{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,2,20]],"date-time":"2026-02-20T18:35:58Z","timestamp":1771612558974,"version":"3.50.1"},"reference-count":37,"publisher":"MDPI AG","issue":"10","license":[{"start":{"date-parts":[[2025,5,17]],"date-time":"2025-05-17T00:00:00Z","timestamp":1747440000000},"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>We present a compact and cost-effective real-time PCR system designed for point-of-care testing (POCT), utilizing a PCB-based disposable chip and an open-platform CMOS camera. The system integrates precise thermal cycling with software-synchronized fluorescence detection and provides real-time analysis through a dedicated user interface. To minimize cost and complexity, a polycarbonate reaction chamber was integrated with a PCB-based heater and thermistor. A slanted LED illumination setup and an open-platform USB camera were employed for fluorescence imaging. Signal alignment was enhanced using device-specific region-of-interest (ROI) tracking based on copper pad corner detection. Thermal cycling performance achieved a heating rate of 8.0 \u00b0C\/s and a cooling rate of \u22129.3 \u00b0C\/s, with steady-state accuracy within \u00b10.1 \u00b0C. Fluorescence images exhibited high dynamic range without saturation, and the 3\u03c3-based ROI correction method improved signal reliability. System performance was validated using Chlamydia trachomatis DNA standard (103 copies), yielding consistent amplification curves with a Ct standard deviation below 0.3 cycles. These results demonstrate that the proposed system enables rapid, accurate, and reproducible nucleic acid detection, making it a strong candidate for field-deployable molecular diagnostics.<\/jats:p>","DOI":"10.3390\/s25103159","type":"journal-article","created":{"date-parts":[[2025,5,19]],"date-time":"2025-05-19T05:37:13Z","timestamp":1747633033000},"page":"3159","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":2,"title":["A Compact Real-Time PCR System for Point-of-Care Detection Using a PCB-Based Disposable Chip and Open-Platform CMOS Camera"],"prefix":"10.3390","volume":"25","author":[{"given":"MinGin","family":"Kim","sequence":"first","affiliation":[{"name":"Thermo Fisher Scientific, South San Francisco, CA 94080, USA"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Sung-Hun","family":"Yun","sequence":"additional","affiliation":[{"name":"School of Software, Hallym University, Chuncheon-si 24252, Republic of Korea"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Sun-Hee","family":"Kim","sequence":"additional","affiliation":[{"name":"Department of Fashion Industry, Incheon National University, Incheon 22012, Republic of Korea"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Jong-Dae","family":"Kim","sequence":"additional","affiliation":[{"name":"School of Software, Hallym University, Chuncheon-si 24252, Republic of Korea"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2025,5,17]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"1047","DOI":"10.1089\/cmb.2005.12.1047","article-title":"Comprehensive Algorithm for Quantitative Real-Time Polymerase Chain Reaction","volume":"12","author":"Zhao","year":"2005","journal-title":"J. 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