{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,6,2]],"date-time":"2026-06-02T07:44:53Z","timestamp":1780386293895,"version":"3.54.1"},"reference-count":22,"publisher":"MDPI AG","issue":"5","license":[{"start":{"date-parts":[[2016,5,2]],"date-time":"2016-05-02T00:00:00Z","timestamp":1462147200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Micromachines"],"abstract":"<jats:p>This work demonstrates the fabrication of microfluidic paper-based analytical devices (\u00b5PADs) suitable for the analysis of sub-microliter sample volumes. The wax-printing approach widely used for the patterning of paper substrates has been adapted to obtain high-resolution microfluidic structures patterned in filter paper. This has been achieved by replacing the hot plate heating method conventionally used to melt printed wax features into paper by simple hot lamination. This patterning technique, in combination with the consideration of device geometry and the influence of cellulose fiber direction in filter paper, led to a model \u00b5PAD design with four microfluidic channels that can be filled with as low as 0.5 \u00b5L of liquid. Finally, the application to a colorimetric model assay targeting total protein concentrations is shown. Calibration curves for human serum albumin (HSA) were recorded from sub-microliter samples (0.8 \u00b5L), with tolerance against \u00b10.1 \u00b5L variations in the applied liquid volume.<\/jats:p>","DOI":"10.3390\/mi7050080","type":"journal-article","created":{"date-parts":[[2016,5,2]],"date-time":"2016-05-02T10:17:11Z","timestamp":1462184231000},"page":"80","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":76,"title":["High-Resolution Microfluidic Paper-Based Analytical Devices for Sub-Microliter Sample Analysis"],"prefix":"10.3390","volume":"7","author":[{"given":"Keisuke","family":"Tenda","sequence":"first","affiliation":[{"name":"Department of Applied Chemistry, Keio University, 3-14-1 Hiyoshi, Kohoku-ku, Yokohama 223-8522, Kanagawa, Japan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Riki","family":"Ota","sequence":"additional","affiliation":[{"name":"Department of Applied Chemistry, Keio University, 3-14-1 Hiyoshi, Kohoku-ku, Yokohama 223-8522, Kanagawa, Japan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Kentaro","family":"Yamada","sequence":"additional","affiliation":[{"name":"Department of Applied Chemistry, Keio University, 3-14-1 Hiyoshi, Kohoku-ku, Yokohama 223-8522, Kanagawa, Japan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Terence","family":"Henares","sequence":"additional","affiliation":[{"name":"Department of Applied Chemistry, Keio University, 3-14-1 Hiyoshi, Kohoku-ku, Yokohama 223-8522, Kanagawa, Japan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Koji","family":"Suzuki","sequence":"additional","affiliation":[{"name":"Department of Applied Chemistry, Keio University, 3-14-1 Hiyoshi, Kohoku-ku, Yokohama 223-8522, Kanagawa, Japan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-7420-045X","authenticated-orcid":false,"given":"Daniel","family":"Citterio","sequence":"additional","affiliation":[{"name":"Department of Applied Chemistry, Keio University, 3-14-1 Hiyoshi, Kohoku-ku, Yokohama 223-8522, Kanagawa, Japan"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2016,5,2]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"774","DOI":"10.1016\/j.bios.2015.10.032","article-title":"Fabrication techniques for microfluidic paper-based analytical devices and their applications for biological testing: A review","volume":"77","author":"Xia","year":"2016","journal-title":"Biosens. Bioelectron."},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"19","DOI":"10.1021\/ac503968p","article-title":"Recent Developments in Paper-Based Microfluidic Devices","volume":"87","author":"Cate","year":"2015","journal-title":"Anal. Chem."},{"key":"ref_3","doi-asserted-by":"crossref","first-page":"5294","DOI":"10.1002\/anie.201411508","article-title":"Paper-Based Inkjet-Printed Microfluidic Analytical Devices","volume":"54","author":"Yamada","year":"2015","journal-title":"Angew. Chem. Int. Ed."},{"key":"ref_4","doi-asserted-by":"crossref","first-page":"78109","DOI":"10.1039\/C5RA09188H","article-title":"Fabrication of paper-based microfluidic analysis devices: A review","volume":"5","author":"He","year":"2015","journal-title":"RSC Adv."},{"key":"ref_5","doi-asserted-by":"crossref","first-page":"249","DOI":"10.1016\/j.bios.2015.09.038","article-title":"Paper-based chemical and biological sensors: Engineering aspects","volume":"77","author":"Ahmed","year":"2016","journal-title":"Biosens. Bioelectron."},{"key":"ref_6","doi-asserted-by":"crossref","first-page":"2210","DOI":"10.1039\/c3lc50169h","article-title":"Paper-based microfluidic point-of-care diagnostic devices","volume":"13","author":"Yetisen","year":"2013","journal-title":"Lab Chip"},{"key":"ref_7","doi-asserted-by":"crossref","first-page":"04DL02","DOI":"10.1143\/JJAP.51.04DL02","article-title":"Sub-micro-liter electrochemical single-nucleotide-polymorphism setector for lab-on-chip system","volume":"51","author":"Tanaka","year":"2012","journal-title":"Jpn. J. Appl. Phys."},{"key":"ref_8","doi-asserted-by":"crossref","first-page":"035027","DOI":"10.1088\/0960-1317\/19\/3\/035027","article-title":"Pneumatically driven micro-dispenser for sub-micro-liter pipetting","volume":"19","author":"Huang","year":"2009","journal-title":"J. Micromech. Microeng."},{"key":"ref_9","doi-asserted-by":"crossref","first-page":"2756","DOI":"10.1021\/ac062179n","article-title":"Using a multijunction microfluidic device to inject substrate into an array of preformed plugs without cross-contamination: comparing theory and experiments","volume":"79","author":"Li","year":"2007","journal-title":"Anal. Chem."},{"key":"ref_10","doi-asserted-by":"crossref","first-page":"1637","DOI":"10.1039\/c3an01926h","article-title":"An antibody-free microfluidic paper-based analytical device for the determination of tear fluid lactoferrin by fluorescence sensitization of Tb3+","volume":"139","author":"Yamada","year":"2014","journal-title":"Analyst"},{"key":"ref_11","doi-asserted-by":"crossref","unstructured":"Jain, S., Rajasingham, R., Noubary, F., Coonahan, E., Schoeplein, R., Baden, R., Curry, M., Afdhal, N., Kumar, S., and Pollock, N.R. (2015). Performance of an Optimized Paper-Based Test for Rapid Visual Measurement of Alanine Aminotransferase (ALT) in Fingerstick and Venipuncture Samples. PLOS ONE, 10.","DOI":"10.1371\/journal.pone.0128118"},{"key":"ref_12","doi-asserted-by":"crossref","first-page":"1318","DOI":"10.1002\/anie.200603817","article-title":"Patterned paper as a platform for inexpensive, low-volume, portable bioassays","volume":"46","author":"Martinez","year":"2007","journal-title":"Angew. Chem. Int. Ed."},{"key":"ref_13","doi-asserted-by":"crossref","first-page":"7091","DOI":"10.1021\/ac901071p","article-title":"Understanding wax printing: a simple micropatterning process for paper-based microfluidics","volume":"81","author":"Carrilho","year":"2009","journal-title":"Anal. Chem."},{"key":"ref_14","doi-asserted-by":"crossref","first-page":"1497","DOI":"10.1002\/elps.200800563","article-title":"Rapid prototyping of paper-based microfluidics with wax for low-cost, portable bioassay","volume":"30","author":"Lu","year":"2009","journal-title":"Electrophoresis"},{"key":"ref_15","doi-asserted-by":"crossref","first-page":"1188","DOI":"10.1039\/C4LC01382D","article-title":"Toward instrument-free digital measurements: A three-dimensional microfluidic device fabricated in a single sheet of paper by double-sided printing and lamination","volume":"15","author":"Jeong","year":"2015","journal-title":"Lab Chip"},{"key":"ref_16","doi-asserted-by":"crossref","first-page":"55633","DOI":"10.1039\/C5RA06479A","article-title":"Measurement of total antioxidant capacity in sub-\u03bcL blood samples using craft paper-based analytical devices","volume":"5","author":"Sun","year":"2015","journal-title":"RSC Adv."},{"key":"ref_17","doi-asserted-by":"crossref","first-page":"925","DOI":"10.1039\/C5LC01365H","article-title":"Sample pre-concentration with high enrichment factors at a fixed location in paper-based microfluidic devices","volume":"16","author":"Yeh","year":"2016","journal-title":"Lab Chip"},{"key":"ref_18","doi-asserted-by":"crossref","first-page":"381","DOI":"10.1134\/S0006297908040020","article-title":"Tear proteins in health, disease, and contact lens wear","volume":"73","author":"Sariri","year":"2008","journal-title":"Biochem. Mosc."},{"key":"ref_19","doi-asserted-by":"crossref","unstructured":"Rantam\u00e4ki, A.H., Sepp\u00e4nen-Laakso, T., Oresic, M., Jauhiainen, M., and Holopainen, J.M. (2011). Human tear fluid lipidome: from composition to function. PLOS ONE, 6.","DOI":"10.1371\/journal.pone.0019553"},{"key":"ref_20","doi-asserted-by":"crossref","first-page":"12867","DOI":"10.1039\/C4RA00434E","article-title":"Paper substrate modification for rapid capillary flow in microfluidic paper-based analytical devices","volume":"4","author":"Xu","year":"2014","journal-title":"RSC Adv."},{"key":"ref_21","doi-asserted-by":"crossref","first-page":"83","DOI":"10.2116\/analsci.21.83","article-title":"Theoretical analysis concerning the characteristics of a dye-binding method for determining serum protein based on protein error of pH indicator: effect of buffer concentration of the color reagent on the color development","volume":"21","author":"Suzuki","year":"2005","journal-title":"Anal. Sci."},{"key":"ref_22","doi-asserted-by":"crossref","first-page":"400","DOI":"10.47102\/annals-acadmedsg.V35N6p400","article-title":"Characterisation of human tear proteins using high-resolution mass spectrometry","volume":"35","author":"Zhou","year":"2006","journal-title":"Ann. Acad. Med. Singap."}],"container-title":["Micromachines"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.mdpi.com\/2072-666X\/7\/5\/80\/pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2025,10,11]],"date-time":"2025-10-11T19:23:11Z","timestamp":1760210591000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.mdpi.com\/2072-666X\/7\/5\/80"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2016,5,2]]},"references-count":22,"journal-issue":{"issue":"5","published-online":{"date-parts":[[2016,5]]}},"alternative-id":["mi7050080"],"URL":"https:\/\/doi.org\/10.3390\/mi7050080","relation":{},"ISSN":["2072-666X"],"issn-type":[{"value":"2072-666X","type":"electronic"}],"subject":[],"published":{"date-parts":[[2016,5,2]]}}}