Dota noc

The peptidic precursors NOTA-[1-Nal³] octreotide acetate (NOTA-NOC) and DOTA-[1-Nal³] octreotide acetate (DOTA-NOC) were purchased from ABX (Radeberg, Germany). Aluminum chloride (AlCl₃·xH₂O, 99.999%), sodium acetate buffer for complexometry (pH 4.6), bovine serum albumin, sodium acetate (anhydrous, ≥99.999%), and acetic acid (≥99.0%, traceSELECT) were obtained from Sigma-Aldrich. Deionized (DI) water with a resistivity of 18.2 MQ·cm was acquired from a MilliQ Direct-Q 3 UV water purification system. AlCl₃·xH₂O (10 mM) in 0.5 M NaOAc, pH 4.1, was prepared from 408 mg anhydrous sodium acetate with 1.15 mL acetic acid to 50.0 mL DI water. To this solution, 120 mg AlCl₃·xH₂O (assumed to be fully hydrated, x = 6, Mw 242) was dissolved. Phosphate buffered saline and ethanol (100%) were acquired from the local hospital pharmacy. The fluoride-18 was produced by the standard proton bombardment of [¹⁸O]H₂O on a GE PETtrace cyclotron. The radiochemical yields and purities were determined by reverse phase HPLC (Phenomenex Jupiter C18, 150 × 4.6 mm, H₂O + 0.1% TFA:ACN gradient). The radioisotope conjugates were formulated in phosphate buffer containing 0.1% bovine serum albumin and applied for preclinical PET/CT imaging and biodistribution.