Javad Garousi

Development of a radiolabeled β-human chorionic gonadotropin

Development of a radiolabeled β-human chorionic gonadotropin β-Human chorionic gonadotropin (β-hCG) was successively labeled with [67Ga]-gallium chloride after conjugation with freshly prepared diethylenetriaminepentaacetic acid dianhydride (ccDTPA). After solid phase purification of the radiolabeled hormone, high performance liquid chromatography showed radiochemical purity higher than 95 % under optimized conditions (specific activity = 22-23 TBq mM-1, labeling efficiency 80 %). Preliminary in vivo studies (ID g-1, %) in male wild-type rats showed marked gonadal uptake of the tracer after 240 minutes in agreement with the biodistribution studies and reported β-hCG receptors. Target to blood ratios were 5.1 and 15.2 after 3 and 24 hours, respectively, while target to muscle ratios were 35 and 40 after 3 and 24 hours, respectively. Razvoj radiomarkiranog β-humanog koriogonadotropina β-humani korionski gonadotropin (β-hCG) uspješno je markiran s [67Ga] galijevim kloridom nakon konjugacije sa svježe priređenim dianhidridom dietilentriaminpentaoctene kiseline (ccDTPA). Nakon čišćenja radiomarkiranog hormona na čvrstoj fazi, radiokemijska čistoća bila je prema HPLC veća od 95 % (specifična aktivnost = 22-23 TBq mM-1, učinkovitost markiranja 80 %). Preliminarni in vivo pokusi (ID g-1, %) na mužjacima divljeg tipa štakora pokazali su da obilježeni hormon značajno ulazi u gonade nakon 240 minuta, što je u suglasnosti s ispitivanjima biodistribucije i podacima o receptorima za β-hCG. Omjer koncentracija u gonadama i krvi bio je 5,1, odnosno 15,2 nakon 3, odnosno 24 sata, dok je omjer koncentracija u gonadama i mišićima bio 35, odnosno 40 nakon 3, odnosno 24 sata.