vancomycin and gentamicin against S. aureus, and 4.59 \u00b1 0.30 \u00b5g\/mL for gentamicin against E. coli. Resistance profiles of S. aureus to ampicillin and E. coli to vancomycin and ampicillin were clearly distinguished. SEM imaging and disk diffusion assays independently validated the impedance-derived susceptibility results. Collectively, this IWEA platform offers a rapid, label-free, and quantitative approach for bacterial detection and AST, with strong potential for antimicrobial screening and point-of-care diagnostics.<\/jats:p>","DOI":"10.3390\/s26154984","type":"journal-article","created":{"date-parts":[[2026,8,6]],"date-time":"2026-08-06T09:46:38Z","timestamp":1786009598000},"page":"4984","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Dielectrophoretic Enrichment Coupled with Impedance Spectroscopy for Real-Time Bacterial Detection and Antibiotic Susceptibility Testing Using an Interdigitated Wave Electrode Array"],"prefix":"10.3390","volume":"26","author":[{"family":"Zeeshan","sequence":"first","affiliation":[{"name":"School of Computing, Gachon University, Seongnam-si 13120, Gyeonggi-do, Republic of Korea"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Naeem","family":"Iqbal","sequence":"additional","affiliation":[{"name":"Centre for Secure Information Technologies, Queen\u2019s University Belfast, Belfast BT3 9DT, UK"},{"name":"Momentum 1.0 Research, Queen\u2019s University Belfast, Belfast BT3 9DT, UK"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2026,8,6]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"48","DOI":"10.1038\/scientificamerican0518-48","article-title":"Global infections by the numbers","volume":"318","author":"Christiansen","year":"2018","journal-title":"Sci. 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