{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,10,12]],"date-time":"2025-10-12T03:49:53Z","timestamp":1760240993796,"version":"build-2065373602"},"reference-count":39,"publisher":"MDPI AG","issue":"21","license":[{"start":{"date-parts":[[2019,11,1]],"date-time":"2019-11-01T00:00:00Z","timestamp":1572566400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>Cantilever-based sensors have attracted considerable attention in the recent past due to their enormous and endless potential and possibilities coupled with their dynamic and unprecedented sensitivity in sensing applications. In this paper, we present a technique that involves depositing and vaporizing (at ambient conditions) a particle-laden water droplet onto a defined sensing area on in-house fabricated and commercial-based silicon microcantilever sensors. This process entailed the optimization of dispensing pressure and time to generate and realize a small water droplet volume (Vd = 49.7 \u00b1 1.9 pL). Moreover, we monitored the water evaporation trends on the sensing surface and observed total evaporation time per droplet of 39.0 \u00b1 1.8 s against a theoretically determined value of about 37.14 s. By using monodispersed particles in water, i.e., magnetic polystyrene particles (MPS) and polymethyl methacrylate (PMMA), and adsorbing them on a dynamic cantilever sensor, the mass and number of these particles were measured and determined comparatively using resonant frequency response measurements and SEM particle count analysis, respectively. As a result, we observed and reported monolayer particles assembled on the sensor with the lowest MPS particles count of about 19 \u00b1 2.<\/jats:p>","DOI":"10.3390\/s19214758","type":"journal-article","created":{"date-parts":[[2019,11,1]],"date-time":"2019-11-01T12:30:50Z","timestamp":1572611450000},"page":"4758","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":13,"title":["Cantilever-Droplet-Based Sensing of Magnetic Particle Concentrations in Liquids"],"prefix":"10.3390","volume":"19","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-3927-2439","authenticated-orcid":false,"given":"Wilson Ombati","family":"Nyang\u2019au","sequence":"first","affiliation":[{"name":"Institute of Semiconductor Technology (IHT) and Laboratory of Emerging Nanometrology (LENA), Technische Universit\u00e4t Braunschweig, 38106 Braunschweig, Germany"},{"name":"Department of Metrology, Kenya Bureau of Standards (KEBS), Nairobi 00200, Kenya"}]},{"given":"Andi","family":"Setiono","sequence":"additional","affiliation":[{"name":"Institute of Semiconductor Technology (IHT) and Laboratory of Emerging Nanometrology (LENA), Technische Universit\u00e4t Braunschweig, 38106 Braunschweig, Germany"},{"name":"Research Center for Physics, Indonesian Institute of Sciences (LIPI), Kawasan Puspiptek Serpong, 15314 Tangerang Selatan, Indonesia"}]},{"given":"Maik","family":"Bertke","sequence":"additional","affiliation":[{"name":"Institute of Semiconductor Technology (IHT) and Laboratory of Emerging Nanometrology (LENA), Technische Universit\u00e4t Braunschweig, 38106 Braunschweig, Germany"}]},{"given":"Harald","family":"Bosse","sequence":"additional","affiliation":[{"name":"Precision Engineering Division, Physikalisch-Technische Bundesanstalt (PTB), 38116 Braunschweig, Germany"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-5801-813X","authenticated-orcid":false,"given":"Erwin","family":"Peiner","sequence":"additional","affiliation":[{"name":"Institute of Semiconductor Technology (IHT) and Laboratory of Emerging Nanometrology (LENA), Technische Universit\u00e4t Braunschweig, 38106 Braunschweig, Germany"}]}],"member":"1968","published-online":{"date-parts":[[2019,11,1]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"449","DOI":"10.1557\/mrs2009.121","article-title":"Cantilever Sensors: Nanomechanical Tools for Diagnostics","volume":"34","author":"Datar","year":"2009","journal-title":"MRS Bull."},{"key":"ref_2","first-page":"36101","article-title":"Cantilever-like micromechanical sensors","volume":"74","author":"Boisen","year":"2011","journal-title":"J. Micromech. Microeng."},{"key":"ref_3","doi-asserted-by":"crossref","first-page":"28","DOI":"10.1016\/S1369-7021(08)70017-8","article-title":"Nanosensors for trace explosive detection","volume":"11","author":"Senesac","year":"2008","journal-title":"Mater. Today"},{"key":"ref_4","doi-asserted-by":"crossref","unstructured":"Setiono, A., Xu, J., Fahrbach, M., Bertke, M., Nyang\u2019au, W.O., Wasisto, H.S., and Peiner, E. (2019). Real-Time Frequency Tracking of an Electro-Thermal Piezoresistive Cantilever Resonator with ZnO Nanorods for Chemical Sensing. Chemosensors, 7.","DOI":"10.3390\/chemosensors7010002"},{"key":"ref_5","doi-asserted-by":"crossref","unstructured":"Hawe, A., Z\u00f6lls, S., Freitag, A., and Carpenter, J.F. (2015). Subvisible and Visible Particle Analysis in Biopharmaceutical Research and Development. Biophysical Characterization of Proteins in Developing Biopharmaceuticals, Elsevier.","DOI":"10.1016\/B978-0-444-59573-7.00010-5"},{"key":"ref_6","doi-asserted-by":"crossref","first-page":"1237","DOI":"10.1517\/17460440903386643","article-title":"Cantilever biosensors in drug discovery","volume":"4","author":"Xu","year":"2009","journal-title":"Expert Opin. Drug Discov."},{"key":"ref_7","doi-asserted-by":"crossref","first-page":"1068","DOI":"10.1002\/anie.200461910","article-title":"Multifunctional nanoparticles possessing a \u201cmagnetic motor effect\u201d for drug or gene delivery","volume":"44","author":"Yoon","year":"2005","journal-title":"Angew. Chem."},{"key":"ref_8","doi-asserted-by":"crossref","first-page":"e1800484","DOI":"10.1002\/adhm.201800484","article-title":"Recent Progress in Isolation and Detection of Extracellular Vesicles for Cancer Diagnostics","volume":"Volume 7","author":"Wang","year":"2018","journal-title":"Advanced Healthcare Materials"},{"key":"ref_9","doi-asserted-by":"crossref","first-page":"13452","DOI":"10.1038\/ncomms13452","article-title":"Mass and stiffness spectrometry of nanoparticles and whole intact bacteria by multimode nanomechanical resonators","volume":"7","author":"Malvar","year":"2016","journal-title":"Nat. Commun."},{"key":"ref_10","doi-asserted-by":"crossref","first-page":"1066","DOI":"10.1038\/nature05741","article-title":"Weighing of biomolecules, single cells and single nanoparticles in fluid","volume":"446","author":"Burg","year":"2007","journal-title":"Nature"},{"key":"ref_11","doi-asserted-by":"crossref","unstructured":"Alassi, A., Benammar, M., and Brett, D. (2017). Quartz Crystal Microbalance Electronic Interfacing Systems: A Review. Sensors, 17.","DOI":"10.3390\/s17122799"},{"key":"ref_12","doi-asserted-by":"crossref","first-page":"104","DOI":"10.1016\/j.jcis.2018.03.034","article-title":"Time-resolved viscoelastic properties of self-assembling iron oxide nanocube superlattices probed by quartz crystal microbalance with dissipation monitoring","volume":"522","author":"Kapuscinski","year":"2018","journal-title":"J. Colloid Interface Sci."},{"key":"ref_13","doi-asserted-by":"crossref","first-page":"49","DOI":"10.4283\/JKMS.2018.28.2.049","article-title":"Resonance Frequency Shift of Microcantilever via Surface Adsorption of Magnetic Nanoparticles","volume":"28","author":"Park","year":"2018","journal-title":"J. Korean Magn. Soc."},{"key":"ref_14","doi-asserted-by":"crossref","unstructured":"Ruffert, C. (2016). Magnetic Bead-Magic Bullet. Micromachines, 7.","DOI":"10.3390\/mi7020021"},{"key":"ref_15","first-page":"257","article-title":"The application of magnetic nanoparticles in the treatment and monitoring of cancer and infectious diseases","volume":"10","author":"Williams","year":"2017","journal-title":"Biosci. Horiz. Int. J. Stud. Res."},{"key":"ref_16","doi-asserted-by":"crossref","first-page":"928","DOI":"10.3389\/fmats.2019.00179","article-title":"A Comprehensive Review of Magnetic Nanomaterials Modern Day Theranostics","volume":"6","author":"Gul","year":"2019","journal-title":"Front. Mater."},{"key":"ref_17","doi-asserted-by":"crossref","first-page":"144","DOI":"10.1186\/1556-276X-7-144","article-title":"Magnetic nanoparticles: Preparation, physical properties, and applications in biomedicine","volume":"7","author":"Akbarzadeh","year":"2012","journal-title":"Nanoscale Res. Lett."},{"key":"ref_18","doi-asserted-by":"crossref","first-page":"5793","DOI":"10.1039\/C4CS00362D","article-title":"Industrial applications of nanoparticles","volume":"44","author":"Stark","year":"2015","journal-title":"Chem. Soc. Rev."},{"key":"ref_19","doi-asserted-by":"crossref","first-page":"14484","DOI":"10.1073\/pnas.1511443112","article-title":"Self-assembly of smallest magnetic particles","volume":"112","author":"Michaelis","year":"2015","journal-title":"Proc. Natl. Acad. Sci. USA"},{"key":"ref_20","first-page":"32","article-title":"Nanomaterial for High-Density Magnetic Data Storage","volume":"47","author":"Gubin","year":"2002","journal-title":"Russ. J. Inorg. Chem."},{"key":"ref_21","doi-asserted-by":"crossref","first-page":"1","DOI":"10.1016\/j.partic.2016.06.001","article-title":"Magnetic nanoparticles for environmental and biomedical applications: A review","volume":"30","author":"Mohammed","year":"2017","journal-title":"Particuology"},{"key":"ref_22","doi-asserted-by":"crossref","first-page":"10187","DOI":"10.1039\/C9TC03201K","article-title":"A novel material for the detection and removal of mercury(ii) based on a 2,6-bis(2-thienyl)pyridine receptor","volume":"7","author":"Egan","year":"2019","journal-title":"J. Mater. Chem. C"},{"key":"ref_23","doi-asserted-by":"crossref","first-page":"74","DOI":"10.1016\/j.mee.2017.04.030","article-title":"Towards fabrication of 3D isotopically modulated vertical silicon nanowires in selective areas by nanosphere lithography","volume":"179","author":"Hamdana","year":"2017","journal-title":"Microelectron. Eng."},{"key":"ref_24","doi-asserted-by":"crossref","unstructured":"Rueden, C.T., Schindelin, J., Hiner, M.C., DeZonia, B.E., Walter, A.E., Arena, E.T., and Eliceiri, K.W. (2017). ImageJ2: ImageJ for the next generation of scientific image data. BMC Bioinform., 18.","DOI":"10.1186\/s12859-017-1934-z"},{"key":"ref_25","doi-asserted-by":"crossref","first-page":"72","DOI":"10.1016\/j.colsurfa.2010.04.040","article-title":"Low-bond axisymmetric drop shape analysis for surface tension and contact angle measurements of sessile drops","volume":"364","author":"Stalder","year":"2010","journal-title":"Colloids Surf. A Physicochem. Eng. Asp."},{"key":"ref_26","doi-asserted-by":"crossref","first-page":"35010","DOI":"10.1088\/0960-1317\/24\/3\/035010","article-title":"The effects of oxygen plasma and humidity on surface roughness, water contact angle and hardness of silicon, silicon dioxide and glass","volume":"24","author":"Alam","year":"2014","journal-title":"J. Micromech. Microeng."},{"key":"ref_27","doi-asserted-by":"crossref","first-page":"96","DOI":"10.1016\/j.mee.2015.03.037","article-title":"Handheld personal airborne nanoparticle detector based on microelectromechanical silicon resonant cantilever","volume":"145","author":"Wasisto","year":"2015","journal-title":"Microelectron. Eng."},{"key":"ref_28","doi-asserted-by":"crossref","unstructured":"Bertke, M., Hamdana, G., Wu, W., Wasisto, H.S., Uhde, E., and Peiner, E. (2017). Analysis of asymmetric resonance response of thermally excited silicon micro-cantilevers for mass-sensitive nanoparticle detection. J. Micromech. Microeng., 27.","DOI":"10.1117\/12.2266084"},{"key":"ref_29","doi-asserted-by":"crossref","unstructured":"Schmid, S., Villanueva, L.G., and Roukes, M.L. (2016). Fundamentals of Nanomechanical Resonators, Springer International Publishing.","DOI":"10.1007\/978-3-319-28691-4"},{"key":"ref_30","doi-asserted-by":"crossref","first-page":"103303","DOI":"10.1063\/1.2804074","article-title":"Mass and position determination of attached particles on cantilever based mass sensors","volume":"78","author":"Dohn","year":"2007","journal-title":"Rev. Sci. Instrum."},{"key":"ref_31","doi-asserted-by":"crossref","unstructured":"Toledo, J., Ruiz-D\u00edez, V., Bertke, M., Suryo Wasisto, H., Peiner, E., and S\u00e1nchez-Rojas, J.L. (2019). Piezoelectric MEMS Resonators for Cigarette Particle Detection. Micromachines, 10.","DOI":"10.3390\/mi10020145"},{"key":"ref_32","doi-asserted-by":"crossref","first-page":"13020","DOI":"10.1021\/jp075714b","article-title":"Evaporation of femtoliter sessile droplets monitored with nanomechanical mass sensors","volume":"111","author":"Arcamone","year":"2007","journal-title":"J. Phys. Chem. B"},{"key":"ref_33","doi-asserted-by":"crossref","first-page":"2636","DOI":"10.1021\/la011470p","article-title":"Drop Evaporation on Solid Surfaces: Constant Contact Angle Mode","volume":"18","author":"Erbil","year":"2002","journal-title":"Langmuir"},{"key":"ref_34","doi-asserted-by":"crossref","unstructured":"Cussler, E.L. (2009). Diffusion. Mass Transfer in Fluid Systems, Cambridge University Press. [3rd ed.].","DOI":"10.1017\/CBO9780511805134"},{"key":"ref_35","doi-asserted-by":"crossref","unstructured":"Nyang\u2019au, W.O., Setiono, A., Puranto, P., Bertke, M., Wasisto, H.S., Viereck, T., Bosse, H., and Peiner, E. (2019, January 25\u201326). Droplet-on-cantilever approach for determining the mass of magnetic particles. Proceedings of the 20. GMA\/ITG-Fachtagung Sensoren und Messsysteme 2019, N\u00fcrnberg, Germany.","DOI":"10.5162\/sensoren2019\/3.2.1"},{"key":"ref_36","doi-asserted-by":"crossref","first-page":"2726","DOI":"10.1002\/cphc.201500410","article-title":"Manipulating the Coffee-Ring Effect: Interactions at Work","volume":"16","author":"Anyfantakis","year":"2015","journal-title":"Chemphyschem"},{"key":"ref_37","doi-asserted-by":"crossref","first-page":"980","DOI":"10.1016\/j.ultramic.2007.04.012","article-title":"Chemical patterns of octadecyltrimethoxysilane monolayers for the selective deposition of nanoparticles on silicon substrate","volume":"107","author":"Ressier","year":"2007","journal-title":"Ultramicroscopy"},{"key":"ref_38","doi-asserted-by":"crossref","unstructured":"Bertke, M., Xu, J., Fahrbach, M., Setiono, A., Wasisto, H.S., and Peiner, E. (2019). Strategy toward Miniaturized, Self-out-Readable Resonant Cantilever and Integrated Electrostatic Microchannel Separator for Highly Sensitive Airborne Nanoparticle Detection. Sensors, 19.","DOI":"10.3390\/s19040901"},{"key":"ref_39","unstructured":"Bertke, M., Xu, J., Setiono, A., Kirsch, I., Uhde, E., and Peiner, E. Fabrication of a micro-cantilever-based aerosol detector with integrated electrostatic on-chip ultrafine particle separation and collection. J. Micromech. Microeng., in press (accepted)."}],"container-title":["Sensors"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.mdpi.com\/1424-8220\/19\/21\/4758\/pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2025,10,11]],"date-time":"2025-10-11T13:31:20Z","timestamp":1760189480000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.mdpi.com\/1424-8220\/19\/21\/4758"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2019,11,1]]},"references-count":39,"journal-issue":{"issue":"21","published-online":{"date-parts":[[2019,11]]}},"alternative-id":["s19214758"],"URL":"https:\/\/doi.org\/10.3390\/s19214758","relation":{},"ISSN":["1424-8220"],"issn-type":[{"type":"electronic","value":"1424-8220"}],"subject":[],"published":{"date-parts":[[2019,11,1]]}}}