Nanoceria-PAN Composite-Based Advanced Sorbent Material: A Major Step Forward in the Field of Clinical-Grade ~(68)Ge/~(68)Ga Generator

摘要

The ~(68)Ge/~(68)Ga generator has high potential for clinical positron emission tomography (PET) imaging. However, because of the unavailability of a suitable sorbent material, the commercially available ~(68)Ge/~(68)Ga generators are not directly adaptable for the preparation of ~(68)Ga-labeled radiopharmaceuticals. In view of this, a new nanoceria-polyacrylonitrile (PAN) composite sorbent has been synthesized by decomposition of a cerium oxalate precursor to cerium oxide and its subsequent incorporation in PAN matrix for the development of a clinical grade ~(68)Ge/~(68)Ga generator. The X-ray diffraction (XRD) studies and BET nitrogen adsorption technique revealed that nanocrystaiiine ceria had an average particle size of ~10 nm, surface area of 72 ± 3 m~2/g and an average pore size of 3.8 ± 0.1 A. Investigation of the distribution ratio (K_d) values for the prepared sorbent in 0.01 N HCl medium revealed the suitability of the sorbent for the quantitative retention of ~(68)Ge and efficient elution ofxlinical grade ~(68)Ga. A 370 MBq (10 mCi) ~(68)Ge/~(68)Ga chromatographic generator was developed using this sorbent,~(68)Ga could be regularly eluted from this generator with > 80 % elution yield. The eluted ~(68)Ga possess high radionuclidic purity (< 1 x 10~(-5) % of ~(68)Ge impurity), chemical purity (<0.1 ppm of Ce, Fe and Mn ions) and was amenable for the preparation of ~(68)Ga-labeled radiopharmaceuticals. The generator gave a consistent performance with respect to the elution yield and purity of ~(68)Ga over an extended period of 7 months.