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The cyclotron production of selected radionuclides using medium energy protons

Thesis (PhD)--Stellenbosch University, 2008. / ENGLISH ABSTRACT: Radiochemical research involving ion exchange chromatography is of paramount
importance to the future of radionuclide production at the Radionuclide Production
Group (RPG) of iThemba LABS. It is required for the production of high-activity
yields of radionuclides to effectively remove impurities and for the safety of the
operators performing such productions. The radiochemical separations of some new
products from their target material, as well as experiments to determine whether
production is viable, are described.
67Ga is currently being produced at the RPG and makes use of zinc targets. With the
production of ultra-pure 67Ga, it was necessary to remove any Fe(III) impurities from
the final product, such that it may be possible to label peptides with this product. The
use of Amberchrom CG161M for this purpose was found to be satisfactory.
Interest was shown in 88Y by an overseas company for the manufacture of sources.
While a method involving extraction of the radionuclide and the ion exchange thereof
using Chelex 100 chelating resin had been published, problems with the production
persisted. Three methods, using ion exchange chromatography, were devised to
produce the radionuclide, with two of them being adopted for production purposes.
Thick-target nuclear data have also recently been accumulated in collaboration with
colleagues from ATOMKI, Debrecen, Hungary.
There is a large demand for 82Sr for the manufacture of 82Sr/82Rb generators for
medical use. A method was developed to manufacture this radionuclide with thicker
(32 g) target material, bombarded in the Vertical Beam Target Station (VBTS), and to
separate 82Sr from its target material with the use of Purolite S950 chelating resin.
68Ge/68Ga generators are becoming increasingly important in the world of
radiopharmaceuticals. A project to develop a local generator was funded by the
Innovation Fund and research was performed to produce 68Ge, such that the generator
could be manufactured. This involved bombarding thicker Ga targets in the VBTS
and performing the chemical separation using AG MP-1 anion exchange resin. The final product was loaded onto generators, although tests performed on different
materials to the ones being marketed are also reported in this work.
A project was initiated to study the cluster radioactive decay of 223Ac via 14C and 15N
emission. To produce 223Ac for these observations, a Th target was bombarded. The
227Pa was separated from the target material using AG MP-1 macroporous anion
exchange resin and used as a source, which decayed to 223Ac. The chemical
separation and the drying of the final product onto a source plate were completed
within approximately 70 minutes from the end of bombardment. The work was
performed in collaboration with JINR, Russia, and University of Milan and INFN,
Italy.
133Ba has a half-life of over 10 years and is an expensive radionuclide to produce. It
has been used in medical and biological studies and there still appears to be a demand
for it. A method was devised, utilizing AG50W-X4 cation exchange resin, to separate
133Ba from its CsCl target material.
Agricultural specialists in the past have shown an interest in 28Mg, to determine the
uptake of the element in fruit. It has long been regarded by some of the local
researchers as an interesting project to investigate. It has been determined that the
product can be produced in reasonable quantities using LiCl target material, with ten
targets being bombarded in series using a 200 MeV proton beam delivered by the
Separated Sector Cyclotron. A method, involving the use of Purolite S950 chelating
resin, was devised to separate 28Mg from its target material. / AFRIKAANSE OPSOMMING: Radiochemiese navorsing, wat ioonuitruiling chromatografie behels, is van uiterste
belang vir die toekoms van die produksie van radionukliede by die
Radionukliedproduksiegroep (RPG) van iThemba LABS. Dit is nodig vir die hoë
aktiwiteit opbrengs van radionuklied produkte om onsuiwerhede te verwyder en vir
die veiligheid van die operateurs wat die produksies moet uitvoer. Die skeiding van
nuwe produkte van hulle skyfmateriaal, sowel as eksperimente om vas te stel of ‘n
produksie uitvoerbaar is, word in die werk beskryf.
67Ga word tans by RPG vervaardig en maak gebruik van sink as skyfmateriaal. Vir
die produksie van “ultra-suiwer” 67Ga was dit belangrik om enige Fe(III)
onsuiwerhede uit die finale produk te verwyder om sodoende peptiede merking te kan
uitvoer. Die gebruik van Amberchrom CG161M hars was voldoende vir dié
eksperiment.
‘n Oorsese maatskappy het belangstelling getoon in 88Y vir die vervaardiging van
bronne. Alhoewel ‘n metode wat die ekstraksie van die radionuklied en die ioonuitruiling
daarvan met die gebruik van Chelex 100 chelerende hars reeds gepubliseer
was, het probleme met die produksie voortgeduur. Drie metodes is opgestel om 88Y te
produseer, waarvan twee van die metodes tans gebruik word vir produksie doeleindes.
Dik-skyf kerndata is ook versamel in samewerking met kollegas van ATOMKI,
Debrecen, Hongarye.
Daar is ‘n groot aanvraag vir 82Sr vir die vervaardiging van 82Sr/82Rb generators vir
mediese doeleindes. ‘n Metode is ontwikkel om die radionuklied te vervaardig van
dikker skyfmateriaal (32 g), in die Vertikale Bundelstasie gebombardeer, en om 82Sr
van sy skyfmateriaal te skei met die gebruik van Purolite S950 chelerende hars.
68Ge/68Ga generators is besig om toenemend belangrik te word in die wêreld van
radiofarmasie. iThemba LABS kry baie navrae om die produk te vervaardig. Die
projek was ook deel van die voorlegging aan die “Innovation Fund” en ‘n manier is
ondersoek om 68Ge te vervaardig, wat benodig word om so ‘n generator te laai. Dik Ga skyfmateriaal word in die Vertikale Bundelstasie gebombardeer en ‘n chemiese
skeiding is uitgevoer deur gebruik te maak van AG MP-1 anioonuitruiling hars. Die
finale produk is op die generators gelaai vir toetsdoeleindes. Toetse is ook op ‘n ander
tipe generator uitgevoer en word in die werk beskryf.
‘n Projek is begin om “cluster” radioaktiewe verval van 223Ac, via 14C en 15N emissie,
te bestudeer. ‘n Th-skyf is met protone gebombardeer om die 223Ac te produseer vir
die eksperiment. 227Pa is vervaardig en geskei van die skyfmateriaal. Dit is gedoen
met die gebruik van AG MP-1 makroporeuse anioonuitruiling hars en drooggemaak
op ‘n bronplaat, waar dit verval het na 223Ac. Die chemiese skeiding en die
droogmaak van die finale produk op ‘n bronplaat is uitgevoer binne 70 minute na
Einde van Bombardering (EVB). Die werk is deel van ‘n samewerking met kollegas
van JINR, Rusland, en die Universiteit van Milaan, sowel as INFN, Italië.
133Ba het ‘n halveertyd van oor die tien jaar en is ‘n duur produk om te vervaardig.
Dit is al gebruik in mediese en biologiese studies en daar is deesdae ‘n redelike
aanvraag daarvoor. ‘n Metode is uitgewerk om 133Ba te skei van die CsCl
skyfmateriaal met die gebruik van AG50W-X4 katioonuitruiling hars.
Spesialiste in landboustudies het in die verlede belangstelling getoon in 28Mg. Dit
word gebruik om die absorpsie van dié element in vrugte te ondersoek. Die produk
kan vervaardig word met die gebruik van LiCl skyfmateriaal: tot soveel as tien skywe
(agter mekaar) word gebombardeer met ‘n 200 MeV protonbundel te iThemba LABS.
‘n Metode, wat Purolite S950 behels, is daargestel om 28Mg van die skyfmateriaal te
skei.

Identiferoai:union.ndltd.org:netd.ac.za/oai:union.ndltd.org:sun/oai:scholar.sun.ac.za:10019.1/21914
Date03 1900
CreatorsVan der Meulen, N. P. (Nicolas Philip)
ContributorsVan der Walt, T. N., Raubenheimer, H. G., Steyn, G. F., Stellenbosch University. Faculty of Science. Dept. of Chemistry ond Polymer Science.
PublisherStellenbosch : Stellenbosch University
Source SetsSouth African National ETD Portal
Languageen_ZA
Detected LanguageEnglish
TypeThesis
Formatix, 165 leaves : ill.
RightsStellenbosch University

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