Self-radiation induced exchange between tritiated water and organic compounds. The labelling of L-chiro-inositol, myo-inositol and Hexa-O-methyl-L-chiro-inositol

1975 ◽  
Vol 28 (9) ◽  
pp. 1981 ◽  
Author(s):  
DHT Fong ◽  
CL Bodkin ◽  
MA Long ◽  
JL Garnett

The stereochemistry of the tritiation of L-chiro-inositol, myo-inositol and hexa-O-methyl-L-chiro-inositol by self-radiation induced exchange with tritiated water of high specific activity has been investigated. Predominance of configurational retention was found to accompany tritium labelling in the two inositols, while substantial configurational inversion occurred in the hexa-O-methyl derivative. Tritiation occurred predominantly at C 1 in L-chiro-inositol, with slight inversion at this position alone accompanying the labelling. Comparison with Wilzbach T2 gas exposure results indicates the HTO method yields less by-products, myo-inositol having a radiochemical purity of 97%.

1980 ◽  
Vol 26 (1) ◽  
pp. 159-162 ◽  
Author(s):  
J Sophianopoulos ◽  
I Jerkunica ◽  
C N Lee ◽  
D Sgoutas

Abstract We describe an ultrafiltration technique for rapidly and directly determining free triiodothyronine or free thyroxine, or both. After equilibrating serum at 37 degrees C with purified tracer of high specific activity, we placed 0.15 mL of serum in 2.8 mL of phosphate buffer (0.1 mol/L, pH 7.4) in the ultrafiltration cell and obtained successive 0.2- and 0.6-mL fractions of protein-free ultrafiltrate. Under our conditions free ligand concentration was independent of flow rate. After purifying the second fraction with protein-coated charcoal, we could determine the proportion of free triiodothyronine or free thyroxine. Samples from normal adult men and women, including women who were taking oral contraceptives or were pregnant, and from hypo- and hyperthyroid patients gave results that agreed with those obtained by equilibrium dialysis. Speed is the main advantage of the method: one technologist can complete the procedure in 2 h and, using a multi-micro-ultrafiltration system, can process many samples in one day. For laboratories where index-type reactions are performed routinely and direct free triiodothyronine or free thyroxine is determined only on selected specimens, this method is superior to dialysis. It is also very convenient for rapidly purifying tracers, to at least 97% radiochemical purity, with 94% recovery and no dilution.


2015 ◽  
Vol 16 (1) ◽  
pp. 29
Author(s):  
Azmairit Aziz ◽  
Nana Suherman

ABSTRAK KARAKTERISASI FISIKO-KIMIA RADIOISOTOP 149Pm HASIL IRADIASI BAHAN SASARAN 148Nd ALAM. Penyakit kanker merupakan salah satu masalah utama yang dihadapi Indonesia di bidang kesehatan. Radioisotop pemancar-β- dengan aktivitas jenis tinggi dapat digunakan untuk penandaan biomolekul sebagai radiofarmaka spesifik target untuk terapi sel kanker. Promesium-149 (149Pm) merupakan salah satu radiolantanida pemancar-β- yang me-miliki energi beta (Eβ-)maksimum sebesar 1,07 MeV (95,9 %) dan dapat dipertimbangkan untuk digunakan pada terapi kanker berdasarkan sifat nuklir yang dimilikinya. Radioisotop 149Pm dapat dibuat dengan cara tidak langsung melalui reaksi inti (n,γ) di reaktor nuklir menggunakan bahan sasaran isotop 148Nd (neodymium-148) dan radioisotop 149Pm yang dihasilkan adalah bebas pengemban (carrier free) sehingga memiliki aktivitas jenis tinggi. Pada penelitian ini digunakan bahan sasaran Nd2O3 alam yang diiradiasi selama ± 4 hari di Central Irradiation Position (CIP) RSG-G.A.Siwabessy – Serpong pada fluks neutron termal ~1014 n.cm-2.det-1. Radioisotop 149Pm dipisahkan dari bahan sasaran Nd2O3 hasil iradiasi menggunakan metode kromatografi ekstraksi. Larutan radioisotop 149PmCl3 yang dihasilkan dikarakterisasi secara fisiko-kimia meliputi penentuan kemurnian radiokimia menggunakan metode kromatografi kertas dan elektroforesis kertas. Kemurnian radionuklida ditentukan menggunakan spektro-meter-γ dengan detektor HP-Ge yang dilengkapi multichannel analyzer (MCA). Larutan 149PmCl3 yang diperoleh berupa larutan jernih, memiliki pH 2 dan konsentrasi radioaktif 4,2 – 7,4 mCi/mL. Larutan 149PmCl3 memiliki kemurnian radiokimia 99,70 ± 0,23% dan kemurnian radionuklida setelah pendinginan selama 9 hari sebesar 98,58 ± 0,44%. Larutan 149PmCl3 stabil selama 2 minggu pada temperatur kamar. Larutan radioisotop 149PmCl3 memiliki karakteristik fisiko-kimia yang memenuhi persyaratan untuk digunakan dalam pembuatan radiofarmaka ABSTRACT  PHYSICO - CHEMICAL CHARACTERIZATION OF 149Pm RADIOISOTOPE FROM IRRADIATED NATURAL 148Nd TARGET. Cancer is one of the major problems encountered in the field of health in Indonesia. A beta-emitting radioisotope with high specific activity can be used for labeling of biomolecules as a targeted radiopharmaceutical for cancer therapy. Promethium-149 (149Pm) is one of beta-emitting radiolanthanides with beta energy (Eβ-) maximum of 1.07 MeV (95.9%) and can be considered to be used for cancer therapy based on its nuclear properties. Radioisotope of 149Pm can be produced by indirect methode through (n,γ) reaction in nuclear reactor using 148Nd (neodymium-148) target material and 149Pm was produced as a carrier free radioisotope, so that it has high specific activity. In this study, natural Nd2O3 target was irradiated for ± 4 days in central irradiation position (CIP) of RSG-G.A. Siwabessy – Serpong at a thermal neutron flux of ~ 1014 n.cm-2.sec-1. Radioisotope of 149Pm was separated from irradiated of Nd2O3 target using extraction chromatography method. The physico-chemical characterization of 149PmCl3 solution was studied involves the determination of its radiochemical purity using paper chromatography and paper electrophoresis methods. The radionuclide purity was determined using a γ-spectrometer with  HP-Ge detector and coupled with a multichannel analyzer (MCA). 149PmCl3 was obtained as a clear solution, has a pH of 2 and  radioactive concentration of 4.2 to 7.4 mCi/mL. 149PmCl3 solution has radiochemical purity of 99.70 ± 0.23% and radionuclide purity after cooling for 9 days of 98.58 ± 0.44%. 149PmCl3 solution was stable for 2 weeks at room temperature. 149PmCl3 solution has the physico-chemical characteristics that meet requirements for use in preparation of radiopharmaceuticals.


1979 ◽  
Vol 57 (11) ◽  
pp. 1281-1283
Author(s):  
Hiroshi Yamazaki ◽  
Kwok-Luen Leung ◽  
Ann D. E. Feaser

A simple and rapid method for preparing [32P]adenosine 3′,5′-cyclic monophosphate (cAMP) is described. A culture of an Escherichia coli mutant which excretes cAMP about 150 times faster than does a wild-type strain was incubated overnight with [82P]orthophosphate of high specific activity (e.g., 4000 Ci/mol (1 Ci = 37 GBq)). The [32P]cAMP which accumulated extracellularly was then purified to 99.9% radiochemical purity in less than 4 h by adsorption to charcoal and alumina column chromatography. A two-dimensional chromatography system using a PEI-cellulose plate is also described which should prove useful for studying cAMP metabolism with 32P- or 3H-labeled cAMP or ATP.


Author(s):  
Sean S. Tanzey ◽  
Xia Shao ◽  
Jenelle Stauff ◽  
Janna Arteaga ◽  
Phillip Sherman ◽  
...  

Positron emission tomography (PET) imaging of Colony Stimulating Factor 1 Receptor (CSF1R) is a new strategy for quantifying both neuroinflammation and inflammation in the periphery since CSF1R is expressed on microglia. AZ683 has high affinity for CSF1R (Ki = 8 nM; IC50 = 6 nM) and >250-fold selectivity over 95 other kinases and, in this paper, we report the radiosynthesis of [11C]AZ683 and initial evaluation of its use in CSF1R PET. [11C]AZ683 was synthesized by 11C-methylation of the desmethyl precursor with [11C]MeOTf in 3.0% non-corrected activity yield (based upon [11C]MeOTf), >99% radiochemical purity and high specific activity. Preliminary PET imaging with [11C]AZ683 revealed no brain uptake in rodents and nonhuman primates suggesting that [11C]AZ683 is a poor candidate for imaging neuroinflammation, but that it could still be useful for peripheral imaging of inflammation.


1981 ◽  
Vol 36 (5-6) ◽  
pp. 383-384 ◽  
Author(s):  
F. Michael Blaicher ◽  
Kumar D. Mukherjee

Abstract Maturing seeds of Sinapis alba were incubated with D-[U-14C]glucose, sodium [l-14C]acetate or m>>O[U-14C]inositol in order to prepare radioactively labelled phytic acid with high specific activity. Although each substrate was utilized for the biosynthesis of phytic acid, maximum incorporation of radioactivity into phytic acid was found with rayoinositol. Radiochemical purity of the [U-14C]phytic acid preparations was confirm ed by chromatographic techniques. Such preparations should be useful for the study of interaction of phytic acid with metal ions and proteins and may serve as substrate in the assay of phytase.


1966 ◽  
Vol 21 (9) ◽  
pp. 855-858 ◽  
Author(s):  
Hans Emmerich ◽  
Peter Schmialek

A method is described for the preparation of tritiated polycyclic aromatic hydrocarbons with extremely high specific activity in the presence of AlCl3 and HTO. The hydrocarbons are purified by preparative thin layer and paper chromatography. The radiochemical purity of the compounds was proved by paper chromatography and dilution analysis. The following specific activities are reached: Anthracene: 54 Curies/mMol, 7,12-Dimethylbenzanthracene: 19 Curies/mMol, 3,4-Benzopyrene: 24 Curies/mMol, and 3-Methylcholanthrene: 44 Curies/mMol.


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