title: Efficient method for site-specific 18F-labeling of biomolecules using the rapid condensation reaction between 2-cyanobenzothiazole and cysteine.
abstract: An efficient method based on a rapid condensation reaction between 2-cyanobenzothiazole (CBT) and cysteine has been developed for (18)F-labeling of N-terminal cysteine-bearing peptides and proteins. An (18)F-labeled dimeric cRGD ([(18)F]CBTRGD(2)) has been synthesized with an excellent radiochemical yield (92% based on radio-HPLC conversion, 80% decay-corrected, and isolated yield) and radiochemical purity (>99%) under mild conditions using (18)F-CBT, and shown good in vivo tumor targeting efficiency for PET imaging. The labeling strategy was also applied to the site-specific (18)F-labeling of a protein, Renilla lucifierase (RLuc8) with a cysteine residue at its N-terminus. The protein labeling was achieved with 12% of decay-corrected radiochemical yield and more than 99% radiochemical purity. This strategy should provide a general approach for efficient and site-specific (18)F-labeling of various peptides and proteins for in vivo molecular imaging applications.
authors: Molecular Imaging Program at Stanford, Department of Radiology, Stanford University, 1201 Welch Road, Stanford, California 94305-5484, USA.
authors: Jongho
authors: J
authors: Jeon
authors: Bin
authors: B
authors: Shen
authors: Liqin
authors: L
authors: Xiong
authors: Zheng
authors: Z
authors: Miao
authors: Kyung Hyun
authors: KH
authors: Lee
authors: Jianghong
authors: J
authors: Rao
authors: Frederick T
authors: FT
authors: Chin
mesh_terms: D000818:Animals; D052160:Benzothiazoles / Q000737:chemistry*; D002851:Chromatography, High Pressure Liquid; D003545:Cysteine / Q000737:chemistry*; D019281:Dimerization; D005462:Fluorine Radioisotopes / Q000737:chemistry*; D051379:Mice; D008819:Mice, Nude; D009570:Nitriles / Q000737:chemistry*; D049268:Positron-Emission Tomography
chemical_list: C578355:2-cyanobenzothiazole; D052160:Benzothiazoles; D005462:Fluorine Radioisotopes; D009570:Nitriles; D003545:Cysteine