Direct fluorine-18 labeling of heat-sensitive biomolecules for positron emission tomography imaging using the Al18F-RESCA method.
Nat Protoc
; 13(10): 2330-2347, 2018 10.
Article
em En
| MEDLINE
| ID: mdl-30250289
ABSTRACT
Positron emission tomography (PET) is a quickly expanding, non-invasive molecular imaging technology, and there is high demand for new specific imaging probes. Herein, we present a generic protocol for direct radiolabeling of heat-sensitive biomolecules with the positron-emitting radioisotope fluorine-18 (18F) using the aluminum fluoride restrained complexing agent (Al18F-RESCA) method. The Al18F-RESCA method combines the chemical advantages of a chelator-based radiolabeling method with the unique physical properties of the radionuclide of choice, fluorine-18. Proteins of interest can be conjugated to RESCA via amine coupling using (±)-H3RESCA-TFP, followed by purification using size-exclusion chromatography (SEC). Next, RESCA-derivatized biomolecules can be labeled in one step, at room temperature (~20 °C) in an aqueous medium with aluminum fluoride (Al18F). Al18F-labeled proteins can be obtained with moderate (12-17 GBq/µmol) to good (80-85 GBq/µmol) apparent molar activity, depending on the starting activity of 18F-. In addition, satisfactory radiochemical yields (35-55%, non-decay corrected) and high radiochemical purity (>98%, using gel filtration or solid-phase purification) are obtained. The mild radiolabeling procedure takes 0.5 h to complete and can be used for direct labeling of vector molecules such as peptides, protein scaffolds, and engineered antibody fragments.
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Peptídeos
/
Radioisótopos de Flúor
/
Proteínas
/
Compostos de Alumínio
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Tomografia por Emissão de Pósitrons
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Complexos de Coordenação
/
Fluoretos
Tipo de estudo:
Diagnostic_studies
Limite:
Animals
Idioma:
En
Revista:
Nat Protoc
Ano de publicação:
2018
Tipo de documento:
Article
País de afiliação:
Bélgica