Selective Nonenzymatic Amperometric Detection of Lactic Acid in Human Sweat Utilizing a Multi-Walled Carbon Nanotube (MWCNT)-Polypyrrole Core-Shell Nanowire

Lactic acid plays an important role as a biochemical indicator for sports medicine and clinical diagnosis. The detection of lactic acid in sweat is a promising technique without any intrusive inconvenience or risk of infection. In this study, we present a selective nonenzymatic amperometric detection method for lactic acid in human sweat utilizing a multi-wall carbon nanotube (MWCNT)-polypyrrole core-shell nanowire. Because polypyrrole is a p-type conducting polymer, onto which anions are exclusively doped, leading to charge transfer, it offers selective detection for lactate anions at a specific potential, while being inert to the neutral and cationic species contained in human sweat. A chronoamperometric study reveals good sensing performance for lactic acid with a high sensitivity of 2.9 μA mM−1 cm−2 and detection limit of 51 μM. Furthermore, the MWCNT-polypyrrole nanowire exhibits excellent selectivity for lactic acid over interfering species, such as sodium chloride, glucose, urea, and riboflavin, which coexist with lactic acid in sweat. Finally, a nonenzymatic amperometric sensor for the selective detection of lactic acid in human sweat is demonstrated on commercial flexible electrodes. The results demonstrate the potential applications of the MWCNT-polypyrrole core-shell nanowire as a nonenzymatic amperometric lactate sensor.

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Preparation of CNTs/PANi Core/Shell-Structured Nanowires and Improvement of Sensitivity of Chemical Sensors

Materials Science Forum ◽

10.4028/www.scientific.net/msf.686.438 ◽

2011 ◽

Vol 686 ◽

pp. 438-447

Author(s):

Xing Fa Ma ◽

Shu Juan Niu ◽

Ming Jun Gao ◽

Xiao Chun He ◽

Guang Li

Keyword(s):

Carbon Nanotube ◽

Chemical Sensors ◽

Gas Sensing ◽

In Situ Polymerization ◽

Core Shell ◽

Gas Sensitivity ◽

Flexible Polymer ◽

Transmission Electron ◽

Potential Applications ◽

The Fourier Transform

In order to improve the sensing-properties of carbon nanotube based composite for potential applications in chemical sensors, CNTs/PANi core/shell-structured nanowires were prepared with in-situ polymerization approach. A series of characterizations was carried out by TEM (transmission electron microscopy), the Fourier-Transform Infrared (FTIR) spectra, and so on. A chemical prototype sensor was constructed based on CNTs/PANi core/shell-structured nanowires and interdigital-structured electrodes on flexible polymer substrate. The gas-sensing behaviors of the sensor to some gases operating at room temperature were examined. Results showed that the sensitivity of CNTs/PANi core/shell-structured nanowires was increased dramaticly compared with pure carbon nanotube materials. This provides a carbon nanotube based composite materials with enhanced gas-sensitivity, which would have potential applications in some chemical sensors.

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Core-shell structure of carbon nanotube nanocapsules reinforced poly(lactic acid) composites

Journal of Applied Polymer Science ◽

10.1002/app.44919 ◽

2017 ◽

Vol 134 (23) ◽

Cited By ~ 4

Author(s):

Gaihong Wu ◽

Shuqiang Liu ◽

Xiongying Wu ◽

Xuemei Ding

Keyword(s):

Lactic Acid ◽

Carbon Nanotube ◽

Shell Structure ◽

Poly Lactic Acid ◽

Core Shell ◽

Core Shell Structure

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A Label and Probe-Free Zika Virus Immunosensor Prussian Blue@carbon Nanotube-Based for Amperometric Detection of the NS2B Protein

Biosensors ◽

10.3390/bios11050157 ◽

2021 ◽

Vol 11 (5) ◽

pp. 157

Author(s):

Bárbara V. M. Silva ◽

Marli T. Cordeiro ◽

Marco A. B. Rodrigues ◽

Ernesto T. A. Marques ◽

Rosa F. Dutra

Keyword(s):

Carbon Nanotube ◽

Prussian Blue ◽

Zika Virus ◽

Point Of Care ◽

Amperometric Detection ◽

Cross Reactivity ◽

Structural Protein ◽

Serum Samples ◽

Polypyrrole Composite ◽

Congenital Disabilities

Zika virus (ZIKV) is a mosquito-borne infection, predominant in tropical and subtropical regions causing international concern due to the ZIKV disease having been associated with congenital disabilities, especially microcephaly and other congenital abnormalities in the fetus and newborns. Development of strategies that minimize the devastating impact by monitoring and preventing ZIKV transmission through sexual intercourse, especially in pregnant women, since no vaccine is yet available for the prevention or treatment, is critically important. ZIKV infection is generally asymptomatic and cross-reactivity with dengue virus (DENV) is a global concern. An innovative screen-printed electrode (SPE) was developed for amperometric detection of the non-structural protein (NS2B) of ZIKV by exploring the intrinsic redox catalytic activity of Prussian blue (PB), incorporated into a carbon nanotube–polypyrrole composite. Thus, this immunosensor has the advantage of electrochemical detection without adding any redox-probe solution (probe-less detection), allowing a point-of-care diagnosis. It was responsive to serum samples of only ZIKV positive patients and non-responsive to negative ZIKV patients, even if the sample was DENV positive, indicating a possible differential diagnosis between them by NS2B. All samples used here were confirmed by CDC protocols, and immunosensor responses were also checked in the supernatant of C6/36 and in Vero cell cultures infected with ZIKV.

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Designing an Interlayer-Widened MoS2-Packed Nitrogen-Rich Carbon Nanotube Core–Shell Structure for Redox-Mediated Quasi-Solid-State Supercapacitors

ACS Applied Energy Materials ◽

10.1021/acsaem.0c02739 ◽

2021 ◽

Vol 4 (3) ◽

pp. 2218-2230

Author(s):

Sudhakaran Moopri Singer Pandiyarajan ◽

Ganesh Kumar Veerasubramani ◽

Roshan Mangal Bhattarai ◽

Gnanaselvan Gnanasekaran ◽

Sang Jae Kim ◽

...

Keyword(s):

Carbon Nanotube ◽

Solid State ◽

Shell Structure ◽

Core Shell ◽

Core Shell Structure

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Flow injection analysis with amperometric detection of polyphenols at carbon nanotube/polyvinylpyrrolidone-modified electrodes as classification tool for white wine varieties

Microchemical Journal ◽

10.1016/j.microc.2020.105836 ◽

2021 ◽

Vol 162 ◽

pp. 105836

Author(s):

Mónica Moreno ◽

Alberto Sánchez Arribas ◽

Laura González ◽

Esperanza Bermejo ◽

Antonio Zapardiel ◽

...

Keyword(s):

Carbon Nanotube ◽

Flow Injection ◽

Flow Injection Analysis ◽

Amperometric Detection ◽

Modified Electrodes ◽

White Wine ◽

Classification Tool

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Bonding Wood Veneer with Biobased Poly(Lactic Acid) Thermoplastic Polyesters: Potential Applications for Consolidated Wood Veneer and Overlay Products

Fibers ◽

10.3390/fib8080050 ◽

2020 ◽

Vol 8 (8) ◽

pp. 50

Author(s):

Warren J. Grigsby ◽

Arpit Puri ◽

Marc Gaugler ◽

Jan Lüedtke ◽

Andreas Krause

Keyword(s):

Tensile Strength ◽

Lactic Acid ◽

Cold Water ◽

Performance Criteria ◽

Poly Lactic Acid ◽

Wood Veneer ◽

Pressing Temperature ◽

Strength Performance ◽

Potential Applications ◽

Laminated Panels

This study reports on the use of poly(lactic acid) (PLA) as a renewable thermoplastic adhesive for laminated panels using birch, spruce, and pine veneers. Consolidated panels were prepared from veneer and PLA foils by hot-pressing from 140 to 180 °C to achieve minimum bondline temperatures. Evaluation of panel properties revealed that the PLA-bonded panels met minimum tensile strength and internal bond strength performance criteria. However, the adhesion interface which developed within individual bondlines varied with distinctions between hardwood and softwood species and PLA grades. Birch samples developed greater bondline strength with a higher pressing temperature using semi-crystalline PLA, whereas higher temperatures produced a poorer performance with the use of amorphous PLA. Panels formed with spruce or pine veneers had lower bondline performance and were also similarly distinguished by their pressing temperature and PLA grade. Furthermore, the potential for PLA-bonded laminated panels was demonstrated by cold water soak testing. Samples exhibiting relatively greater bondline adhesion had wet tensile strength values comparable to those tested in dry state. Our study outcomes suggest the potential for PLA bonding of veneers and panel overlays with the added benefits of being renewable and a no added formaldehyde system.

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Oligomer-Coated Carbon Nanotube Chemiresistive Sensors for Selective Detection of Nitroaromatic Explosives

ACS Applied Materials & Interfaces ◽

10.1021/acsami.5b01532 ◽

2015 ◽

Vol 7 (14) ◽

pp. 7471-7475 ◽

Cited By ~ 34

Author(s):

Yaqiong Zhang ◽

Miao Xu ◽

Benjamin R. Bunes ◽

Na Wu ◽

Dustin E. Gross ◽

...

Keyword(s):

Carbon Nanotube ◽

Selective Detection ◽

Nitroaromatic Explosives ◽

Coated Carbon

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One-Step Synthesis of Single-Wall Carbon Nanotube-ZnS Core-Shell Nanocables

Materials ◽

10.3390/ma9090718 ◽

2016 ◽

Vol 9 (9) ◽

pp. 718 ◽

Cited By ~ 3

Author(s):

Yanli Zhang ◽

Xiangming He ◽

Li Wang ◽

Jian Gao ◽

Jianjun Li

Keyword(s):

Carbon Nanotube ◽

Core Shell ◽

Single Wall Carbon Nanotube ◽

Single Wall Carbon ◽

One Step

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Core-shell Cu@C@ZIF-8 composite: a high-performance electrode material for electrochemical sensing of nitrite with high selectivity and sensitivity

Nanotechnology ◽

10.1088/1361-6528/ac3da7 ◽

2021 ◽

Author(s):

Feng Gao ◽

Xiaolong Tu ◽

Yongfang Yu ◽

Yansha Gao ◽

Jin Zou ◽

...

Keyword(s):

High Performance ◽

High Selectivity ◽

Limit Of Detection ◽

Metal Organic Framework ◽

High Sensitivity ◽

Electrochemical Sensing ◽

Core Shell ◽

Zeolitic Imidazolate Framework ◽

Sensing Platform ◽

The Difference

Abstract Herein, an efficient electrochemical sensing platform is proposed for selective and sensitive detection of nitrite on the basis of Cu@C@Zeolitic imidazolate framework-8 (Cu@C@ZIF-8) heterostructure. Core-shell Cu@C@ZIF-8 composite was synthesized by pyrolysis of Cu-metal-organic framework@ZIF-8 (Cu-MOF@ZIF-8) in Ar atmosphere on account of the difference of thermal stability between Cu-MOF and ZIF-8. For the sensing system of Cu@C@ZIF-8, ZIF-8 with proper pore size allows nitrite diffuse through the shell, while big molecules cannot, which ensures high selectivity of the sensor. On the other hand, Cu@C as electrocatalyst promotes the oxidation of nitrite, thereby resulting high sensitivity of the sensor. Accordingly, the Cu@C@ZIF-8 based sensor presents excellent performance for nitrite detection, which achieves a wide linear response range of 0.1 µM to 300.0 µM, and a low limit of detection (LOD) of 0.033 µM. In addition, the Cu@C@ZIF-8 sensor possesses excellent stability and reproducibility, and was employed to quantify nitrite in sausage samples with recoveries of 95.45-104.80%.

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