{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,1,14]],"date-time":"2026-01-14T13:58:12Z","timestamp":1768399092405,"version":"3.49.0"},"reference-count":44,"publisher":"MDPI AG","issue":"11","license":[{"start":{"date-parts":[[2013,10,29]],"date-time":"2013-10-29T00:00:00Z","timestamp":1383004800000},"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>A microfluidic bioreactor with an easy to fabricate nano-plasmonic surface is demonstrated for studies of biofilms and their precursor materials via Surface Enhanced Raman Spectroscopy (SERS). The system uses a novel design to induce sheath flow confinement of a sodium citrate biofilm precursor stream against the SERS imaging surface to measure spatial variations in the concentration profile. The unoptimised SERS enhancement was approximately 2.5 \u00d7 104, thereby improving data acquisition time, reducing laser power requirements and enabling a citrate detection limit of 0.1 mM, which was well below the concentrations used in biofilm nutrient solutions. The flow confinement was observed by both optical microscopy and SERS imaging with good complementarity. We demonstrate the new bioreactor by growing flow-templated biofilms on the microchannel wall. This work opens the way for in situ spectral imaging of biofilms and their biochemical environment under dynamic flow conditions.<\/jats:p>","DOI":"10.3390\/s131114714","type":"journal-article","created":{"date-parts":[[2013,10,29]],"date-time":"2013-10-29T15:39:00Z","timestamp":1383061140000},"page":"14714-14727","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":22,"title":["A Microfluidic Bioreactor with in Situ SERS Imaging for the Study of Controlled Flow Patterns of Biofilm Precursor Materials"],"prefix":"10.3390","volume":"13","author":[{"given":"Fran\u00e7ois","family":"Paquet-Mercier","sequence":"first","affiliation":[{"name":"D\u00e9partement de Chimie, Universit\u00e9 Laval, 1045 Avenue de la M\u00e9decine, Qu\u00e9bec, QC G1V 0A6, Canada"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Nahid","family":"Aznaveh","sequence":"additional","affiliation":[{"name":"D\u00e9partement de Chimie, Universit\u00e9 Laval, 1045 Avenue de la M\u00e9decine, Qu\u00e9bec, QC G1V 0A6, Canada"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Muhammad","family":"Safdar","sequence":"additional","affiliation":[{"name":"D\u00e9partement de Chimie, Universit\u00e9 Laval, 1045 Avenue de la M\u00e9decine, Qu\u00e9bec, QC G1V 0A6, Canada"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-0880-9782","authenticated-orcid":false,"given":"Jesse","family":"Greener","sequence":"additional","affiliation":[{"name":"D\u00e9partement de Chimie, Universit\u00e9 Laval, 1045 Avenue de la M\u00e9decine, Qu\u00e9bec, QC G1V 0A6, Canada"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2013,10,29]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"550","DOI":"10.1002\/(SICI)1521-3773(19980316)37:5<550::AID-ANIE550>3.0.CO;2-G","article-title":"Soft lithography","volume":"37","author":"Xia","year":"1998","journal-title":"Angew. 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