title: Labelling of proteins with 11C in high specific radioactivity: [11C]albumin and [11C]transferrin.
abstract: A method for the 11C-labelling of proteins for use in positron emission tomography is presented. Human iron-free transferrin and human serum albumin were treated with [11C]cyanogen bromide of high specific radioactivity under physiological conditions to give the labelled proteins in high radiochemical yields using a simple and rapid procedure. In a typical experiment, 2.0 GBq of [11C]albumin was obtained in 28-32 min synthesis time counted from the end of bombardment. The radiochemical purity was in all cases > 98% and the specific radioactivity varied with the amount of protein between 10.7-141 GBq mumol-1 (0.3-3.8 Ci mumol-1). The radiochemical yield of labelled product as a function of pH and protein concentration was studied. The labelled products were characterized using both high performance liquid chromatography and high performance capillary electrophoresis with u.v.-and radiodetection in series.
authors.affiliation: Uppsala University PET Centre, Uppsala University Hospital, Sweden.
authors.forename: G
authors.initials: G
authors.lastname: Westerberg
authors.forename: B
authors.initials: B
authors.lastname: Långström
mesh_terms: D002245:Carbon Dioxide; D002250:Carbon Radioisotopes; D002851:Chromatography, High Pressure Liquid / Q000379:methods; D003488:Cyanogen Bromide; D006801:Humans; D007202:Indicators and Reagents; D007525:Isoelectric Focusing; D007553:Isotope Labeling / Q000379:methods*; D012709:Serum Albumin / Q000302:isolation & purification; D014168:Transferrin / Q000302:isolation & purification
chemical_list: D002250:Carbon Radioisotopes; D007202:Indicators and Reagents; D012709:Serum Albumin; D014168:Transferrin; D002245:Carbon Dioxide; D003488:Cyanogen Bromide