title: (111)In- and (203)Pb-Labeled Cyclic RGD Peptide Conjugate as an α(v)β(3) Integrin-Binding Radiotracer.
abstract: Methodology for site-specific modification and chelate conjugation of a cyclic RGD (cRGD) peptide for the preparation of a radiotracer molecular imaging agent suitable for detecting α(v)β(3) integrin is described. The method involves functionalizing the peptide with an aldehyde moiety and conjugation to a 1,4,7,10-tetraazacyclododecane-N,N',N″,N‴-tetraacetic acid (DOTA) derivative that possesses an aldehyde reactive aminooxy group. The binding assay of the (111)In-labeled peptide conjugate with α(v)β(3) integrin showed 60% bound when four equivalents of the integrin was added, a reasonable binding affinity for a mono-valent modified RGD peptide.
authors.affiliation: Radioimmune & Inorganic Chemistry Section, Radiation Oncology Branch, National Cancer Institute, 10 Center Drive, Bethesda, MD 20892.
authors.forename: Kido
authors.initials: K
authors.lastname: Nwe
authors.forename: Young-Seung
authors.initials: YS
authors.lastname: Kim
authors.forename: Diane E
authors.initials: DE
authors.lastname: Milenic
authors.forename: Kwamena E
authors.initials: KE
authors.lastname: Baidoo
authors.forename: Martin W
authors.initials: MW
authors.lastname: Brechbiel