{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,6,26]],"date-time":"2026-06-26T18:38:43Z","timestamp":1782499123405,"version":"3.54.5"},"reference-count":42,"publisher":"MDPI AG","issue":"15","license":[{"start":{"date-parts":[[2021,7,21]],"date-time":"2021-07-21T00:00:00Z","timestamp":1626825600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Geran Universiti Penyelidikan","award":["GUP-2020-071"],"award-info":[{"award-number":["GUP-2020-071"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>We present the integration of a flow focusing microfluidic device in a dielectrophoretic application that based on a tapered aluminum microelectrode array (TAMA). The characterization and optimization method of microfluidic geometry performs the hydrodynamic flow focusing on the channel. The sample fluids are hydrodynamically focused into the region of interest (ROI) where the dielectrophoresis force (FDEP) is dominant. The device geometry is designed using 3D CAD software and fabricated using the micro-milling process combined with soft lithography using PDMS. The flow simulation is achieved using COMSOL Multiphysics 5.5 to study the effect of the flow rate ratio between the sample fluids (Q1) and the sheath fluids (Q2) toward the width of flow focusing. Five different flow rate ratios (Q1\/Q2) are recorded in this experiment, which are 0.2, 0.4, 0.6, 0.8 and 1.0. The width of flow focusing is increased linearly with the flow rate ratio (Q1\/Q2) for both the simulation and the experiment. At the highest flow rate ratio (Q1\/Q2 = 1), the width of flow focusing is obtained at 638.66 \u00b5m and at the lowest flow rate ratio (Q1\/Q2 = 0.2), the width of flow focusing is obtained at 226.03 \u00b5m. As a result, the flow focusing effect is able to reduce the dispersion of the particles in the microelectrode from 2000 \u00b5m to 226.03 \u00b5m toward the ROI. The significance of flow focusing on the separation of particles is studied using 10 and 1 \u00b5m polystyrene beads by applying a non-uniform electrical field to the TAMA at 10 VPP, 150 kHz. Ultimately, we are able to manipulate the trajectories of two different types of particles in the channel. For further validation, the focusing of 3.2 \u00b5m polystyrene beads within the dominant FDEP results in an enhanced manipulation efficiency from 20% to 80% in the ROI.<\/jats:p>","DOI":"10.3390\/s21154957","type":"journal-article","created":{"date-parts":[[2021,7,22]],"date-time":"2021-07-22T22:37:14Z","timestamp":1626993434000},"page":"4957","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":10,"title":["Integration of a Dielectrophoretic Tapered Aluminum Microelectrode Array with a Flow Focusing Technique"],"prefix":"10.3390","volume":"21","author":[{"ORCID":"https:\/\/orcid.org\/0000-0001-6181-5498","authenticated-orcid":false,"given":"Naqib Fuad Abd","family":"Rashid","sequence":"first","affiliation":[{"name":"Institute of Microengineering and Nanoelectronics (IMEN), Universiti Kebangsaan Malaysia (UKM), Bangi 43600, Selangor, Malaysia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-0001-1864","authenticated-orcid":false,"given":"Revathy","family":"Deivasigamani","sequence":"additional","affiliation":[{"name":"Institute of Microengineering and Nanoelectronics (IMEN), Universiti Kebangsaan Malaysia (UKM), Bangi 43600, Selangor, Malaysia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-5543-2300","authenticated-orcid":false,"given":"M. F. Mohd Razip","family":"Wee","sequence":"additional","affiliation":[{"name":"Institute of Microengineering and Nanoelectronics (IMEN), Universiti Kebangsaan Malaysia (UKM), Bangi 43600, Selangor, Malaysia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-8916-4420","authenticated-orcid":false,"given":"Azrul Azlan","family":"Hamzah","sequence":"additional","affiliation":[{"name":"Institute of Microengineering and Nanoelectronics (IMEN), Universiti Kebangsaan Malaysia (UKM), Bangi 43600, Selangor, Malaysia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-4104-5320","authenticated-orcid":false,"given":"Muhamad Ramdzan","family":"Buyong","sequence":"additional","affiliation":[{"name":"Institute of Microengineering and Nanoelectronics (IMEN), Universiti Kebangsaan Malaysia (UKM), Bangi 43600, Selangor, Malaysia"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2021,7,21]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"021501","DOI":"10.1063\/1.4799787","article-title":"Hydrodynamic mechanisms of cell and particle trapping in microfluidics","volume":"7","author":"Karimi","year":"2013","journal-title":"Biomicrofluidics"},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"27","DOI":"10.1049\/iet-nbt:20060021","article-title":"Oxygen adsorption by carbon nanotubes and its application in radiotherapy","volume":"1","author":"Sieben","year":"2007","journal-title":"IET Nanobiotechnol."},{"key":"ref_3","doi-asserted-by":"crossref","first-page":"987","DOI":"10.1126\/science.1094567","article-title":"Continuous Particle Separation Through Deterministic Lateral Displacement","volume":"304","author":"Huang","year":"2004","journal-title":"Science"},{"key":"ref_4","doi-asserted-by":"crossref","first-page":"1","DOI":"10.1038\/s41598-020-68699-4","article-title":"Parametric study on the geometrical parameters of a lab-on-a-chip platform with tilted planar electrodes for continuous dielectrophoretic manipulation of microparticles","volume":"10","author":"Dalili","year":"2020","journal-title":"Sci. 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