{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,4,8]],"date-time":"2026-04-08T10:44:31Z","timestamp":1775645071761,"version":"3.50.1"},"reference-count":45,"publisher":"MDPI AG","issue":"21","license":[{"start":{"date-parts":[[2022,10,26]],"date-time":"2022-10-26T00:00:00Z","timestamp":1666742400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Ministry of Higher Education of Malaysia","award":["FRGS\/1\/2021\/TK0\/UKM\/02\/29"],"award-info":[{"award-number":["FRGS\/1\/2021\/TK0\/UKM\/02\/29"]}]},{"name":"Ministry of Higher Education of Malaysia","award":["GUP-2022-006"],"award-info":[{"award-number":["GUP-2022-006"]}]},{"name":"Universiti Kebangsaan Malaysia","award":["FRGS\/1\/2021\/TK0\/UKM\/02\/29"],"award-info":[{"award-number":["FRGS\/1\/2021\/TK0\/UKM\/02\/29"]}]},{"name":"Universiti Kebangsaan Malaysia","award":["GUP-2022-006"],"award-info":[{"award-number":["GUP-2022-006"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>A thin film of single-walled carbon nanotube (SWCNT) network field-effect transistor (FET) was fabricated by a simple, fast, and reliable deposition method for electronic applications. This study aims to develop a method for fabricating a thin film of random SWCNTs to be used as a transducer to detect human serum albumin (HSA) in biosensor applications. The random SWCNT network was deposited using the airbrush technique. The morphology of the CNT network was examined by utilising atomic force microscopy (AFM) and field-emission scanning electron microscopy (FESEM), while electrical characteristics were analysed using three-terminal IV measurements. The thin film (SWCNT network) was applied as a transducer to detect human serum albumin (HSA) based on its covalent interaction with antibodies. HSA plays a significant part in the physiological functions of the human body. The surface alteration of the SWCNTs was verified using Fourier transform infrared (FTIR) spectroscopy. Electrical current\u2013voltage measurements validated the surface binding and HSA detection. The biosensor linearly recorded a 0.47 fg\/mL limit of detection (LOD) and a high sensitivity of 3.44 \u03bcA (g\/mL)\u22121 between 1 fg\/mL and 10 pg\/mL. This device can also be used to identify a genuine HSA despite interference from other biomolecules (i.e., bovine serum albumin (BSA)), thus demonstrating the random SWCNT-FET immunosensor ability to quantify HSA in a complex biological environment.<\/jats:p>","DOI":"10.3390\/s22218212","type":"journal-article","created":{"date-parts":[[2022,10,26]],"date-time":"2022-10-26T09:59:37Z","timestamp":1666778377000},"page":"8212","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":8,"title":["SWCNT Network-FET Device for Human Serum Albumin Detection"],"prefix":"10.3390","volume":"22","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-1839-500X","authenticated-orcid":false,"given":"Iskandar","family":"Yahya","sequence":"first","affiliation":[{"name":"Faculty of Engineering & Built Environment, National University of Malaysia (UKM), Bangi 43600, Malaysia"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Muhamad Azuddin","family":"Hassan","sequence":"additional","affiliation":[{"name":"Institute of Microengineering and Nanoelectronics (IMEN), National University of Malaysia (UKM), Bangi 43600, Malaysia"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-1269-2131","authenticated-orcid":false,"given":"Nur Nasyifa Mohd","family":"Maidin","sequence":"additional","affiliation":[{"name":"Institute of Microengineering and Nanoelectronics (IMEN), National University of Malaysia (UKM), Bangi 43600, Malaysia"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-1832-6266","authenticated-orcid":false,"given":"Mohd Ambri","family":"Mohamed","sequence":"additional","affiliation":[{"name":"Institute of Microengineering and Nanoelectronics (IMEN), National University of Malaysia (UKM), Bangi 43600, Malaysia"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2022,10,26]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"2513","DOI":"10.1021\/nl048435y","article-title":"Percolation in transparent and conducting carbon nanotube networks","volume":"4","author":"Hu","year":"2004","journal-title":"Nano Lett."},{"key":"ref_2","first-page":"83","article-title":"Electrical and Structural Characterization of Graphene Carbon Nanotubes Hybrids (GCH)","volume":"12","author":"Theng","year":"2019","journal-title":"Structures"},{"key":"ref_3","doi-asserted-by":"crossref","first-page":"4","DOI":"10.1143\/JJAP.49.02BD08","article-title":"Fabrication and characterization of carbon nanotube field-effect transistors using ferromagnetic electrodes with different coercivities","volume":"49","author":"Mohamed","year":"2010","journal-title":"Jpn. J. Appl. Phys."},{"key":"ref_4","doi-asserted-by":"crossref","first-page":"222","DOI":"10.1016\/j.trac.2015.12.002","article-title":"Carbon nanotubes and graphene nano field-effect transistor-based biosensors","volume":"79","author":"Tran","year":"2016","journal-title":"TrAC Trends Anal. Chem."},{"key":"ref_5","doi-asserted-by":"crossref","first-page":"1301","DOI":"10.17576\/jsm-2019-4806-19","article-title":"Recent progress on fabrication of zinc oxide nanorod-based field effect transistor biosensors","volume":"48","author":"Karim","year":"2019","journal-title":"Sains Malays."},{"key":"ref_6","doi-asserted-by":"crossref","first-page":"17881","DOI":"10.1038\/s41598-017-18169-1","article-title":"Peptide aptamer-modified single-walled carbon nanotube-based transistors for high-performance biosensors","volume":"7","author":"Tung","year":"2017","journal-title":"Sci. Rep."},{"key":"ref_7","doi-asserted-by":"crossref","first-page":"9679","DOI":"10.1007\/s10853-019-03554-0","article-title":"High sensitivity detection of human serum albumin using a novel magnetoelastic immunosensor","volume":"54","author":"Liu","year":"2019","journal-title":"J. Mater. Sci."},{"key":"ref_8","doi-asserted-by":"crossref","first-page":"322","DOI":"10.1007\/s00216-005-3400-4","article-title":"Carbon nanotube transistors for biosensing applications","volume":"384","author":"Gruner","year":"2006","journal-title":"Anal. Bioanal. Chem."},{"key":"ref_9","doi-asserted-by":"crossref","first-page":"960","DOI":"10.1016\/j.bios.2015.07.061","article-title":"Selective electrochemical sensing of human serum albumin by semi-covalent molecular imprinting","volume":"74","author":"Cieplak","year":"2015","journal-title":"Biosens. Bioelectron."},{"key":"ref_10","doi-asserted-by":"crossref","first-page":"32","DOI":"10.1007\/s12575-009-9008-x","article-title":"Size and shape of protein molecules at the nanometer level determined by sedimentation, gel filtration, and electron microscopy","volume":"11","author":"Erickson","year":"2009","journal-title":"Biol. Proced. Online"},{"key":"ref_11","unstructured":"Peters, T. (1995). Foreword. All about Albumin, Academic Press."},{"key":"ref_12","doi-asserted-by":"crossref","unstructured":"Smales, C.M., and James, D.C. (2005). Therapeutic Proteins, Humana Press.","DOI":"10.1385\/1592599222"},{"key":"ref_13","doi-asserted-by":"crossref","first-page":"4477","DOI":"10.3182\/20140824-6-ZA-1003.01333","article-title":"On translation of LD, IL and SFC given according to IEC-61131 for hardware synthesis of reconfigurable logic controller","volume":"19","author":"Milik","year":"2014","journal-title":"IFAC Proc. Vol."},{"key":"ref_14","doi-asserted-by":"crossref","first-page":"471","DOI":"10.1373\/clinchem.2013.210302","article-title":"State of the art for measurement of urine albumin: Comparison of routine measurement procedures to isotope dilution tandem mass spectrometry","volume":"60","author":"Bachmann","year":"2014","journal-title":"Clin. Chem."},{"key":"ref_15","doi-asserted-by":"crossref","first-page":"1513","DOI":"10.1007\/s00604-016-1815-6","article-title":"Determination of human serum albumin using a single-walled carbon nanotube-FET modified with bromocresol green","volume":"183","author":"Kim","year":"2016","journal-title":"Microchim. Acta"},{"key":"ref_16","doi-asserted-by":"crossref","first-page":"7883","DOI":"10.1021\/acs.nanolett.8b03690","article-title":"Direct measurement of \u03c0 coupling at the single molecule level using a carbon nanotube force sensor","volume":"18","author":"Hong","year":"2018","journal-title":"Nano Lett."},{"key":"ref_17","doi-asserted-by":"crossref","first-page":"5175","DOI":"10.1166\/jnn.2017.13796","article-title":"Ultrasensitive Detection of Oligonucleotides: Single-Walled Carbon Nanotube Transistor Assembled by DNA Block Copolymer","volume":"17","author":"Kim","year":"2017","journal-title":"J. Nanosci. Nanotechnol."},{"key":"ref_18","first-page":"58","article-title":"Electrochemical immunosensor for alpha-fetoprotein based on prussian blue-carbon nanotube@polydopamine","volume":"13","author":"Sun","year":"2017","journal-title":"Micro Nano Lett."},{"key":"ref_19","doi-asserted-by":"crossref","first-page":"367","DOI":"10.1016\/j.snb.2018.08.030","article-title":"Electrochemical functionalization of single-walled carbon nanotubes with amine-terminated dendrimers encapsulating Pt nanoparticles: Toward facile field-effect transistor-based sensing platforms","volume":"275","author":"Lee","year":"2018","journal-title":"Sens. Actuators B Chem."},{"key":"ref_20","doi-asserted-by":"crossref","first-page":"107982","DOI":"10.1016\/j.bioelechem.2021.107982","article-title":"Carbon nanotube field-effect transistor (CNT-FET)-based biosensor for rapid detection of SARS-CoV-2 (COVID-19) surface spike protein S1","volume":"143","author":"Zamzami","year":"2022","journal-title":"Bioelectrochemistry"},{"key":"ref_21","unstructured":"Ervin, M.H., and Miller, B.S. (2010). Air Brush Fabricated Carbon Nanotube Supercapacitor Electrodes, Defense Technical Information Center."},{"key":"ref_22","doi-asserted-by":"crossref","first-page":"10","DOI":"10.1016\/j.jtice.2020.12.008","article-title":"Immuno-probed graphene nanoplatelets on electrolyte-gated field-effect transistor for stable cortisol quantification in serum","volume":"117","author":"Ruslinda","year":"2020","journal-title":"J. Taiwan Inst. Chem. Eng."},{"key":"ref_23","doi-asserted-by":"crossref","first-page":"695","DOI":"10.1016\/j.bios.2015.10.008","article-title":"Silicon nanowire biosensors for detection of cardiac troponin I (cTnI) with high sensitivity","volume":"77","author":"Kim","year":"2016","journal-title":"Biosens. Bioelectron."},{"key":"ref_24","doi-asserted-by":"crossref","first-page":"77","DOI":"10.4028\/p-073fwj","article-title":"Methods for Estimating Composition of Single Walled Carbon Nanotubes Based on Electronic Type","volume":"1055","author":"Yahya","year":"2022","journal-title":"Mater. Sci. Forum"},{"key":"ref_25","doi-asserted-by":"crossref","first-page":"11084","DOI":"10.1039\/C4NR02133A","article-title":"Inkjet printing of flexible high-performance carbon nanotube transparent conductive films by \u201ccoffee ring effect\u201d","volume":"6","author":"Shimoni","year":"2014","journal-title":"Nanoscale"},{"key":"ref_26","doi-asserted-by":"crossref","unstructured":"Polikarpov, Y.A., Romashkin, A.V., Struchkov, N.S., and Levin, D.D. (2019, January 28\u201331). High uniform carbon nanotube thin films spray deposition on substrates with patterned structures having height difference. Proceedings of the 2019 IEEE Conference of Russian Young Researchers in Electrical and Electronic Engineering (EIConRus), Saint Petersburg, Russia.","DOI":"10.1109\/EIConRus.2019.8657225"},{"key":"ref_27","doi-asserted-by":"crossref","first-page":"72","DOI":"10.1016\/j.carbon.2013.04.069","article-title":"Fabrication of carbon nanotube thin films on flexible substrates by spray deposition and transfer printing","volume":"61","author":"Abdelhalim","year":"2013","journal-title":"Carbon N. Y."},{"key":"ref_28","doi-asserted-by":"crossref","first-page":"574","DOI":"10.1016\/j.carbon.2015.05.036","article-title":"Temperature dependent separation of metallic and semiconducting carbon nanotubes using gel agarose chromatography","volume":"93","author":"Yahya","year":"2015","journal-title":"Carbon N. Y."},{"key":"ref_29","doi-asserted-by":"crossref","unstructured":"Yahya, I., Mustaza, S.M., and Abdullah, H. (2018). Carbon Nanotube-Activated Thin Film Transparent Conductor Applications, Intech Open.","DOI":"10.5772\/intechopen.79367"},{"key":"ref_30","doi-asserted-by":"crossref","first-page":"1435","DOI":"10.1103\/PhysRevB.10.1435","article-title":"Percolation and conductivity: A computer study: II","volume":"10","author":"Seager","year":"1974","journal-title":"Phys. Rev. B"},{"key":"ref_31","first-page":"343","article-title":"Effect of CNT Agglomeration on the Electrical Conductivity and Percolation Threshold of Nanocomposites: A Micromechanics-based Approach","volume":"103","author":"Yang","year":"2014","journal-title":"Comput. Model. Eng. Sci."},{"key":"ref_32","doi-asserted-by":"crossref","first-page":"677","DOI":"10.1021\/nl052406l","article-title":"Design criteria for transparent single-wall carbon nanotube thin-film transistors","volume":"6","author":"Unalan","year":"2006","journal-title":"Nano Lett."},{"key":"ref_33","doi-asserted-by":"crossref","first-page":"129406","DOI":"10.1016\/j.snb.2020.129406","article-title":"Understanding and improving carbon nanotube-electrode contact in bottom-contacted nanotube gas sensors","volume":"331","author":"Jung","year":"2021","journal-title":"Sens. Actuators B Chem."},{"key":"ref_34","first-page":"30","article-title":"On Contact Resistance of Carbon Nanotubes","volume":"1","author":"An","year":"2013","journal-title":"Int. J. Theor. Appl. Nanotechnol."},{"key":"ref_35","doi-asserted-by":"crossref","first-page":"178","DOI":"10.1002\/pssr.200701115","article-title":"Electrical properties of transparent carbon nanotube networks prepared through different techniques","volume":"1","author":"Lima","year":"2007","journal-title":"Phys. Status Solidi Rapid Res. Lett."},{"key":"ref_36","doi-asserted-by":"crossref","unstructured":"Slattery, A.D., Shearer, C.J., Shapter, J.G., Blanch, A.J., Quinton, J.S., and Gibson, C.T. (2018). Improved application of carbon nanotube atomic force microscopy probes using peakforce tapping mode. Nanomaterials, 8.","DOI":"10.3390\/nano8100807"},{"key":"ref_37","doi-asserted-by":"crossref","first-page":"226802","DOI":"10.1103\/PhysRevLett.92.226802","article-title":"Multimode transport in schottky-barrier carbon-nanotube field-effect transistors","volume":"92","author":"Appenzeller","year":"2004","journal-title":"Phys. Rev. Lett."},{"key":"ref_38","doi-asserted-by":"crossref","unstructured":"Hecht, D., and Gr\u00fcner, G. (2009). Solution Cast Films of Carbon Nanotubes for Transparent Conductors and Thin Film Transistors. Flexible Electronics, Springer.","DOI":"10.1007\/978-0-387-74363-9_10"},{"key":"ref_39","first-page":"1","article-title":"Performance Analysis of Cntfet and Mosfet Focusing Channel Length, Carrier Mobility and Ballistic Conduction in High Speed Switching","volume":"3","author":"Kabir","year":"2014","journal-title":"Int. J. Adv. Mater. Sci. Eng."},{"key":"ref_40","doi-asserted-by":"crossref","first-page":"90","DOI":"10.1016\/j.microrel.2012.09.015","article-title":"Revisiting MOSFET threshold voltage extraction methods","volume":"53","author":"Muci","year":"2013","journal-title":"Microelectron. Reliab."},{"key":"ref_41","doi-asserted-by":"crossref","first-page":"332","DOI":"10.3390\/electronics2040332","article-title":"Variability and reliability of single-walled carbon nanotube field effect transistors","volume":"2","author":"Islam","year":"2013","journal-title":"Electronics"},{"key":"ref_42","doi-asserted-by":"crossref","first-page":"388","DOI":"10.1016\/j.apsusc.2015.01.107","article-title":"Progress of porous silicon APTES-functionalization by FTIR investigations","volume":"331","author":"Majoul","year":"2015","journal-title":"Appl. Surf. Sci."},{"key":"ref_43","doi-asserted-by":"crossref","first-page":"111401","DOI":"10.1016\/j.msec.2020.111401","article-title":"Photoluminescence label-free immunosensor for the detection of Aflatoxin B1 using polyacrylonitrile\/zinc oxide nanofibers","volume":"118","author":"Myndrul","year":"2021","journal-title":"Mater. Sci. Eng. C"},{"key":"ref_44","doi-asserted-by":"crossref","first-page":"15344","DOI":"10.1007\/s10853-021-06288-0","article-title":"Zinc oxide nanorods-based immuno-field-effect transistor for human serum albumin detection","volume":"56","author":"Siti","year":"2021","journal-title":"J. Mater. Sci."},{"key":"ref_45","doi-asserted-by":"crossref","unstructured":"Xu, W., Wei, Y., Xing, D., Chen, Q., and Luo, S. (2007, January 23\u201327). Quantification of human serum albumin by highly sensitive chemiluminescence method. Proceedings of the 2007 IEEE\/ICME International Conference on Complex Medical Engineering, Beijing, China.","DOI":"10.1109\/ICCME.2007.4382036"}],"container-title":["Sensors"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.mdpi.com\/1424-8220\/22\/21\/8212\/pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2025,10,11]],"date-time":"2025-10-11T01:03:30Z","timestamp":1760144610000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.mdpi.com\/1424-8220\/22\/21\/8212"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2022,10,26]]},"references-count":45,"journal-issue":{"issue":"21","published-online":{"date-parts":[[2022,11]]}},"alternative-id":["s22218212"],"URL":"https:\/\/doi.org\/10.3390\/s22218212","relation":{},"ISSN":["1424-8220"],"issn-type":[{"value":"1424-8220","type":"electronic"}],"subject":[],"published":{"date-parts":[[2022,10,26]]}}}