Highly Selective Protein Patterning on Gold-Silicon Substrates for Biosensor Applications

Veiseh, M; Zareie, HM; Zhang, M

Highly Selective Protein Patterning on Gold-Silicon Substrates for Biosensor Applications

Veiseh, M Zareie, HM Zhang, M

Permalink

Publisher:: American Chemical Society
Publication Type:: Journal Article
Citation:: Langmuir, 2002, 18 (17), pp. 6671 - 6678
Issue Date:: 2002-01

Closed Access

	Filename	Description	Size
	2006006463.pdf		731.98 kB	Adobe PDF	View/Open

Copyright Clearance Process

Recently Added
In Progress
Closed Access

This item is closed access and not available.

Full metadata record

Field	Value	Language
dc.contributor.author	Veiseh, M	en_US
dc.contributor.author	Zareie, HM	en_US
dc.contributor.author	Zhang, M	en_US
dc.date.issued	2002-01	en_US
dc.identifier.citation	Langmuir, 2002, 18 (17), pp. 6671 - 6678	en_US
dc.identifier.issn	0743-7463	en_US
dc.identifier.uri	http://hdl.handle.net/10453/578
dc.description.abstract	Proteins were precisely patterned on 2D sensor surfaces using photolithography and chemical selectivity. Microarrays of gold squares were fabricated on silicon substrates. The gold regions were modified with mixed COOH-terminated self-assembled monolayers (SAMs) to have a high affinity for the desired proteins or peptides. The silicon regions were modified with polyethylene glycol (PEG) by silanization to provide a high resistivity to protein adsorption. Protein surface coverage was visualized by fluorescence microscopy and atomic force microscopy (AFM). AFM was also used for studying protein morphology to understand the interaction of proteins with SAMs at the molecular level. Proteins and peptides immobilized on SAMs were examined by Fourier transform infrared (FTIR) spectroscopy. Contact angle measurements for surface wettability were conducted to confirm the success of the surface modification reactions. Protein resistance by the PEGs immobilized on bare silicon substrates and on the silicon regions of gold-patterned silicon substrates was compared, and it was found that the latter has a higher resistivity to protein adsorption. Both fluorescence and high-resolution AFM images indicated that bovine serum albumin (BSA) and fibronectin molecules formed a densely packed layer on the gold regions of the patterned substrates, while the immunoglobulin's (IgG) coverage was low. Specific antigen-antibody binding (BSA-anti-BSA) was studied using the surface plasmon resonance (SPR) technique for characterizing the bioactivity of the antigen attached to the gold substrates. The SPR results showed that the BSA proteins bound covalently to the gold surfaces have a much better bioactivity than those bound physically. This study suggests that protein or peptide, molecular structures, and the immobilization technique influence the coverage, morphology, and bioactivity of the attached proteins on the substrates which is crucial to the operational behavior of biosensors.	en_US
dc.publisher	American Chemical Society	en_US
dc.relation.ispartof	Langmuir	en_US
dc.relation.isbasedon	http://dx.doi.org/10.1021/la025529j	en_US
dc.subject.classification	Chemical Physics	en_US
dc.title	Highly Selective Protein Patterning on Gold-Silicon Substrates for Biosensor Applications	en_US
dc.type	Journal Article
utslib.citation.volume	17	en_US
utslib.citation.volume	18	en_US
utslib.for	0303 Macromolecular and Materials Chemistry	en_US
utslib.for	0306 Physical Chemistry (incl. Structural)	en_US
utslib.for	1007 Nanotechnology	en_US
pubs.embargo.period	Not known	en_US
pubs.organisational-group	/University of Technology Sydney
pubs.organisational-group	/University of Technology Sydney/Faculty of Science
pubs.organisational-group	/University of Technology Sydney/Faculty of Science/School of Mathematical and Physical Sciences
utslib.copyright.status	closed_access
pubs.consider-herdc	false	en_US
pubs.issue	17	en_US
pubs.volume	18	en_US

Abstract:

Proteins were precisely patterned on 2D sensor surfaces using photolithography and chemical selectivity. Microarrays of gold squares were fabricated on silicon substrates. The gold regions were modified with mixed COOH-terminated self-assembled monolayers (SAMs) to have a high affinity for the desired proteins or peptides. The silicon regions were modified with polyethylene glycol (PEG) by silanization to provide a high resistivity to protein adsorption. Protein surface coverage was visualized by fluorescence microscopy and atomic force microscopy (AFM). AFM was also used for studying protein morphology to understand the interaction of proteins with SAMs at the molecular level. Proteins and peptides immobilized on SAMs were examined by Fourier transform infrared (FTIR) spectroscopy. Contact angle measurements for surface wettability were conducted to confirm the success of the surface modification reactions. Protein resistance by the PEGs immobilized on bare silicon substrates and on the silicon regions of gold-patterned silicon substrates was compared, and it was found that the latter has a higher resistivity to protein adsorption. Both fluorescence and high-resolution AFM images indicated that bovine serum albumin (BSA) and fibronectin molecules formed a densely packed layer on the gold regions of the patterned substrates, while the immunoglobulin's (IgG) coverage was low. Specific antigen-antibody binding (BSA-anti-BSA) was studied using the surface plasmon resonance (SPR) technique for characterizing the bioactivity of the antigen attached to the gold substrates. The SPR results showed that the BSA proteins bound covalently to the gold surfaces have a much better bioactivity than those bound physically. This study suggests that protein or peptide, molecular structures, and the immobilization technique influence the coverage, morphology, and bioactivity of the attached proteins on the substrates which is crucial to the operational behavior of biosensors.

Please use this identifier to cite or link to this item:

http://hdl.handle.net/10453/578