{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,6,3]],"date-time":"2026-06-03T16:12:00Z","timestamp":1780503120832,"version":"3.54.1"},"reference-count":50,"publisher":"MDPI AG","issue":"11","license":[{"start":{"date-parts":[[2019,6,4]],"date-time":"2019-06-04T00:00:00Z","timestamp":1559606400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100001809","name":"National Natural Science Foundation of China","doi-asserted-by":"publisher","award":["21804043"],"award-info":[{"award-number":["21804043"]}],"id":[{"id":"10.13039\/501100001809","id-type":"DOI","asserted-by":"publisher"}]},{"name":"Chenguang Program of Shanghai Education Development Foundation and Shanghai Municipal Education Commission","award":["15CGB03"],"award-info":[{"award-number":["15CGB03"]}]},{"DOI":"10.13039\/100012543","name":"Shanghai Science and Technology Development Foundation","doi-asserted-by":"publisher","award":["18YF1405800"],"award-info":[{"award-number":["18YF1405800"]}],"id":[{"id":"10.13039\/100012543","id-type":"DOI","asserted-by":"publisher"}]},{"name":"Chinese Post\u2212Doctoral Fund","award":["2018M632039"],"award-info":[{"award-number":["2018M632039"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>Potentiometric plasticizer-free solid-contact Pb2+-selective electrodes based on copolymer methyl methacrylate-n-butyl acrylate (MMA-BA) as membrane matrix and multi-walled carbon nanotubes (MWCNTs) as intermediate ion-to-electron transducing layer have been developed. The disposable electrodes were prepared by drop-casting the copolymer membrane onto a layer of MWCNTs, which deposited on golden disk electrodes. The obtained electrodes exhibited a sub-ppb level detection limit of 10\u221210 mol\u00b7L\u22121. The proposed electrodes demonstrated a Nernstian slope of 29.1 \u00b1 0.5 mV\/decade in the linear range from 2.0 \u00d7 10\u221210 to 1.5 \u00d7 10\u22123 mol\u00b7L\u22121. No interference from gases (O2 and CO2) or water films was observed. The electrochemical impedance spectroscopy of the fabricated electrodes was compared to that of plasticizer-free Pb2+-selective electrodes without MWCNTs as intermediated layers. The plasticizer-free MWCNTs-based Pb2+-selective electrodes can provide a promising platform for Pb(II) detection in environmental and clinical application.<\/jats:p>","DOI":"10.3390\/s19112550","type":"journal-article","created":{"date-parts":[[2019,6,5]],"date-time":"2019-06-05T09:37:58Z","timestamp":1559727478000},"page":"2550","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":11,"title":["Disposable Multi-Walled Carbon Nanotubes-Based Plasticizer-Free Solid-Contact Pb2+-Selective Electrodes with a Sub-PPB Detection Limit \u2020"],"prefix":"10.3390","volume":"19","author":[{"given":"Yueling","family":"Liu","sequence":"first","affiliation":[{"name":"Department of Food Quality and Safety, College of Management, Shanghai Sanda University, Shanghai 201209, China"},{"name":"State Key Laboratory of Bioreactor Engineering, Biomedical Nanotechnology Center, School of Biotechnology, East China University of Science and Technology, Shanghai 200237, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Yingying","family":"Gao","sequence":"additional","affiliation":[{"name":"State Key Laboratory of Bioreactor Engineering, Biomedical Nanotechnology Center, School of Biotechnology, East China University of Science and Technology, Shanghai 200237, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Rui","family":"Yan","sequence":"additional","affiliation":[{"name":"State Key Laboratory of Bioreactor Engineering, Biomedical Nanotechnology Center, School of Biotechnology, East China University of Science and Technology, Shanghai 200237, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Haobo","family":"Huang","sequence":"additional","affiliation":[{"name":"State Key Laboratory of Bioreactor Engineering, Biomedical Nanotechnology Center, School of Biotechnology, East China University of Science and Technology, Shanghai 200237, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Ping","family":"Wang","sequence":"additional","affiliation":[{"name":"State Key Laboratory of Bioreactor Engineering, Biomedical Nanotechnology Center, School of Biotechnology, East China University of Science and Technology, Shanghai 200237, China"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2019,6,4]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"56","DOI":"10.1016\/j.talanta.2016.06.050","article-title":"Solid contact potassium selective electrodes for biomedical applications\u2014A review","volume":"160","author":"Velde","year":"2016","journal-title":"Talanta"},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"199","DOI":"10.1016\/j.trac.2005.01.003","article-title":"Potentiometric sensors for trace-level analysis","volume":"24","author":"Bakker","year":"2005","journal-title":"Trends Anal. 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