title: Preparation of a Superhydrophobic and Peroxidase-like Activity Array Chip for H2O2 Sensing by Surface-Enhanced Raman Scattering.
abstract: In this paper, we propose a novel and simple method for preparing a dual-biomimetic functional array possessing both superhydrophobic and peroxidase-like activity that can be used for hydrogen peroxide (H2O2) sensing. The proposed method is an integration innovation that combines the above two properties and surface-enhanced Raman scattering (SERS). We integrated a series of well-ordered arrays of Au points (d = 1 mm) onto a superhydrophobic copper (Cu)/silver (Ag) surface by replicating an arrayed molybdenum template. Instead of using photoresists and the traditional lithography method, we utilized a chemical etching method (a substitution reaction between Cu and HAuCl4) with a Cu/Ag superhydrophobic surface as the barrier layer, which has the benefit of water repellency. The as-prepared Au points were observed to possess peroxidase-like activity, allowing for catalytic oxidation of the chromogenic molecule o-phenylenediamine dihydrochloride (OPD). Oxidation was evidenced by a color change in the presence of H2O2, which allows the array chip to act as an H2O2 sensor. In this study, the water repellency of the superhydrophobic surface was used to fabricate the array chip and increase the local reactant concentration during the catalytic reaction. As a result, the catalytic reaction occurred when only 2 μL of an aqueous sample (OPD/H2O2) was placed onto the Au point, and the enzymatic product, 2,3-diaminophenazine, showed a SERS signal distinguishable from that of OPD after mixing with 2 μL of colloidal Au. Using the dual-biomimetic functional array chip, quantitative analysis of H2O2 was performed by observing the change in the SERS spectra, which showed a concentration-dependent behavior for H2O2. This method allows for the detection of H2O2 at concentrations as low as 3 pmol per 2 μL of sample, which is a considerable advantage in H2O2 analysis. The as-prepared substrate was convenient for H2O2 detection because only a small amount of sample was required in each analysis. Highly sensitive detection was realized using SERS. Therefore, this chip was shown to exhibit significant potential for applications in bioanalysis.
authors.affiliation: Key Laboratory for Bionic Engineering of Ministry of Education, Jilin University , Changchun 130025, China.|Department of Chemistry, Institute for Molecular Science and Fusion Technology, Kangwon National University , Chunchon 200-701, Korea.
authors.forename: Zhi
authors.initials: Z
authors.lastname: Yu
authors.affiliation: Department of Chemistry, Institute for Molecular Science and Fusion Technology, Kangwon National University , Chunchon 200-701, Korea.
authors.forename: Yeonju
authors.initials: Y
authors.lastname: Park
authors.affiliation: Key Laboratory of Preparation and Applications of Environmental Friendly Materials, Ministry of Education, Jilin Normal University , Siping 136000, P. R. China.
authors.forename: Lei
authors.initials: L
authors.lastname: Chen
authors.affiliation: State Key Laboratory of Supramolecular Structure and Materials, Jilin University , Changchun 130012, P. R. China.
authors.forename: Bing
authors.initials: B
authors.lastname: Zhao
authors.affiliation: Department of Chemistry, Institute for Molecular Science and Fusion Technology, Kangwon National University , Chunchon 200-701, Korea.
authors.forename: Young Mee
authors.initials: YM
authors.lastname: Jung
authors.affiliation: Key Laboratory for Bionic Engineering of Ministry of Education, Jilin University , Changchun 130025, China.
authors.forename: Qian
authors.initials: Q
authors.lastname: Cong
mesh_terms: D015374:Biosensing Techniques; D003300:Copper / Q000737:chemistry; D006046:Gold / Q000737:chemistry; D006861:Hydrogen Peroxide / Q000302:isolation & purification*; D057927:Hydrophobic and Hydrophilic Interactions; D053768:Metal Nanoparticles / Q000737:chemistry*; D010544:Peroxidases / Q000737:chemistry; D010619:Phenazines / Q000737:chemistry; D010655:Phenylenediamines / Q000737:chemistry; D012834:Silver / Q000737:chemistry; D013059:Spectrum Analysis, Raman; D013499:Surface Properties; D014867:Water / Q000737:chemistry
chemical_list: D010619:Phenazines; D010655:Phenylenediamines; D014867:Water; C054312:2,3-diaminophenazine; D012834:Silver; D006046:Gold; D003300:Copper; C034193:1,2-diaminobenzene; D006861:Hydrogen Peroxide; D010544:Peroxidases
keywords: H2O2 quantitative analysis; dual-biomimetic functional; peroxidase-like activity; superhydrophobic; surface-enhanced Raman spectroscopy