Dataset Information

Affinity-based Protein Surface Pattern Formation by Ligand Self-Selection from Mixed Protein Solutions.

ABSTRACT: Photolithographically prepared surface patterns of two affinity ligands (biotin and chloroalkane) specific for two proteins (streptavidin and HaloTag®, respectively) are used to spontaneously form high-fidelity surface patterns of the two proteins from their mixed solution. High affinity protein-surface self-selection onto patterned ligands on surfaces exhibiting low non-specific adsorption rapidly yields the patterned protein surfaces. Fluorescence images after protein immobilization show high specificity of the target proteins to their respective surface patterned ligands. Time-of-flight secondary ion mass spectrometry (ToF-SIMS) imaging further supports the chemical specificity of streptavidin and HaloTag® for their surface patterned ligands from mixed protein solutions. However, ToF-SIMS did detect some non-specific adsorption of bovine serum albumin, a masking protein present in excess in the adsorbing solutions, on the patterned surfaces. Protein amino acid composition, surface coverage, density and orientation are important parameters that determine the relative ToF-SIMS fragmentation pattern yields. ToF-SIMS amino acid-derived ion fragment yields summed to produce surface images can reliably determine which patterned surface regions contain bound proteins, but do not readily discriminate between different co-planar protein regions. Principal component analysis (PCA) of these ToF-SIMS data, however, improves discrimination of ions specific to each protein, facilitating surface pattern discrimination and contrast.

SUBMITTER: Grainger DW

PROVIDER: S-EPMC3597123 | biostudies-literature | 2009 Oct

REPOSITORIES: biostudies-literature

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Affinity-based Protein Surface Pattern Formation by Ligand Self-Selection from Mixed Protein Solutions.

Grainger David W DW Castner David G DG Dubey Manish M Emoto Kazunori K Takahashi Hironobu H

Advanced functional materials 20090810 19

Photolithographically prepared surface patterns of two affinity ligands (biotin and chloroalkane) specific for two proteins (streptavidin and HaloTag®, respectively) are used to spontaneously form high-fidelity surface patterns of the two proteins from their mixed solution. High affinity protein-surface self-selection onto patterned ligands on surfaces exhibiting low non-specific adsorption rapidly yields the patterned protein surfaces. Fluorescence images after protein immobilization show high ...[more]

PMID: 23504611

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Dataset Information

Affinity-based Protein Surface Pattern Formation by Ligand Self-Selection from Mixed Protein Solutions.

Publications

Affinity-based Protein Surface Pattern Formation by Ligand Self-Selection from Mixed Protein Solutions.

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