Combination of Capped Gold Nanoslit Array and Electrochemistry for Sensitive Aqueous Mercuric Ions Detection

Label-free surface plasmon resonance (SPR) detection of mercuric ions in various aqueous solutions, using capped gold nanoslit arrays combined with electrochemical (EC) sensing technique, is demonstrated. The nanoslit arrays are fabricated on flexible cyclo-olefin polymer substrates by a nanoimprint...

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Main Authors: Cheng-Chuan Chen, Shu-Cheng Lo, Pei-Kuen Wei
Format: Article
Language:English
Published: MDPI AG 2021-12-01
Series:Nanomaterials
Subjects:
Online Access:https://www.mdpi.com/2079-4991/12/1/88
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author Cheng-Chuan Chen
Shu-Cheng Lo
Pei-Kuen Wei
author_facet Cheng-Chuan Chen
Shu-Cheng Lo
Pei-Kuen Wei
author_sort Cheng-Chuan Chen
collection DOAJ
description Label-free surface plasmon resonance (SPR) detection of mercuric ions in various aqueous solutions, using capped gold nanoslit arrays combined with electrochemical (EC) sensing technique, is demonstrated. The nanoslit arrays are fabricated on flexible cyclo-olefin polymer substrates by a nanoimprinting lithography method. The EC and SPR signals for the investigation of current responses and transmission SPR spectra are simultaneously measured during metal ions electrodeposition. Glycerol–water solution is studied to evaluate the resonant peak wavelength sensitivity (480.3 nm RIU<sup>−1</sup>) with a FOM of 40.0 RIU<sup>−1</sup> and the obtained intensity sensitivity is 1819.9%. The ferrocyanide/ferricyanide redox couple performs the diffusion controlled electrochemical processes (<i>R<sup>2</sup></i> = 0.99). By investigating the SPR intensity changes and wavelength shifts of various mercuric ion concentrations, the optical properties are evaluated under chronoamperometric conditions. The sensors are evaluated in the detection range between 100 μM and 10 nM with a detection limit of 1 μM. The time dependence of SPR signals and the selectivity of 10 μM Hg<sup>2+</sup> in the presence of 10 μM interfering metal ion species from Ca<sup>2+</sup>, Co<sup>2+</sup>, Ni<sup>2+</sup>, Na<sup>+</sup>, Cu<sup>2+</sup>, Pb<sup>2 +</sup> and Mn<sup>2+</sup> are determined. The capped gold nanoslit arrays show the selectivity of Hg<sup>2+</sup> and the EC sensing method is effectively utilized to aqueous Hg<sup>2+</sup> detection. This study provides a label-free detection technique of mercuric ions and this developed system is potentially applicable to detecting chemicals and biomolecules.
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spelling doaj.art-b51704a99a0b4dbb991b4bf793f9634b2023-11-23T12:01:19ZengMDPI AGNanomaterials2079-49912021-12-011218810.3390/nano12010088Combination of Capped Gold Nanoslit Array and Electrochemistry for Sensitive Aqueous Mercuric Ions DetectionCheng-Chuan Chen0Shu-Cheng Lo1Pei-Kuen Wei2Research Center for Applied Sciences, Academia Sinica, Taipei 11529, TaiwanResearch Center for Applied Sciences, Academia Sinica, Taipei 11529, TaiwanResearch Center for Applied Sciences, Academia Sinica, Taipei 11529, TaiwanLabel-free surface plasmon resonance (SPR) detection of mercuric ions in various aqueous solutions, using capped gold nanoslit arrays combined with electrochemical (EC) sensing technique, is demonstrated. The nanoslit arrays are fabricated on flexible cyclo-olefin polymer substrates by a nanoimprinting lithography method. The EC and SPR signals for the investigation of current responses and transmission SPR spectra are simultaneously measured during metal ions electrodeposition. Glycerol–water solution is studied to evaluate the resonant peak wavelength sensitivity (480.3 nm RIU<sup>−1</sup>) with a FOM of 40.0 RIU<sup>−1</sup> and the obtained intensity sensitivity is 1819.9%. The ferrocyanide/ferricyanide redox couple performs the diffusion controlled electrochemical processes (<i>R<sup>2</sup></i> = 0.99). By investigating the SPR intensity changes and wavelength shifts of various mercuric ion concentrations, the optical properties are evaluated under chronoamperometric conditions. The sensors are evaluated in the detection range between 100 μM and 10 nM with a detection limit of 1 μM. The time dependence of SPR signals and the selectivity of 10 μM Hg<sup>2+</sup> in the presence of 10 μM interfering metal ion species from Ca<sup>2+</sup>, Co<sup>2+</sup>, Ni<sup>2+</sup>, Na<sup>+</sup>, Cu<sup>2+</sup>, Pb<sup>2 +</sup> and Mn<sup>2+</sup> are determined. The capped gold nanoslit arrays show the selectivity of Hg<sup>2+</sup> and the EC sensing method is effectively utilized to aqueous Hg<sup>2+</sup> detection. This study provides a label-free detection technique of mercuric ions and this developed system is potentially applicable to detecting chemicals and biomolecules.https://www.mdpi.com/2079-4991/12/1/88gold nanoslitssurface plasmonelectrochemistrymercury ions
spellingShingle Cheng-Chuan Chen
Shu-Cheng Lo
Pei-Kuen Wei
Combination of Capped Gold Nanoslit Array and Electrochemistry for Sensitive Aqueous Mercuric Ions Detection
Nanomaterials
gold nanoslits
surface plasmon
electrochemistry
mercury ions
title Combination of Capped Gold Nanoslit Array and Electrochemistry for Sensitive Aqueous Mercuric Ions Detection
title_full Combination of Capped Gold Nanoslit Array and Electrochemistry for Sensitive Aqueous Mercuric Ions Detection
title_fullStr Combination of Capped Gold Nanoslit Array and Electrochemistry for Sensitive Aqueous Mercuric Ions Detection
title_full_unstemmed Combination of Capped Gold Nanoslit Array and Electrochemistry for Sensitive Aqueous Mercuric Ions Detection
title_short Combination of Capped Gold Nanoslit Array and Electrochemistry for Sensitive Aqueous Mercuric Ions Detection
title_sort combination of capped gold nanoslit array and electrochemistry for sensitive aqueous mercuric ions detection
topic gold nanoslits
surface plasmon
electrochemistry
mercury ions
url https://www.mdpi.com/2079-4991/12/1/88
work_keys_str_mv AT chengchuanchen combinationofcappedgoldnanoslitarrayandelectrochemistryforsensitiveaqueousmercuricionsdetection
AT shuchenglo combinationofcappedgoldnanoslitarrayandelectrochemistryforsensitiveaqueousmercuricionsdetection
AT peikuenwei combinationofcappedgoldnanoslitarrayandelectrochemistryforsensitiveaqueousmercuricionsdetection