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Affibody-functionalized gold-silica nanoparticles for Raman molecular imaging of the epidermal growth factor receptor.

ABSTRACT: The affibody functionalization of fluorescent surface-enhanced Raman scattering gold-silica nanoparticles as multimodal contrast agents for molecular imaging specific to epidermal growth factor receptor (EGFR) is reported. This nanoparticle bioconjugate reports EGFR-positive A431 tumors with a signal nearly 35-fold higher than EGFR-negative MDA-435S tumors. The low-level EGFR expression in adjacent healthy tissue is 7-fold lower than in the positive tumors. Validation via competitive inhibition reduces the signal by a factor of six, and independent measurement of EGFR via flow cytometry correlates at R(2) = 0.92.

SUBMITTER: Jokerst JV

PROVIDER: S-EPMC3386295 | biostudies-literature | 2011 Mar

REPOSITORIES: biostudies-literature

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Affibody-functionalized gold-silica nanoparticles for Raman molecular imaging of the epidermal growth factor receptor.

Jokerst Jesse V JV Miao Zheng Z Zavaleta Cristina C Cheng Zhen Z Gambhir Sanjiv S SS

Small (Weinheim an der Bergstrasse, Germany) 20110208 5

The affibody functionalization of fluorescent surface-enhanced Raman scattering gold-silica nanoparticles as multimodal contrast agents for molecular imaging specific to epidermal growth factor receptor (EGFR) is reported. This nanoparticle bioconjugate reports EGFR-positive A431 tumors with a signal nearly 35-fold higher than EGFR-negative MDA-435S tumors. The low-level EGFR expression in adjacent healthy tissue is 7-fold lower than in the positive tumors. Validation via competitive inhibition ...[more]

PMID: 21302357

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