{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,5,14]],"date-time":"2026-05-14T15:58:35Z","timestamp":1778774315137,"version":"3.51.4"},"reference-count":27,"publisher":"AIP Publishing","issue":"1","license":[{"start":{"date-parts":[[2017,12,29]],"date-time":"2017-12-29T00:00:00Z","timestamp":1514505600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"},{"start":{"date-parts":[[2017,12,29]],"date-time":"2017-12-29T00:00:00Z","timestamp":1514505600000},"content-version":"tdm","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Swedish Infrastructure for Micro- and Nanofabrication - Myfab"},{"DOI":"10.13039\/501100004063","name":"Knut och Alice Wallenbergs Stiftelse","doi-asserted-by":"publisher","id":[{"id":"10.13039\/501100004063","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100001729","name":"Stiftelsen f\u00f6r\u00a0Strategisk Forskning","doi-asserted-by":"publisher","award":["#SBE13-0125"],"award-info":[{"award-number":["#SBE13-0125"]}],"id":[{"id":"10.13039\/501100001729","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":["pubs.aip.org"],"crossmark-restriction":true},"short-container-title":[],"published-print":{"date-parts":[[2018,3,1]]},"abstract":"<jats:p>A bioassay based on a high-Tc superconducting quantum interference device (SQUID) reading out functionalized magnetic nanoparticles (fMNPs) in a prototype microfluidic platform is presented. The target molecule recognition is based on volume amplification using padlock-probe-ligation followed by rolling circle amplification (RCA). The MNPs are functionalized with single-stranded oligonucleotides, which give a specific binding of the MNPs to the large RCA coil product, resulting in a large change in the amplitude of the imaginary part of the ac magnetic susceptibility. The RCA products from amplification of synthetic Vibrio cholera target DNA were investigated using our SQUID ac susceptibility system in microfluidic channel with an equivalent sample volume of 3\u2009\u03bcl. From extrapolation of the linear dependence of the SQUID signal versus concentration of the RCA coils, it is found that the projected limit of detection for our system is about 1.0\u2009\u00d7\u2009105 RCA coils (0.2 \u00d7 10\u221218 mol), which is equivalent to 66 fM in the 3\u2009\u03bcl sample volume. This ultra-high magnetic sensitivity and integration with microfluidic sample handling are critical steps towards magnetic bioassays for rapid detection of DNA and RNA targets at the point of care.<\/jats:p>","DOI":"10.1063\/1.4999713","type":"journal-article","created":{"date-parts":[[2017,12,29]],"date-time":"2017-12-29T15:18:42Z","timestamp":1514560722000},"update-policy":"https:\/\/doi.org\/10.1063\/aip-crossmark-policy-page","source":"Crossref","is-referenced-by-count":14,"title":["Volume-amplified magnetic bioassay integrated with microfluidic sample handling and high-<i>Tc<\/i> SQUID magnetic readout"],"prefix":"10.1063","volume":"2","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-2145-1340","authenticated-orcid":false,"given":"Sobhan","family":"Sepehri","sequence":"first","affiliation":[{"name":"Department of Microtechnology and Nanoscience\u2013MC2, Chalmers University of Technology 1 , G\u00f6teborg 412 96, Sweden"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Emil","family":"Eriksson","sequence":"additional","affiliation":[{"name":"RISE Acreo AB 2 , SE-411 33 G\u00f6teborg, Sweden"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Alexei","family":"Kalaboukhov","sequence":"additional","affiliation":[{"name":"Department of Microtechnology and Nanoscience\u2013MC2, Chalmers University of Technology 1 , G\u00f6teborg 412 96, Sweden"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Teresa","family":"Zard\u00e1n G\u00f3mez de la Torre","sequence":"additional","affiliation":[{"name":"Department of Engineering Sciences, Uppsala University 3 , The \u00c5ngstr\u00f6m Laboratory, Box 534, SE-751 21 Uppsala, Sweden"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Kiryl","family":"Kustanovich","sequence":"additional","affiliation":[{"name":"Department of Chemistry and Chemical Engineering, Chalmers University of Technology 4 , G\u00f6teborg 412 96, Sweden"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Aldo","family":"Jesorka","sequence":"additional","affiliation":[{"name":"Department of Chemistry and Chemical Engineering, Chalmers University of Technology 4 , G\u00f6teborg 412 96, Sweden"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Justin F.","family":"Schneiderman","sequence":"additional","affiliation":[{"name":"Department of Microtechnology and Nanoscience\u2013MC2, Chalmers University of Technology 1 , G\u00f6teborg 412 96, Sweden"},{"name":"MedTech West and the Institute of Neuroscience and Physiology, University of Gothenburg 5 , SE-40530 G\u00f6teborg, Sweden"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Jakob","family":"Blomgren","sequence":"additional","affiliation":[{"name":"RISE Acreo AB 2 , SE-411 33 G\u00f6teborg, Sweden"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Christer","family":"Johansson","sequence":"additional","affiliation":[{"name":"RISE Acreo AB 2 , SE-411 33 G\u00f6teborg, Sweden"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Maria","family":"Str\u00f8mme","sequence":"additional","affiliation":[{"name":"Department of Engineering Sciences, Uppsala University 3 , The \u00c5ngstr\u00f6m Laboratory, Box 534, SE-751 21 Uppsala, Sweden"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-8332-3742","authenticated-orcid":false,"given":"Dag","family":"Winkler","sequence":"additional","affiliation":[{"name":"Department of Microtechnology and Nanoscience\u2013MC2, Chalmers University of Technology 1 , G\u00f6teborg 412 96, Sweden"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"317","published-online":{"date-parts":[[2017,12,29]]},"reference":[{"key":"2024031517020149600_c1","doi-asserted-by":"publisher","first-page":"14","DOI":"10.1016\/j.jmmm.2016.10.041","article-title":"Sensitive magnetic biodetection using magnetic multi-core nanoparticles and RCA coils","volume":"427","year":"2016","journal-title":"J. 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