title: 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.
authors.affiliation: Molecular Imaging Program at Stanford, Department of Radiology, Stanford, CA 94305, USA.
authors.forename: Jesse V
authors.initials: JV
authors.lastname: Jokerst
authors.forename: Zheng
authors.initials: Z
authors.lastname: Miao
authors.forename: Cristina
authors.initials: C
authors.lastname: Zavaleta
authors.forename: Zhen
authors.initials: Z
authors.lastname: Cheng
authors.forename: Sanjiv S
authors.initials: SS
authors.lastname: Gambhir
mesh_terms: D045744:Cell Line, Tumor; D066246:ErbB Receptors / Q000032:analysis* / Q000378:metabolism; D006046:Gold / Q000737:chemistry*; D006801:Humans; D057054:Molecular Imaging; D053758:Nanoparticles / Q000737:chemistry*; D012822:Silicon Dioxide / Q000737:chemistry*; D013059:Spectrum Analysis, Raman
chemical_list: D006046:Gold; D012822:Silicon Dioxide; D066246:ErbB Receptors