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Novel peptide sequence ("IQ-tag") with high affinity for NIR fluorochromes allows protein and cell specific labeling for in vivo imaging.

ABSTRACT: Probes that allow site-specific protein labeling have become critical tools for visualizing biological processes.Here we used phage display to identify a novel peptide sequence with nanomolar affinity for near infrared (NIR) (benz)indolium fluorochromes. The developed peptide sequence ("IQ-tag") allows detection of NIR dyes in a wide range of assays including ELISA, flow cytometry, high throughput screens, microscopy, and optical in vivo imaging.The described method is expected to have broad utility in numerous applications, namely site-specific protein imaging, target identification, cell tracking, and drug development.

SUBMITTER: Kelly KA

PROVIDER: S-EPMC1919420 | biostudies-literature | 2007 Jul

REPOSITORIES: biostudies-literature

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Novel peptide sequence ("IQ-tag") with high affinity for NIR fluorochromes allows protein and cell specific labeling for in vivo imaging.

Kelly Kimberly A KA Carson Jonathan J McCarthy Jason R JR Weissleder Ralph R

PloS one 20070725 7

<h4>Background</h4>Probes that allow site-specific protein labeling have become critical tools for visualizing biological processes.<h4>Methods</h4>Here we used phage display to identify a novel peptide sequence with nanomolar affinity for near infrared (NIR) (benz)indolium fluorochromes. The developed peptide sequence ("IQ-tag") allows detection of NIR dyes in a wide range of assays including ELISA, flow cytometry, high throughput screens, microscopy, and optical in vivo imaging.<h4>Significanc ...[more]

PMID: 17653285

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