Pt-Decorated MWCNTs-Ionic Liquid Composite-Based Hydrogen Peroxide Sensor to Study Microbial Metabolism Using Scanning Electrochemical Microscopy

Vrushali S. Joshi, Jens Kreth, Dipankar Koley

Research output: Contribution to journalArticle

10 Citations (Scopus)

Abstract

Hydrogen peroxide (H2O2) is a highly relevant metabolite in many biological processes, including the oral microbiome. To study this metabolite, we developed a 25 μm diameter, highly sensitive, nonenzymatic H2O2 sensor with a detection limit of 250 nM and a broad linear range of 250 nM to 7 mM. The sensor used the synergistic activity of the catalytically active Pt nanoparticles on a high surface area multiwalled carbon nanotube and conducting ionic liquid matrix to achieve high sensitivity (2.4 ± 0.24 mA cm-2 mM-1) for H2O2 oxidation. The unique composite allowed us to miniaturize the sensor and couple it with a Pt electrode (25 μm diameter each) for use as a dual scanning electrochemical microscopy probe. We could detect 65 ± 10 μM H2O2 produced by Streptococcus gordonii (Sg) in a simulated biofilm at 50 μm above its surface in the presence of 1 mM glucose and artificial saliva solution (pH 7.2 at 37 °C). Because of its high stability and low detection limit, the sensor showed a promising chemical image of H2O2 produced by Sg biofilms. We were also able to detect 30 μM H2O2 at 50 μm above the biofilm in the presence of the H2O2-decomposing salivary lactoperoxidase and thiocyanate, which would not otherwise be possible using an existing H2O2 assay. Thus, this sensor can potentially find applications in the study of other important biological processes in a complex matrix where circumstances demand a low detection limit in a compact space.

Original languageEnglish (US)
Pages (from-to)7709-7718
Number of pages10
JournalAnalytical Chemistry
Volume89
Issue number14
DOIs
StatePublished - Jul 18 2017

Fingerprint

Ionic Liquids
Metabolism
Hydrogen Peroxide
Microscopic examination
Scanning
Biofilms
Sensors
Composite materials
Metabolites
Artificial Saliva
Lactoperoxidase
Multiwalled carbon nanotubes (MWCN)
Assays
Nanoparticles
Glucose
Oxidation
Electrodes

ASJC Scopus subject areas

  • Analytical Chemistry

Cite this

Pt-Decorated MWCNTs-Ionic Liquid Composite-Based Hydrogen Peroxide Sensor to Study Microbial Metabolism Using Scanning Electrochemical Microscopy. / Joshi, Vrushali S.; Kreth, Jens; Koley, Dipankar.

In: Analytical Chemistry, Vol. 89, No. 14, 18.07.2017, p. 7709-7718.

Research output: Contribution to journalArticle

@article{06fb475762f04117a0766a042da9110c,
title = "Pt-Decorated MWCNTs-Ionic Liquid Composite-Based Hydrogen Peroxide Sensor to Study Microbial Metabolism Using Scanning Electrochemical Microscopy",
abstract = "Hydrogen peroxide (H2O2) is a highly relevant metabolite in many biological processes, including the oral microbiome. To study this metabolite, we developed a 25 μm diameter, highly sensitive, nonenzymatic H2O2 sensor with a detection limit of 250 nM and a broad linear range of 250 nM to 7 mM. The sensor used the synergistic activity of the catalytically active Pt nanoparticles on a high surface area multiwalled carbon nanotube and conducting ionic liquid matrix to achieve high sensitivity (2.4 ± 0.24 mA cm-2 mM-1) for H2O2 oxidation. The unique composite allowed us to miniaturize the sensor and couple it with a Pt electrode (25 μm diameter each) for use as a dual scanning electrochemical microscopy probe. We could detect 65 ± 10 μM H2O2 produced by Streptococcus gordonii (Sg) in a simulated biofilm at 50 μm above its surface in the presence of 1 mM glucose and artificial saliva solution (pH 7.2 at 37 °C). Because of its high stability and low detection limit, the sensor showed a promising chemical image of H2O2 produced by Sg biofilms. We were also able to detect 30 μM H2O2 at 50 μm above the biofilm in the presence of the H2O2-decomposing salivary lactoperoxidase and thiocyanate, which would not otherwise be possible using an existing H2O2 assay. Thus, this sensor can potentially find applications in the study of other important biological processes in a complex matrix where circumstances demand a low detection limit in a compact space.",
author = "Joshi, {Vrushali S.} and Jens Kreth and Dipankar Koley",
year = "2017",
month = "7",
day = "18",
doi = "10.1021/acs.analchem.7b01677",
language = "English (US)",
volume = "89",
pages = "7709--7718",
journal = "Analytical Chemistry",
issn = "0003-2700",
publisher = "American Chemical Society",
number = "14",

}

TY - JOUR

T1 - Pt-Decorated MWCNTs-Ionic Liquid Composite-Based Hydrogen Peroxide Sensor to Study Microbial Metabolism Using Scanning Electrochemical Microscopy

AU - Joshi, Vrushali S.

AU - Kreth, Jens

AU - Koley, Dipankar

PY - 2017/7/18

Y1 - 2017/7/18

N2 - Hydrogen peroxide (H2O2) is a highly relevant metabolite in many biological processes, including the oral microbiome. To study this metabolite, we developed a 25 μm diameter, highly sensitive, nonenzymatic H2O2 sensor with a detection limit of 250 nM and a broad linear range of 250 nM to 7 mM. The sensor used the synergistic activity of the catalytically active Pt nanoparticles on a high surface area multiwalled carbon nanotube and conducting ionic liquid matrix to achieve high sensitivity (2.4 ± 0.24 mA cm-2 mM-1) for H2O2 oxidation. The unique composite allowed us to miniaturize the sensor and couple it with a Pt electrode (25 μm diameter each) for use as a dual scanning electrochemical microscopy probe. We could detect 65 ± 10 μM H2O2 produced by Streptococcus gordonii (Sg) in a simulated biofilm at 50 μm above its surface in the presence of 1 mM glucose and artificial saliva solution (pH 7.2 at 37 °C). Because of its high stability and low detection limit, the sensor showed a promising chemical image of H2O2 produced by Sg biofilms. We were also able to detect 30 μM H2O2 at 50 μm above the biofilm in the presence of the H2O2-decomposing salivary lactoperoxidase and thiocyanate, which would not otherwise be possible using an existing H2O2 assay. Thus, this sensor can potentially find applications in the study of other important biological processes in a complex matrix where circumstances demand a low detection limit in a compact space.

AB - Hydrogen peroxide (H2O2) is a highly relevant metabolite in many biological processes, including the oral microbiome. To study this metabolite, we developed a 25 μm diameter, highly sensitive, nonenzymatic H2O2 sensor with a detection limit of 250 nM and a broad linear range of 250 nM to 7 mM. The sensor used the synergistic activity of the catalytically active Pt nanoparticles on a high surface area multiwalled carbon nanotube and conducting ionic liquid matrix to achieve high sensitivity (2.4 ± 0.24 mA cm-2 mM-1) for H2O2 oxidation. The unique composite allowed us to miniaturize the sensor and couple it with a Pt electrode (25 μm diameter each) for use as a dual scanning electrochemical microscopy probe. We could detect 65 ± 10 μM H2O2 produced by Streptococcus gordonii (Sg) in a simulated biofilm at 50 μm above its surface in the presence of 1 mM glucose and artificial saliva solution (pH 7.2 at 37 °C). Because of its high stability and low detection limit, the sensor showed a promising chemical image of H2O2 produced by Sg biofilms. We were also able to detect 30 μM H2O2 at 50 μm above the biofilm in the presence of the H2O2-decomposing salivary lactoperoxidase and thiocyanate, which would not otherwise be possible using an existing H2O2 assay. Thus, this sensor can potentially find applications in the study of other important biological processes in a complex matrix where circumstances demand a low detection limit in a compact space.

UR - http://www.scopus.com/inward/record.url?scp=85025123250&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=85025123250&partnerID=8YFLogxK

U2 - 10.1021/acs.analchem.7b01677

DO - 10.1021/acs.analchem.7b01677

M3 - Article

C2 - 28613833

AN - SCOPUS:85025123250

VL - 89

SP - 7709

EP - 7718

JO - Analytical Chemistry

JF - Analytical Chemistry

SN - 0003-2700

IS - 14

ER -