No Cover Image

Journal article 163 views 27 downloads

Voltammetric Detection of Caffeine in Beverages at Nafion/Graphite Nanoplatelets Layer-by-Layer Films / Paolo, Bertoncello

Nanomaterials, Volume: 9, Issue: 2, Start page: 221

Swansea University Author: Paolo, Bertoncello

Check full text

DOI (Published version): 10.3390/nano9020221

Abstract

We report for the first time a procedure in which Nafion/Graphite nanoplatelets (GNPs) thin films are fabricated using a modified layer-by-layer (LbL) method. The method consists of dipping a substrate (quartz and/or glassy carbon electrodes) into a composite solution made of Nafion and GNPs dissolv...

Full description

Published in: Nanomaterials
ISSN: 2079-4991
Published: 2019
Online Access: Check full text

URI: https://cronfa.swan.ac.uk/Record/cronfa48773
Tags: Add Tag
No Tags, Be the first to tag this record!
first_indexed 2019-02-11T11:58:07Z
last_indexed 2019-03-26T12:22:10Z
id cronfa48773
recordtype SURis
fullrecord <?xml version="1.0"?><rfc1807><datestamp>2019-03-25T16:58:44.8088193</datestamp><bib-version>v2</bib-version><id>48773</id><entry>2019-02-08</entry><title>Voltammetric Detection of Caffeine in Beverages at Nafion/Graphite Nanoplatelets Layer-by-Layer Films</title><swanseaauthors><author><sid>ad352842aa5fe9c1947bd24ff61816c8</sid><ORCID>0000-0002-6557-7885</ORCID><firstname>Paolo</firstname><surname>Bertoncello</surname><name>Paolo Bertoncello</name><active>true</active><ethesisStudent>false</ethesisStudent></author></swanseaauthors><date>2019-02-08</date><deptcode>EEN</deptcode><abstract>We report for the first time a procedure in which Nafion/Graphite nanoplatelets (GNPs) thin films are fabricated using a modified layer-by-layer (LbL) method. The method consists of dipping a substrate (quartz and/or glassy carbon electrodes) into a composite solution made of Nafion and GNPs dissolved together in ethanol, followed by washing steps in water. This procedure allowed the fabrication of multilayer films of (Nafion/GNPs)n by means of hydrogen bonding and hydrophobic&#x2012;hydrophobic interactions between Nafion, GNPs, and the corresponding solid substrate. The average thickness of each layer evaluated using profilometer corresponds to ca. 50 nm. The as-prepared Nafion/GNPs LbL films were characterized using various spectroscopic techniques such as X-ray photoelectron spectroscopy (XPS), energy-dispersive X-ray spectroscopy (EDS), FTIR, and optical microscopy. This characterization highlights the presence of oxygen functionalities that support a mechanism of self-assembly via hydrogen bonding interactions, along with hydrophobic interactions between the carbon groups of GNPs and the Teflon-like (carbon&#x2012;fluorine backbone) of Nafion. We showed that Nafion/GNPs LbL films can be deposited onto glassy carbon electrodes and utilized for the voltammetric detection of caffeine in beverages. The results showed that Nafion/GNPs LbL films can achieve a limit of detection for caffeine (LoD) of 0.032 &#x3BC;M and linear range between 20&#x2012;250 &#x3BC;M using differential pulse voltammetry, whereas, using cyclic voltammetry LoD and linear range were found to be 24 &#x3BC;M and 50&#x2012;5000 &#x3BC;M, respectively. Voltammetric detection of caffeine in beverages showed good agreement between the values found experimentally and those reported by the beverage producers. The values found are also in agreement with those obtained using a standard spectrophotometric method. The proposed method is appealing because it allows the fabrication of Nafion/GNPs thin films in a simple fashion using a single-step procedure, rather than using composite solutions with opposite electrostatic charge, and also allows the detection of caffeine in beverages without any pre-treatment or dilution of the real samples. The proposed method is characterized by a fast response time without apparent interference, and the results were competitive with those obtained with other materials reported in the literature.</abstract><type>Journal Article</type><journal>Nanomaterials</journal><volume>9</volume><journalNumber>2</journalNumber><paginationStart>221</paginationStart><publisher/><issnElectronic>2079-4991</issnElectronic><keywords>Nafion; graphite nanoplatelets; caffeine; electrochemical sensors</keywords><publishedDay>31</publishedDay><publishedMonth>12</publishedMonth><publishedYear>2019</publishedYear><publishedDate>2019-12-31</publishedDate><doi>10.3390/nano9020221</doi><url/><notes/><college>COLLEGE NANME</college><department>Engineering</department><CollegeCode>COLLEGE CODE</CollegeCode><DepartmentCode>EEN</DepartmentCode><institution>Swansea University</institution><lastEdited>2019-03-25T16:58:44.8088193</lastEdited><Created>2019-02-08T10:18:06.7525138</Created><path><level id="1">College of Engineering</level><level id="2">Engineering</level></path><authors><author><firstname>Sandra</firstname><surname>Hernandez-Aldave</surname><order>1</order></author><author><firstname>Afshin</firstname><surname>Tarat</surname><order>2</order></author><author><firstname>James D.</firstname><surname>McGettrick</surname><order>3</order></author><author><firstname>Paolo</firstname><surname>Bertoncello</surname><orcid>0000-0002-6557-7885</orcid><order>4</order></author></authors><documents><document><filename>0048773-08022019102430.pdf</filename><originalFilename>hernandez-aldave2019.pdf</originalFilename><uploaded>2019-02-08T10:24:30.7170000</uploaded><type>Output</type><contentLength>15578967</contentLength><contentType>application/pdf</contentType><version>Version of Record</version><cronfaStatus>true</cronfaStatus><action/><embargoDate>2019-02-08T00:00:00.0000000</embargoDate><copyrightCorrect>true</copyrightCorrect><language>eng</language></document></documents></rfc1807>
spelling 2019-03-25T16:58:44.8088193 v2 48773 2019-02-08 Voltammetric Detection of Caffeine in Beverages at Nafion/Graphite Nanoplatelets Layer-by-Layer Films ad352842aa5fe9c1947bd24ff61816c8 0000-0002-6557-7885 Paolo Bertoncello Paolo Bertoncello true false 2019-02-08 EEN We report for the first time a procedure in which Nafion/Graphite nanoplatelets (GNPs) thin films are fabricated using a modified layer-by-layer (LbL) method. The method consists of dipping a substrate (quartz and/or glassy carbon electrodes) into a composite solution made of Nafion and GNPs dissolved together in ethanol, followed by washing steps in water. This procedure allowed the fabrication of multilayer films of (Nafion/GNPs)n by means of hydrogen bonding and hydrophobic‒hydrophobic interactions between Nafion, GNPs, and the corresponding solid substrate. The average thickness of each layer evaluated using profilometer corresponds to ca. 50 nm. The as-prepared Nafion/GNPs LbL films were characterized using various spectroscopic techniques such as X-ray photoelectron spectroscopy (XPS), energy-dispersive X-ray spectroscopy (EDS), FTIR, and optical microscopy. This characterization highlights the presence of oxygen functionalities that support a mechanism of self-assembly via hydrogen bonding interactions, along with hydrophobic interactions between the carbon groups of GNPs and the Teflon-like (carbon‒fluorine backbone) of Nafion. We showed that Nafion/GNPs LbL films can be deposited onto glassy carbon electrodes and utilized for the voltammetric detection of caffeine in beverages. The results showed that Nafion/GNPs LbL films can achieve a limit of detection for caffeine (LoD) of 0.032 μM and linear range between 20‒250 μM using differential pulse voltammetry, whereas, using cyclic voltammetry LoD and linear range were found to be 24 μM and 50‒5000 μM, respectively. Voltammetric detection of caffeine in beverages showed good agreement between the values found experimentally and those reported by the beverage producers. The values found are also in agreement with those obtained using a standard spectrophotometric method. The proposed method is appealing because it allows the fabrication of Nafion/GNPs thin films in a simple fashion using a single-step procedure, rather than using composite solutions with opposite electrostatic charge, and also allows the detection of caffeine in beverages without any pre-treatment or dilution of the real samples. The proposed method is characterized by a fast response time without apparent interference, and the results were competitive with those obtained with other materials reported in the literature. Journal Article Nanomaterials 9 2 221 2079-4991 Nafion; graphite nanoplatelets; caffeine; electrochemical sensors 31 12 2019 2019-12-31 10.3390/nano9020221 COLLEGE NANME Engineering COLLEGE CODE EEN Swansea University 2019-03-25T16:58:44.8088193 2019-02-08T10:18:06.7525138 College of Engineering Engineering Sandra Hernandez-Aldave 1 Afshin Tarat 2 James D. McGettrick 3 Paolo Bertoncello 0000-0002-6557-7885 4 0048773-08022019102430.pdf hernandez-aldave2019.pdf 2019-02-08T10:24:30.7170000 Output 15578967 application/pdf Version of Record true 2019-02-08T00:00:00.0000000 true eng
title Voltammetric Detection of Caffeine in Beverages at Nafion/Graphite Nanoplatelets Layer-by-Layer Films
spellingShingle Voltammetric Detection of Caffeine in Beverages at Nafion/Graphite Nanoplatelets Layer-by-Layer Films
Paolo, Bertoncello
title_short Voltammetric Detection of Caffeine in Beverages at Nafion/Graphite Nanoplatelets Layer-by-Layer Films
title_full Voltammetric Detection of Caffeine in Beverages at Nafion/Graphite Nanoplatelets Layer-by-Layer Films
title_fullStr Voltammetric Detection of Caffeine in Beverages at Nafion/Graphite Nanoplatelets Layer-by-Layer Films
title_full_unstemmed Voltammetric Detection of Caffeine in Beverages at Nafion/Graphite Nanoplatelets Layer-by-Layer Films
title_sort Voltammetric Detection of Caffeine in Beverages at Nafion/Graphite Nanoplatelets Layer-by-Layer Films
author_id_str_mv ad352842aa5fe9c1947bd24ff61816c8
author_id_fullname_str_mv ad352842aa5fe9c1947bd24ff61816c8_***_Paolo, Bertoncello
author Paolo, Bertoncello
format Journal article
container_title Nanomaterials
container_volume 9
container_issue 2
container_start_page 221
publishDate 2019
institution Swansea University
issn 2079-4991
doi_str_mv 10.3390/nano9020221
college_str College of Engineering
hierarchytype
hierarchy_top_id collegeofengineering
hierarchy_top_title College of Engineering
hierarchy_parent_id collegeofengineering
hierarchy_parent_title College of Engineering
department_str Engineering{{{_:::_}}}College of Engineering{{{_:::_}}}Engineering
document_store_str 1
active_str 0
description We report for the first time a procedure in which Nafion/Graphite nanoplatelets (GNPs) thin films are fabricated using a modified layer-by-layer (LbL) method. The method consists of dipping a substrate (quartz and/or glassy carbon electrodes) into a composite solution made of Nafion and GNPs dissolved together in ethanol, followed by washing steps in water. This procedure allowed the fabrication of multilayer films of (Nafion/GNPs)n by means of hydrogen bonding and hydrophobic‒hydrophobic interactions between Nafion, GNPs, and the corresponding solid substrate. The average thickness of each layer evaluated using profilometer corresponds to ca. 50 nm. The as-prepared Nafion/GNPs LbL films were characterized using various spectroscopic techniques such as X-ray photoelectron spectroscopy (XPS), energy-dispersive X-ray spectroscopy (EDS), FTIR, and optical microscopy. This characterization highlights the presence of oxygen functionalities that support a mechanism of self-assembly via hydrogen bonding interactions, along with hydrophobic interactions between the carbon groups of GNPs and the Teflon-like (carbon‒fluorine backbone) of Nafion. We showed that Nafion/GNPs LbL films can be deposited onto glassy carbon electrodes and utilized for the voltammetric detection of caffeine in beverages. The results showed that Nafion/GNPs LbL films can achieve a limit of detection for caffeine (LoD) of 0.032 μM and linear range between 20‒250 μM using differential pulse voltammetry, whereas, using cyclic voltammetry LoD and linear range were found to be 24 μM and 50‒5000 μM, respectively. Voltammetric detection of caffeine in beverages showed good agreement between the values found experimentally and those reported by the beverage producers. The values found are also in agreement with those obtained using a standard spectrophotometric method. The proposed method is appealing because it allows the fabrication of Nafion/GNPs thin films in a simple fashion using a single-step procedure, rather than using composite solutions with opposite electrostatic charge, and also allows the detection of caffeine in beverages without any pre-treatment or dilution of the real samples. The proposed method is characterized by a fast response time without apparent interference, and the results were competitive with those obtained with other materials reported in the literature.
published_date 2019-12-31T04:01:21Z
_version_ 1667901561214337024
score 10.900508