{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,10,16]],"date-time":"2025-10-16T20:16:09Z","timestamp":1760645769359,"version":"build-2065373602"},"reference-count":18,"publisher":"MDPI AG","issue":"7","license":[{"start":{"date-parts":[[2010,7,12]],"date-time":"2010-07-12T00:00:00Z","timestamp":1278892800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/3.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>Optical fluorescence and absorption are two of the primary techniques used for analytical microfluidics. We provide a thorough yet tractable method for computing the performance of diverse optical micro-analytical systems. Sample sizes range from nano- to many micro-liters and concentrations from nano- to milli-molar. Equations are provided to trace quantitatively the flow of the fundamental entities, namely photons and electrons, and the conversion of energy from the source, through optical components, samples and spectral-selective components, to the detectors and beyond. The equations permit facile computations of calibration curves that relate the concentrations or numbers of molecules measured to the absolute signals from the system. This methodology provides the basis for both detailed understanding and improved design of microfluidic optical analytical systems. It saves prototype turn-around time, and is much simpler and faster to use than ray tracing programs. Over two thousand spreadsheet computations were performed during this study. We found that some design variations produce higher signal levels and, for constant noise levels, lower minimum detection limits. Improvements of more than a factor of 1,000 were realized.<\/jats:p>","DOI":"10.3390\/s100706730","type":"journal-article","created":{"date-parts":[[2010,7,12]],"date-time":"2010-07-12T11:37:07Z","timestamp":1278934627000},"page":"6730-6750","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":1,"title":["Computational Methodology for Absolute Calibration Curves for Microfluidic Optical Analyses"],"prefix":"10.3390","volume":"10","author":[{"given":"Chia-Pin","family":"Chang","sequence":"first","affiliation":[{"name":"Department of Electrical and Computer Engineering, The George Washington University, Washington DC 20052, USA"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"David J.","family":"Nagel","sequence":"additional","affiliation":[{"name":"Department of Electrical and Computer Engineering, The George Washington University, Washington DC 20052, USA"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Mona E.","family":"Zaghloul","sequence":"additional","affiliation":[{"name":"Department of Electrical and Computer Engineering, The George Washington University, Washington DC 20052, USA"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2010,7,12]]},"reference":[{"key":"ref_1","unstructured":"Nguyen, NT, and Wereley, ST (2006). Fundamentals and Applications of Microfluidics, Artech House."},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"71","DOI":"10.1023\/A:1009986407026","article-title":"Toward next generation clinical diagnostic instruments: scaling and new processing paradigms","volume":"1","author":"Petersen","year":"1998","journal-title":"Biomed. Microdev"},{"key":"ref_3","doi-asserted-by":"crossref","first-page":"71","DOI":"10.1007\/s00216-003-2060-5","article-title":"Sensor strategies for microorganism detection\u2014From physical principles to imprinting procedures","volume":"377","author":"Dickert","year":"2003","journal-title":"Anal. Bioanal. 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Optical Biosensors: Today and Tomorrow, Elsevier Science Ltd."},{"key":"ref_8","doi-asserted-by":"crossref","first-page":"955","DOI":"10.1039\/b704008c","article-title":"Optical filtering technologies for integrated fluorescence sensors","volume":"7","author":"Dandin","year":"2007","journal-title":"Lab. Chip"},{"key":"ref_9","unstructured":"Luminous Efficacy. Available online: http:\/\/hyperphysics.phy-astr.gsu.edu\/hbase\/vision\/efficacy.html (accessed on 27 April 2010)."},{"key":"ref_10","unstructured":"Molar absorption coefficient. 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Chim. Acta"},{"key":"ref_15","doi-asserted-by":"crossref","first-page":"4491","DOI":"10.1021\/ac010423z","article-title":"An integrated fluorescence detection system in poly(dimethylsiloxane) for microfluidic applications","volume":"73","author":"Chabinyc","year":"2001","journal-title":"Anal. Chem"},{"key":"ref_16","doi-asserted-by":"crossref","first-page":"1","DOI":"10.1016\/j.sna.2003.10.015","article-title":"Heterogeneous integration of CdS filters with GaN LEDs for fluorescence detection microsystems","volume":"111","author":"Chediak","year":"2004","journal-title":"Sensor. Actuator-A"},{"key":"ref_17","doi-asserted-by":"crossref","first-page":"5300","DOI":"10.1021\/ac0301550","article-title":"Integrated hydrogenated amorphous Si photodiode detector for microfluidic bioanalytical devices","volume":"75","author":"Kamei","year":"2003","journal-title":"Anal. Chem"},{"key":"ref_18","doi-asserted-by":"crossref","first-page":"17","DOI":"10.1109\/MPOT.2008.929294","article-title":"Go with the (micro) flow","volume":"27","author":"Chang","year":"2008","journal-title":"IEEE Potentials"}],"container-title":["Sensors"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.mdpi.com\/1424-8220\/10\/7\/6730\/pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2025,10,11]],"date-time":"2025-10-11T22:02:54Z","timestamp":1760220174000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.mdpi.com\/1424-8220\/10\/7\/6730"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2010,7,12]]},"references-count":18,"journal-issue":{"issue":"7","published-online":{"date-parts":[[2010,7]]}},"alternative-id":["s100706730"],"URL":"https:\/\/doi.org\/10.3390\/s100706730","relation":{},"ISSN":["1424-8220"],"issn-type":[{"type":"electronic","value":"1424-8220"}],"subject":[],"published":{"date-parts":[[2010,7,12]]}}}