ABSTRACT
Scandium-44g (half-life 3.97h [1]) shows promise for positron emission tomography (PET) imaging of longer biological processes than that of the current gold standard, 18F, due to its favorable decay parameters. One source of 44gSc is the long-lived parent nuclide 44Ti (half-life 60.0 a). A 44Ti/44gSc generator would have the ability to provide radionuclidically pure 44gSc on a daily basis. The production of 44Ti via the 45Sc(p,2n) reaction requires high proton beam currents and long irradiation times. Recovery and purification of no-carrier added (nca) 44Ti from scandium metal targets involves complex separation chemistry. In this study, separation systems based on solid phase extraction chromatography were investigated, including branched diglycolamide (BDGA) resin and hydroxamate based ZR resin. Results indicate that ZR resin in HCl media represents an effective 44Ti/44gSc separation system.
Subject(s)
Chromatography/methods , Protons , Radioisotopes/isolation & purification , Scandium/chemistry , Solid Phase Extraction/methods , Titanium/isolation & purification , Amides/chemistry , Hydrochloric Acid/chemistry , Kinetics , Resins, Synthetic/chemistry , SolutionsABSTRACT
An undescribed type of skin tumour, discovered in four cases, is reported. It is characterized by sweat-gland tumours (benign or malignant), with a common stromal haemangiomatous component which confers to it a peculiar pattern. Histogenetic possibilities are discussed. A collision mechanism between a pre-existent hamartomatous component (haemangioma) and a recent sweat-gland growth may be responsible for the appearance of this type and we think that this picture is more frequent but unidentified because, to our knowledge, it was not described up to the present paper.
