{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,10,26]],"date-time":"2025-10-26T21:20:02Z","timestamp":1761513602997,"version":"build-2065373602"},"reference-count":46,"publisher":"MDPI AG","issue":"3","license":[{"start":{"date-parts":[[2015,3,12]],"date-time":"2015-03-12T00:00:00Z","timestamp":1426118400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"RO1EB","award":["014586"],"award-info":[{"award-number":["014586"]}]},{"name":"TATRC W81XWH","award":["09-1-0711"],"award-info":[{"award-number":["09-1-0711"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>Integrated microfluidic devices with nanosized array electrodes and microfiltration capabilities can greatly increase sensitivity and enhance automation in immunoassay devices. In this contribution, we utilize the edge-patterning method of thin aluminum (Al) films in order to form nano- to micron-sized gaps. Evaporation of high work-function metals (i.e., Au, Ag, etc.) on these gaps, followed by Al lift-off, enables the formation of electrical uniform nanowires from low-cost, plastic-based, photomasks. By replacing Al with chromium (Cr), the formation of high resolution, custom-made photomasks that are ideal for low-cost fabrication of a plurality of array devices were realized. To demonstrate the feasibility of such Cr photomasks, SU-8 micro-pillar masters were formed and replicated into PDMS to produce micron-sized filters with 3\u20134 \u00b5m gaps and an aspect ratio of 3. These microfilters were capable of retaining 6 \u00b5m beads within a localized site, while allowing solvent flow. The combination of nanowire arrays and micro-pillar filtration opens new perspectives for  rapid R&amp;D screening of various microfluidic-based immunoassay geometries, where analyte pre-concentration and highly sensitive, electrochemical detection can be readily co-localized.<\/jats:p>","DOI":"10.3390\/s150306091","type":"journal-article","created":{"date-parts":[[2015,3,12]],"date-time":"2015-03-12T11:30:24Z","timestamp":1426159824000},"page":"6091-6104","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":7,"title":["Low-Cost Photolithographic Fabrication of Nanowires and Microfilters for Advanced Bioassay Devices"],"prefix":"10.3390","volume":"15","author":[{"given":"Nhi","family":"Doan","sequence":"first","affiliation":[{"name":"Nanomaterials Optoelectronics Laboratory, Polymer Program, University of Connecticut, Storrs, CT 06269, USA"}]},{"given":"Liangliang","family":"Qiang","sequence":"additional","affiliation":[{"name":"Nanomaterials Optoelectronics Laboratory, Polymer Program, University of Connecticut, Storrs, CT 06269, USA"}]},{"given":"Zhe","family":"Li","sequence":"additional","affiliation":[{"name":"Nanomaterials Optoelectronics Laboratory, Polymer Program, University of Connecticut, Storrs, CT 06269, USA"}]},{"given":"Santhisagar","family":"Vaddiraju","sequence":"additional","affiliation":[{"name":"Nanomaterials Optoelectronics Laboratory, Polymer Program, University of Connecticut, Storrs, CT 06269, USA"},{"name":"Biorasis Inc., 23 Fellen Road, Storrs, CT 06268, USA"}]},{"given":"Gregory","family":"Bishop","sequence":"additional","affiliation":[{"name":"Department of Chemistry, University of Connecticut, Storrs, CT 06269, USA"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-6117-3306","authenticated-orcid":false,"given":"James","family":"Rusling","sequence":"additional","affiliation":[{"name":"Department of Chemistry, University of Connecticut, Storrs, CT 06269, USA"},{"name":"Institute of Materials Science, University of Connecticut, Storrs, CT 06269, USA"},{"name":"Department of Cell Biology, University of Connecticut Health Center, Farmington, CT 062032, USA"},{"name":"School of Chemistry, National University of Ireland, Galway, Ireland"}]},{"given":"Fotios","family":"Papadimitrakopoulos","sequence":"additional","affiliation":[{"name":"Nanomaterials Optoelectronics Laboratory, Polymer Program, University of Connecticut, Storrs, CT 06269, USA"},{"name":"Department of Chemistry, University of Connecticut, Storrs, CT 06269, USA"},{"name":"Institute of Materials Science, University of Connecticut, Storrs, CT 06269, USA"}]}],"member":"1968","published-online":{"date-parts":[[2015,3,12]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"11","DOI":"10.1016\/j.aca.2003.09.019","article-title":"Integrated microfluidic devices","volume":"507","author":"Erickson","year":"2004","journal-title":"Anal. 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