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Zhao Z, Zharnikov M. Gold Nanoparticle-Loaded Porous Poly(ethylene glycol) Nanosheets for Electrochemical Detection of H 2O 2. NANOMATERIALS (BASEL, SWITZERLAND) 2023; 13:3137. [PMID: 38133034 PMCID: PMC10745603 DOI: 10.3390/nano13243137] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/17/2023] [Revised: 12/06/2023] [Accepted: 12/12/2023] [Indexed: 12/23/2023]
Abstract
The effective detection of hydrogen peroxide (H2O2) in different environments and, above all, in biological media, is an important practical issue. To this end, we designed a novel electrochemical sensor for H2O2 detection by introducing gold nanoparticles (AuNPs) into the porous poly(ethylene glycol) (PEG) matrix formed by the thermally activated crosslinking of amino- and epoxy-decorated STAR-PEG precursors. The respective composite PEG-AuNP films could be readily prepared on oxidized Si substrates, separated from them as free-standing nanosheets, and transferred as H2O2 sensing elements onto the working electrode of the electrochemical cell, with the performance of the sensing element relied on the established catalytic activity of AuNPs with respect to H2O2 decomposition. The sensitivity, detection limit, and the operation range of the composite PEG-AuNP sensors were estimated at ~3.4 × 102 μA mM-1 cm-2, 0.17 μM of H2O2, and 20 μM-3.5 mM of H2O2, respectively, which are well comparable with the best values for other types of H2O2 sensors reported recently in literature. The particular advantages of the composite PEG-AuNP sensors are commercial source materials, a simple fabrication procedure, the bioinert character of the PEG matrix, the 3D character of the AuNP assembly, and the possibility of transferring the nanosheet sensing element to any secondary substrate, including the glassy carbon electrode of the electrochemical cell. In particular, the bioinert character of the PEG matrix can be of importance for potential biological and biomedical applications of the designed sensing platform.
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Affiliation(s)
| | - Michael Zharnikov
- Angewandte Physikalische Chemie, Universität Heidelberg, Im Neuenheimer Feld 253, 69120 Heidelberg, Germany;
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2
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Zhao Z, Zharnikov M. Exploiting epoxy-rich poly(ethylene glycol) films for highly selective ssDNA sensing via electrochemical impedance spectroscopy. Phys Chem Chem Phys 2023; 25:26538-26548. [PMID: 37752830 DOI: 10.1039/d3cp03851c] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 09/28/2023]
Abstract
This study introduces an alternative approach to immobilize thiolated single-stranded DNA (ssDNA) for the DNA sensing. In contrast to the standard, monomolecular assembly of such moieties on gold substrate, over the thiolate-gold anchors, we propose to use bioinert, porous polyethylene glycol (PEG) films as a 3D template for ssDNA immobilization. The latter process relies on the reaction between the thiol group of the respectively decorated ssDNA and the epoxy groups in the epoxy-rich PEG matrix. The immobilization process and subsequent hybridization ability of the resulting sensing assembly were monitored using cyclic voltammetry and electrochemical impedance spectroscopy, with the latter tool proving itself as the most suitable transduction technique. Electrochemical data confirmed the successful immobilization of thiol-decorated ssDNA probes into the PEG matrix over the thiol-epoxy linkage as well as high hybridization efficiency, selectivity, and sensitivity of the resulting DNA sensor. Whereas this sensor was equivalent to the direct ssDNA assembly in terms of the efficiency, it exhibited a better selectivity and bioinert properties in view of the bioinert character of the PEG matrix. The above findings place PEG films as a promising platform for highly selective ssDNA sensing, leveraging their flexible chemistry, 3D character, and bioinert properties.
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Affiliation(s)
- Zhiyong Zhao
- Angewandte Physikalische Chemie, Universität Heidelberg, Im Neuenheimer Feld 253, 69120 Heidelberg, Germany.
| | - Michael Zharnikov
- Angewandte Physikalische Chemie, Universität Heidelberg, Im Neuenheimer Feld 253, 69120 Heidelberg, Germany.
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3
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Balser S, Zhao Z, Zharnikov M, Terfort A. Effect of the crosslinking agent on the biorepulsive and mechanical properties of polyglycerol membranes. Colloids Surf B Biointerfaces 2023; 225:113271. [PMID: 36996629 DOI: 10.1016/j.colsurfb.2023.113271] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2023] [Revised: 02/28/2023] [Accepted: 03/16/2023] [Indexed: 04/01/2023]
Abstract
Polyglycerol (PG) based surfaces materials and surfaces are well-established bio-compatible materials. Crosslinking of the dendrimeric molecules via their OH groups improves their mechanical stability up to the point that free-standing materials can be attained. Here, we investigate the effect of different crosslinkers on PG films regarding their biorepulsivity and mechanical properties. For this purpose, PG films with different thicknesses (15, 50 and 100 nm) were prepared by polymerizing glycidol in a ring-opening polymerization onto hydroxyl-terminated Si substrates. These films were then crosslinked using ethylene glycol diglycidyl ether (EGDGE), divinyl sulfone (DVS), glutaraldehyde (GA), 1,11-di(mesyloxy)-3,6,9-trioxaundecane (TEG-Ms2) or 1,11-dibromo-3,6,9-trioxaundecane (TEG-Br2), respectively. While DVS, TEG-Ms2, and TEG-Br2 resulted in slightly thinned films, presumably due to loss of unbound material, increase of film thickness was observed with GA and, in particular, EDGDE, what can be explained by the different crosslinking mechanisms. The biorepulsive properties of the crosslinked PG films were characterized by water contact angle (WCA) goniometry and various adsorption assays involving proteins (serum albumine, fibrinogen, γ-globulin) and bacteria (E. coli), showing that some crosslinkers (EGDGE, DVS) improved the biorepulsive properties, while others deteriorated them (TEG-Ms2, TEG-Br2, GA). As the crosslinking stabilized the films, it was possible to use a lift-off procedure to obtain free-standing membranes if the thickness of the films was 50 nm or larger. Their mechanical properties were examined with a bulge test showing high elasticities, with the Young's moduli increasing in the order GA ≈ EDGDE < TEG-Br2 ≈ TEG-Ms2 < DVS.
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Affiliation(s)
- Sebastian Balser
- Goethe University Frankfurt, Department of Chemistry, Institute of Inorganic and Analytical Chemistry, Max-von-Laue-Str. 7, 60438 Frankfurt, Germany
| | - Zhiyong Zhao
- Heidelberg University, Department of Applied Physical Chemistry, Im Neuenheimer Feld 253, 69120 Heidelberg, Germany
| | - Michael Zharnikov
- Heidelberg University, Department of Applied Physical Chemistry, Im Neuenheimer Feld 253, 69120 Heidelberg, Germany.
| | - Andreas Terfort
- Goethe University Frankfurt, Department of Chemistry, Institute of Inorganic and Analytical Chemistry, Max-von-Laue-Str. 7, 60438 Frankfurt, Germany.
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Zhao Z, Das S, Zharnikov M. Rational Design of Porous Poly(ethylene glycol) Films as a Matrix for ssDNA Immobilization and Hybridization. Bioengineering (Basel) 2022; 9:bioengineering9090414. [PMID: 36134960 PMCID: PMC9496007 DOI: 10.3390/bioengineering9090414] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2022] [Revised: 08/22/2022] [Accepted: 08/23/2022] [Indexed: 11/24/2022] Open
Abstract
Poly(ethylene glycol) (PEG) films, fabricated by thermally induced crosslinking of amine- and epoxy-terminated four-arm STAR-PEG precursors, were used as porous and bioinert matrix for single-stranded DNA (ssDNA) immobilization and hybridization. The immobilization relied on the reaction between the amine groups in the films and N-hydroxy succinimide (NHS) ester groups of the NHS-ester-decorated ssDNA. Whereas the amount of reactive amine groups in the films with the standard 1:1 composition of the precursors turned out to be too low for efficient immobilization, it could be increased noticeably using an excess (2:1) concentration of the amine-terminated precursor. The respective films retained the bioinertness of the 1:1 prototype and could be successfully decorated with probe ssDNA, resulting in porous, 3D PEG-ssDNA sensing assemblies. These assemblies exhibited high selectivity with respect to the target ssDNA strands, with a hybridization efficiency of 78–89% for the matching sequences and full inertness for non-complementary strands. The respective strategy can be applied to the fabrication of DNA microarrays and DNA sensors. As a suitable transduction technique, requiring no ssDNA labeling and showing high sensitivity in the PEG-ssDNA case, electrochemical impedance spectroscopy is suggested.
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Elastic Properties of Poly(ethylene glycol) Nanomembranes and Respective Implications. MEMBRANES 2022; 12:membranes12050509. [PMID: 35629834 PMCID: PMC9143594 DOI: 10.3390/membranes12050509] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/13/2022] [Revised: 05/03/2022] [Accepted: 05/05/2022] [Indexed: 12/04/2022]
Abstract
Free-standing poly(ethylene glycol) (PEG) membranes were prepared from amine- and epoxy-terminated four-arm STAR-PEG precursors in a thickness range of 40–320 nm. The membranes feature high stability and an extreme elasticity, as emphasized by the very low values of Young’s modulus, varying from 2.08 MPa to 2.6 MPa over the studied thickness range. The extreme elasticity of the membranes stems from the elastomer-like character of the PEG network, consisting of the STAR-PEG cores interconnected by crosslinked PEG chains. This elasticity is only slightly affected by a moderate reduction in the interconnections at a deviation from the standard 1:1 composition of the precursors. However, both the elasticity and stability of the membranes are strongly deteriorated by a strong distortion of the network imposed by electron irradiation of the membranes. In contrast, exposure of the membranes to ultraviolet (UV) light (254 nm) does not affect their elastic properties, supporting the assumption that the only effect of such treatment is the decomposition of the PEG material with subsequent desorption of the released fragments. An analysis of the data allowed for the exclusion of so called “hot electrons” as a possible mechanism behind the modification of the PEG membranes by UV light.
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Funahashi Y, Yoshinaka Y, Takada K, Kaneko T. Self-Standing Nanomembranes of Super-Tough Plastics. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2022; 38:5128-5134. [PMID: 34918512 DOI: 10.1021/acs.langmuir.1c02193] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/14/2023]
Abstract
Nanomembranes are effective coating materials for protecting substrates from external stimuli; however, they are generally not self-standing owing to their low mechanical toughness. Self-standing nanomembranes would be an innovative development in the field of nanotechnology including miniaturized devices. In this study, self-standing nanomembranes were developed by spin-casting supertough polyamides over dimethylformamide solution. The polyamides were synthesized by the polycondensation of two derivatives of 4,4'-diamino-α-truxillic acid (4ATA) with slightly bent diphenylcyclobutane in the core. Mechanical evaluation of the 4ATA polyamides having an appropriate composition of aliphatic diacids revealed a high strain-energy density of 231 MJ m-3 at its maximum, which is significantly tougher than spider silk. The nanocoats with a thickness of several hundred nanometers showing interference fringes were able to be peeled off the glass substrate without breaking, owing to its ultrahigh toughness. The self-standing nanomembrane would be applied to flexible devices in the future.
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Affiliation(s)
- Yasuyoshi Funahashi
- Graduate School of Advanced Science and Technology, Japan Advanced Institute of Science and Technology, 1-1 Asahidai, Nomi, Ishikawa 923 1292, Japan
| | - Yohei Yoshinaka
- Graduate School of Advanced Science and Technology, Japan Advanced Institute of Science and Technology, 1-1 Asahidai, Nomi, Ishikawa 923 1292, Japan
- The George and Josephine Butler Laboratory for Polymer Research, Department of Chemistry, University of Florida, Gainesville, Florida 32611-7200, United States
| | - Kenji Takada
- Graduate School of Advanced Science and Technology, Japan Advanced Institute of Science and Technology, 1-1 Asahidai, Nomi, Ishikawa 923 1292, Japan
| | - Tatsuo Kaneko
- Graduate School of Advanced Science and Technology, Japan Advanced Institute of Science and Technology, 1-1 Asahidai, Nomi, Ishikawa 923 1292, Japan
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Hafner D, Jordan R. Substrate-independent Cu(0)-mediated controlled radical polymerization: grafting of block copolymer brushes from poly(dopamine) modified surfaces. Polym Chem 2020. [DOI: 10.1039/c9py01343a] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
A method is presented combining poly(dopamine) chemistry and surface-initiated Cu(0)-mediated controlled radical polymerization (SI-CuCRP). Polymer brushes and block copolymer brushes are grafted independent of the original surface properties.
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Affiliation(s)
- Daniel Hafner
- Professur für Makromolekulare Chemie
- Technische Universität Dresden
- 01062 Dresden
- Germany
| | - Rainer Jordan
- Professur für Makromolekulare Chemie
- Technische Universität Dresden
- 01062 Dresden
- Germany
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Scherr J, Neuhaus A, Parey K, Klusch N, Murphy BJ, Zickermann V, Kühlbrandt W, Terfort A, Rhinow D. Noncovalent Functionalization of Carbon Substrates with Hydrogels Improves Structural Analysis of Vitrified Proteins by Electron Cryo-Microscopy. ACS NANO 2019; 13:7185-7190. [PMID: 31117383 DOI: 10.1021/acsnano.9b02651] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
In electron cryo-microscopy, structure determination of protein molecules is frequently hampered by adsorption of the particles to the support film material, typically amorphous carbon. Here, we report that pyrene derivatives with one or two polyglycerol (PG) side chains bind to the amorphous carbon films, forming a biorepulsive hydrogel layer so that the number of protein particles in the vitreous ice drastically increases. This approach could be extended by adding a hydrogel-functionalized carbon nanotube network (HyCaNet, the hydrogel again being formed from the PG-pyrene derivatives), which stabilized the protein-containing thin ice films during imaging with the electron beam. The stabilization resulted in reduced particle motion by up to 70%. These substrates were instrumental for determining the structure of a large membrane protein complex.
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Affiliation(s)
- Julian Scherr
- Department of Chemistry, Institute of Inorganic and Analytical Chemistry , Goethe-University Frankfurt , Max-von-Laue-Str. 7 , 60438 Frankfurt , Germany
| | - Alexander Neuhaus
- Department of Structural Biology , Max Planck Institute of Biophysics , Max-von-Laue-Str. 3 , 60438 Frankfurt , Germany
| | - Kristian Parey
- Department of Structural Biology , Max Planck Institute of Biophysics , Max-von-Laue-Str. 3 , 60438 Frankfurt , Germany
| | - Niklas Klusch
- Department of Structural Biology , Max Planck Institute of Biophysics , Max-von-Laue-Str. 3 , 60438 Frankfurt , Germany
| | - Bonnie J Murphy
- Department of Structural Biology , Max Planck Institute of Biophysics , Max-von-Laue-Str. 3 , 60438 Frankfurt , Germany
| | - Volker Zickermann
- Structural Bioenergetics Group , Institute of Biochemistry II, Medical School , Max-von-Laue-Str. 9 , 60438 Frankfurt , Germany
| | - Werner Kühlbrandt
- Department of Structural Biology , Max Planck Institute of Biophysics , Max-von-Laue-Str. 3 , 60438 Frankfurt , Germany
| | - Andreas Terfort
- Department of Chemistry, Institute of Inorganic and Analytical Chemistry , Goethe-University Frankfurt , Max-von-Laue-Str. 7 , 60438 Frankfurt , Germany
| | - Daniel Rhinow
- Department of Structural Biology , Max Planck Institute of Biophysics , Max-von-Laue-Str. 3 , 60438 Frankfurt , Germany
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9
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Polymer electrolytes based on a homogeneous poly(ethylene glycol) network and their application to polymer actuators. Electrochim Acta 2019. [DOI: 10.1016/j.electacta.2018.12.142] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register]
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10
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Khan M, Schuster S, Zharnikov M. Chemical derivatization and biofunctionalization of hydrogel nanomembranes for potential biomedical and biosensor applications. Phys Chem Chem Phys 2016; 18:12035-42. [DOI: 10.1039/c5cp07840g] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
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11
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Cramer AD, Gambinossi F, Wischerhoff E, Laschewsky A, Miller R, Ferri JK. Flexible thermoresponsive nanomembranes at the aqueous–air interface. Chem Commun (Camb) 2015; 51:877-80. [DOI: 10.1039/c4cc07359b] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Thermoresponsive freestanding nanomembranes were grown by surface-initiated polymerization at the aqueous–air interface of a pendant drop. We demonstrate formation of liquid-like interfaces supporting anisotropic stress and mechanical flexibility.
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Affiliation(s)
- Ashley D. Cramer
- Lafayette College
- Department of Chemical and Biomolecular Engineering
- Easton
- USA
| | - Filippo Gambinossi
- Lafayette College
- Department of Chemical and Biomolecular Engineering
- Easton
- USA
| | - Erik Wischerhoff
- Fraunhofer Institute for Applied Polymer Research
- D-14476 Potsdam-Golm
- Germany
| | - André Laschewsky
- Fraunhofer Institute for Applied Polymer Research
- D-14476 Potsdam-Golm
- Germany
- University of Potsdam
- Institute of Chemistry
| | - Reinhard Miller
- Max Planck Institute of Colloids and Interfaces
- D-14424 Potsdam/Golm
- Germany
| | - James K. Ferri
- Lafayette College
- Department of Chemical and Biomolecular Engineering
- Easton
- USA
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12
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Yu X, Xiong Z, Li J, Wu Z, Wang Y, Liu F. Surface PEGylation on PLA membranes via micro-swelling and crosslinking for improved biocompatibility/hemocompatibility. RSC Adv 2015. [DOI: 10.1039/c5ra23394a] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
A feasible and efficient strategy was developed to enable persistent PEGylation on a PLA membrane surface via micro-swelling and subsequent UV-initiated crosslinking of poly(ethylene glycol) diacrylate.
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Affiliation(s)
- Xuemin Yu
- Ningbo Institute of Materials Technology & Engineering
- Chinese Academy of Sciences
- Ningbo
- P. R. China
| | - Zhu Xiong
- Ningbo Institute of Materials Technology & Engineering
- Chinese Academy of Sciences
- Ningbo
- P. R. China
| | - Jinglong Li
- Ningbo Institute of Materials Technology & Engineering
- Chinese Academy of Sciences
- Ningbo
- P. R. China
| | - Ziyang Wu
- Ningbo Institute of Materials Technology & Engineering
- Chinese Academy of Sciences
- Ningbo
- P. R. China
| | - Yunze Wang
- Ningbo Institute of Materials Technology & Engineering
- Chinese Academy of Sciences
- Ningbo
- P. R. China
| | - Fu Liu
- Ningbo Institute of Materials Technology & Engineering
- Chinese Academy of Sciences
- Ningbo
- P. R. China
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Pérez-Madrigal MM, Armelin E, Puiggalí J, Alemán C. Insulating and semiconducting polymeric free-standing nanomembranes with biomedical applications. J Mater Chem B 2015; 3:5904-5932. [DOI: 10.1039/c5tb00624d] [Citation(s) in RCA: 39] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Free-standing nanomembranes, which are emerging as versatile elements in biomedical applications, are evolving from being composed of insulating (bio)polymers to electroactive conducting polymers.
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Affiliation(s)
- Maria M. Pérez-Madrigal
- Departament d'Enginyeria Química
- ETSEIB
- Universitat Politècnica de Catalunya
- Barcelona E-08028
- Spain
| | - Elaine Armelin
- Departament d'Enginyeria Química
- ETSEIB
- Universitat Politècnica de Catalunya
- Barcelona E-08028
- Spain
| | - Jordi Puiggalí
- Departament d'Enginyeria Química
- ETSEIB
- Universitat Politècnica de Catalunya
- Barcelona E-08028
- Spain
| | - Carlos Alemán
- Departament d'Enginyeria Química
- ETSEIB
- Universitat Politècnica de Catalunya
- Barcelona E-08028
- Spain
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Meyerbröker N, Zharnikov M. Hydrogel nanomembranes as templates for patterned deposition of nanoparticles on arbitrary substrates. ACS APPLIED MATERIALS & INTERFACES 2014; 6:14729-14735. [PMID: 25019522 DOI: 10.1021/am504358a] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
Patterns of nanoparticles (NPs) on solid supports are usually restricted to a particular substrate or a class of substrates. Here we present a procedure that decouples the patterning step from the target substrate, enabling the fabrication of custom designed NP assemblies on nearly any solid support, including nonflat ones. The procedure relies on a hydrogel template prepared on the primary, conductive substrate and transferred to the target support as a sacrificial nanomembrane. The template is structured by electron beam lithography (EBL) which seals predefined areas of poly(ethylene glycol) based hydrogel film, making them inert to NP deposition in contrast to pristine areas that adsorb NPs in high densities. The deposition of NPs, occurring from an aqueous solution into the transferred membrane, follows EBL generated structure, delivering the desired NP pattern on the target support after removal of the organic matrix. Efficiency and flexibility of the procedure is illustrated by creating a variety of representative submicrometer patterns of densely packed gold and silver NPs on glass, including a useful pattern of a miniaturized quick-response code. The arrangement of NPs in these patterns corresponds to the negative image of EBL generated template. This significantly reduces the exposure time for designs where large areas covered with NPs are separated by thin, NP-free stripes.
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Affiliation(s)
- Nikolaus Meyerbröker
- Applied Physical Chemistry, Heidelberg University , Im Neuenheimer Feld 253, 69120 Heidelberg, Germany
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