title: Facile synthesis of carbon-11-labeled cholesterol-based cationic lipids as new potential PET probes for imaging of gene delivery in cancer.
abstract: Gene therapy based on gene delivery is a promising strategy for the treatment of various human diseases such as cancer. Cationic lipids represent one of the important synthetic gene delivery systems. There is a great interest in imaging of gene therapy using the biomedical imaging technique positron emission tomography (PET). Carbon-11-labeled cholesterol-based cationic lipids were first designed and synthesized as new potential PET probes for imaging of gene delivery in cancer. The [(11)C-methyl]quaternary amine target tracers, N-[(11)C]methyl-N-[4-(cholest-5-en-3beta-yloxycarbonyl)butyl]pyrrolidinium iodide ([(11)C]4a), N-[(11)C]methyl-N'-[4-(cholest-5-en-3beta-yloxycarbonyl)butyl]imidazolium iodide ([(11)C]4b), N-[(11)C]methyl-N-[4-(cholest-5-en-3beta-yloxycarbonyl)butyl]piperidinium iodide ([(11)C]4c), N-[(11)C]methyl-N-[4-(cholest-5-en-3beta-yloxycarbonyl)butyl]-4-methylpiperidinium iodide ([(11)C]4d), and N-[(11)C]methyl-N-[4-(cholest-5-en-3beta-yloxycarbonyl)butyl]morpholinium iodide ([(11)C]4e), were prepared from their corresponding tertiary amine precursors with [(11)C]methyl iodide ([(11)C]CH(3)I) through N-[(11)C]methylation and isolated by a simplified solid-phase extraction (SPE) method using a Silica Sep-Pak cartridge in 50-60% radiochemical yields decay corrected to end-of-bombardment (EOB), based on [(11)C]CO(2), and 111-185GBq/mumol specific activity at the end of synthesis (EOS).
authors.affiliation: Department of Radiology and Imaging Sciences, Indiana University School of Medicine, 1345 West 16(th) Street, L3-208, Indianapolis, IN 46202, USA.
authors.forename: Mingzhang
authors.initials: M
authors.lastname: Gao
authors.forename: Min
authors.initials: M
authors.lastname: Wang
authors.forename: Kathy D
authors.initials: KD
authors.lastname: Miller
authors.forename: George W
authors.initials: GW
authors.lastname: Sledge
authors.forename: Gary D
authors.initials: GD
authors.lastname: Hutchins
authors.forename: Qi-Huang
authors.initials: QH
authors.lastname: Zheng
mesh_terms: D002784:Cholesterol / Q000737:chemistry; D018014:Gene Transfer Techniques; D006801:Humans; D008055:Lipids / Q000138:chemical synthesis* / Q000737:chemistry*; D009682:Magnetic Resonance Spectroscopy; D015394:Molecular Structure; D009369:Neoplasms / Q000473:pathology*; D049268:Positron-Emission Tomography / Q000379:methods*; D011854:Radiochemistry
chemical_list: D008055:Lipids; D002784:Cholesterol