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1

Evaluation of the SPECT radioisotope perfusion scan in the detection of ischemic heart disease

Zdanowski Paweł, Cacko Marek, Rabczenko Daniel, Kochman Janusz, Królicki Leszek

Inżynier i Fizyk Medyczny

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2022

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Vol. 11, nr 2

129--135

EN

Objectives: The aim of the study is to determine the diagnostic value of myocardial perfusion scintigraphy (MPS) depending on the location and size of stenosis of a coronary vessel or vessels. Methods: Results of examinations of patients hospitalized in two hospital departments of the same medical facility were analyzed. Retrospective research material consisted of results obtained for 200 patients with suspected ischemic heart disease (coronary artery disease - CAD). From this group, 83 examinations were selected where results of coronary angiography and perfusion scintigraphy (MPS) were available. The following tests were used for statistical studies: t-Student, Chi2, Fisher- -Sendecor, Kruskal-Wallis and Willcoxon. The use of these tests allowed for: – determination of predictive factors favoring development of ischemic heart disease in the analyzed group of patients, – determination of sensitivity and specificity of MPS, taking the coronary examination as the “gold standard”, – assessment of usefulness of the MPS imaging depending on location of a stenosis within the main coronary vessels, – evaluation of usefulness of MPS in detection of a multivessel disease. Results: I n t he a nalyzed g roup o f p atients, a rterial h ypertension was the main factor predisposing to CAD (p = 0.016). The highest sensitivity of MPS in the diagnosis of ischemia was found in the group of patients with stenosis of the right coronary artery (RCA) (p = 0.029) and the circumflex (Cx) and marginal (MB) branches (p = 0.028). A comparative analysis was performed between the degree of narrowing of the above vessels and the degree of perfusion disorders in the MPS study. There was a correlation between the severity of ischemia in MPS and the degree of stenosis in both RCA (p = 0.011, 95% sensitivity (83.1 - 99.4 CI; negative predictive value 83.3%) and the Cx/MB complex (p = 0.044, sensitivity 94.7% ( 83.1 - 99.4 CI), negative predictive value - 83.3%). There was a correlation between the result of the MPS perfusion scan and disease of two or three coronary vessels. There was a 97% agreement between the presence of permanent or transient defects in MPS and the presence of stenosis in 2 or 3 coronary vessels exceeding 80% of the vessel lumen. In the group of patients with stenosis ranging between 50-80%, abnormal results of the MPS occurred in 41.7% of patients. Conclusion: The results confirm that myocardial perfusion scintigraphy is a very valuable screening test in patients with suspected CAD. This examination shows high sensitivity also in the group of patients with multivessel disease.

2

Multi-molecule imaging and inter-molecular imaging in nuclear medicine

Shimazoe Kenji, Uenomachi Mizuki

Bio-Algorithms and Med-Systems

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2022

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Vol. 18, no. 1

127--134

EN

Multi-molecule imaging and inter-molecular imaging are not fully implemented yet, however, can become an alternative in nuclear medicine. In this review article, we present arguments demonstrating that the advent of the Compton positron emission tomography (Compton-PET) system and the invention of the quantum chemical sensing method with double photon emission imaging (DPEI) provide realistic perspectives for visualizing inter-molecular and multi-molecule in nuclear medicine with MeV photon. In particular, the pH change of InCl3 solutions can be detected and visualized in a three-dimensional image by combining the hyperfine electric quadrupole interaction sensing and DPEI. Moreover, chemical states, such as chelating, can be detected through angular correlation sensing. We argue that multi-molecule and chemical sensing could be a realistic stream of research in future nuclear medicine.

3

Program zapewnienia kontroli jakości w medycynie nuklearnej. Testy podstawowe kontroli jakości planarnych kamer scyntylacyjnych oraz kamer SPECT i SPECT/CT

Matuszewski Krzysztof, Szweda Hubert, Cegła Paulina

Inżynier i Fizyk Medyczny

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2019

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Vol. 8, nr 4

279--287

PL

Regulacje prawne oraz zalecenia obligujące do tworzenia systemu kontroli jakości w medycynie nuklearnej mają na celu zapewnienie odpowiedniego poziomu jakości badań diagnostycznych. Podstawowe testy kontroli jakości są ważną częścią rutynowej pracy klinicznej. Celem niniejszej pracy jest przedstawienie procedur testów podstawowych kontroli jakości dla planarnych kamer scyntylacyjnych oraz systemów SPECT i SPECT/CT.

EN

Regulations and recommendations that oblige to create a system of quality assurance in nuclear medicine, provide a sufficient level of quality diagnostic tests. The basic quality control tests are important part of routine clinical work. The aim of the work is to present quality control procedures for planar cameras and SPECT and SPECT/CT systems.

4

Diagnostyka obrazowa okiem neurologa

Leksa Natalia, Truszkiewicz Adrian, Aebisher David, Bartusik-Aebisher Dorota

Inżynier i Fizyk Medyczny

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2019

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Vol. 8, nr 5

363--370

PL

W diagnostyce chorób układu nerwowego dostępne jest szerokie spektrum metod diagnostycznych. Niektóre są wykonywane powszechnie, inne tylko w ośrodkach specjalistycznych. W opracowaniu poniżej omówiliśmy badania obrazowe stosowane w diagnostyce chorób neurologicznych. Szeroko omówiona diagnostyka w kontekście neurologicznym pozwala na uwypuklenie potrzeb, jakie istnieją w tym zakresie z punktu widzenia lekarza neurologa. Pokazano również wartości różnych badań dla różnych schorzeń neurologicznych. Praca ta nie może wyczerpać tematu, jakim jest diagnostyka obrazowa okiem neurologa, ze względu na rozległość tematyki. Założeniem jej jest dokonanie przeglądu dostępnych metod obrazowania i ukazanie ich wartości w leczeniu pacjentów.

EN

A wide spectrum of diagnostic methods are available in the diagnosis of nervous system diseases. Some are commonly performed, others only in specialist centers. In the study below, we discussed imaging tests used to diagnose neurological diseases. The broadly discussed diagnostics in the neurological context allow to highlight the needs that exist in this regard from the point of view of the neurologist. The values of various studies for various neurological diseases are also shown. This work cannot exhaust the topic of diagnostic imaging through the eyes of a neurologist due to the extent of the subject. Its assumption is to review the available imaging methods and show their value in treating patients.

5

Radiofarmaceutyki w Instytucie Chemii i Techniki Jądrowej

Walczak R., Halik P., Gawęda W., Dziawer Ł., Gumiela M.

Postępy Techniki Jądrowej

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2018

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z. 2

41--47

PL

Instytut Chemii i Techniki Jądrowej jest jedną z nielicznych placówek w Polsce, w których prowadzone są badania nad otrzymywaniem nowych radiofarmaceutyków. Prace w tym zakresie prowadzi Pracownia Badań i Syntezy Radiofarmaceutyków pod kierownictwem prof. dr hab. Aleksandra Bilewicza. Tematyka prowadzonych badań jest ukierunkowana na opracowanie nowych metod produkcji radionuklidów oraz sposobów ich dostarczania do miejsc zmian patologicznych w organizmie człowieka. W artykule przedstawiono opisy badań realizowanych przez doktorantów tej Pracowni w ramach prac doktorskich. Wśród tych prac należy wymienić nanonośniki dla emiterów promieniowania alfa, badania nad inhibitorami cholinoesteraz, nowe metody wytwarzania 99mTc i 43Sc czy produkcję radiofarmaceutyków teranostycznych.

EN

The Institute of Nuclear Chemistry and Technology is one of the few institutions in Poland, where research on the acquisition of new radiopharmaceuticals is being conducted. The work in this area is carried out by the Laboratory of Research and Synthesis of Radiopharmaceuticals under the supervision of prof. dr hab. Aleksander Bilewicz. The research is focused on the development of new methods of radionuclide production and methods of their delivery to pathological changes in the human body. The article presents descriptions of research carried out by doctoral students as part of their theses. These include the nanocarriers for alpha-emitters, the study of cholinesterase inhibitors, new methods for the production of 99mTc and 43Sc, as well as the production of teranostatic radiopharmaceuticals.

6

Zastosowanie metod medycyny nuklearnej w diabetologii

Uliński R., Data M., Jarzębowska A., Kocemba M., Górska M., Chojnowski M., Płazińska M. T., Królicki L.

Inżynier i Fizyk Medyczny

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2018

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Vol. 7, nr 4

255--260

PL

Cukrzyca jest chorobą wieloukładową, charakteryzującą się niedoborem insuliny lub opornością tkanek na działanie insuliny, które prowadzą do stanów hiperglikemii. W przebiegu długotrwałej cukrzycy dochodzi do upośledzenia licznych funkcji organizmu oraz uszkodzenia narządów na skutek mikro- i makroangiopatii. Proces ten ma charakter postępujący i wieloletni. Patologiczne zmiany na poziomie mikroskopowym zaczynają się kilka miesięcy lub nawet kilka lat przed kliniczną manifestacją choroby. W tym okresie diagnostyka tego typu zaburzeń przy użyciu klasycznych metod obrazowania jest niezwykle trudna, a czasem niemożliwa. Metody radioizotopowe, obrazując procesy zachodzące na poziomie komórkowym, pozwalają na bardzo wczesną diagnostykę procesów chorobowych występujących w przebiegu cukrzycy.

7

Accuracy of the electrodes location method for simultaneous SPECT and EEG examinations

Kowalczyk L., Goszczyńska H., Zalewska E.

Biocybernetics and Biomedical Engineering

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2015

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Vol. 35, no. 3

176--184

EN

A simultaneous SPECT and EEG examination allows for a combined analysis of brain structural and functional changes. The examinations can be visualized as 3D maps of overlapping SPECT (radiopharmaceutical concentration) and EEG (bioelectric potential) data. Synchronization of both maps is difficult, as SPECT shows neither the skull outline nor the EEG electrodes. Thus a technique to reflect electrodes placement in SPECT data was needed. Earlier we devised a method to make a small number of electrodes visible in SPECT without compromising SPECT accuracy. We also proposed a procedure approximating coordinates of the 10–20 system EEG electrodes in a 3D space using only 5 electrodes coordinates, while assuming that all electrodes are placed on 9 intersecting ellipses. Here we used 20 phantoms of real heads from the BrainWeb project and the Oostenveld calculation of electrodes canonical placement in an averaged head model. We divided the electrodes placement error into an easy-to-assess ‘‘distance error’’ (distance from the head surface) and a difficult-to-assess ‘‘angular error’’ (a wrong direction in relation to the symbolic head center). Applying our procedure to the Oostenveld data set, we assessed the ratio between the distance and the angular error and showed that a majority part of the entire approximation error results from the distance error. Our approximation procedure was applied to the BrainWeb phantoms and the distance error was computed allowing estimation of the entire error of electrodes placement. The estimated average error of the electrodes coordinates' approximation procedure was 4.2 mm and the maximum error was 15.4 mm.

8

Preparation and anatomical distribution study of 67Ga-alginic acid nanoparticles for SPECT purposes in rainbow trout (Oncorhynchus mykiss)

Heidarieh M., Daryalal F., Mirvaghefi A., Rajabifar S., Diallo A., Sadeghi M., Zeiai F., Moodi S., Maadi E., Sheikhzadeh N., Heidarieh H., Hedyati M.

Nukleonika

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2014

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Vol. 59, No. 4

153--159

EN

Ergosan contains 1% alginic acid extracted from two brown sea weeds. Little is known about the target organs and anatomical distribution of Ergosan (alginic acid) in fi sh. Therefore, feasibility of developing alginic acid nanoparticles to detect target organ in rainbow trout is interesting. To make nanoparticles, Ergosan extract (alginic acid) was irradiated at 30 kGy in a cobalt-60 irradiator and characterized by transmission electron microscopy (TEM) and Fourier transform infrared spectroscopy (FTIR). Results from TEM images showed that particle sizes of irradiated alginic acid ranged from 30 to 70 nm. The FTIR results indicated that gamma irradiation had no signifi cant infl uence on the basic structure of alginic acid. Later, alginic acid nanoparticles were successively labelled with 67Ga-gallium chloride. The biodistribution of irradiated Ergosan in normal rainbow trout showed highest uptake in intestine and kidney and then in liver and kidney at 4- and 24-h post injection, respectively. Single-photon emission computed tomography (SPECT) images also demonstrated target specifi c binding of the tracer at 4- and 24-h post injection. In conclusion, the feed supplemented with alginic acid nanoparticles enhanced SPECT images of gastrointestinal morphology and immunity system in normal rainbow trout.

9

Metody i urządzenia do diagnostyki serca

Pałko T.

Inżynier i Fizyk Medyczny

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2013

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Vol. 2, nr 4

169--174

PL

W artykule opisano główne choroby serca i naczyń krwionośnych oraz nowoczesne techniki ich badania. Przedstawiono elektrokardiografię, polifizjografię, metody pomiaru ciśnienia krwi, techniki obrazowania struktur i czynności serca i naczyń, w tym rentgenografię, echoultrasonografię, techniki scyntygrafii radioizotopowej oraz tomografii komputerowej (XCT, MRI, SPECT, PET, tomografie multimodalne). Przedstawiono wnioski i wskazano na potrzebę wzajemnej współpracy lekarzy, fizyków i inżynierów medycznych dla dalszego efektywnego rozwoju metod i technik diagnozowania chorób układu krążenia.

EN

In the paper the main heart and vessel diseases were described, as well as modern technologies of their examination. There were presented techniques such as: electrocardiography, polyphysiography, blood pressure measurement methods, heart and vessel structure and activity imaging methods. Particularly, the X-ray radiography, echoultrasonography and several methods of computed tomography (XCT, MRI, SPECT, PET, multimodal tomography), were described. It was indicated that close cooperation between medical doctors, medical physicists and engineers is needed for progress in diagnostic methods in cardiology and medicine.

10

The effect of type of filters and collimators on the SPECT axis of rotation error

Sadremomtaz A., Taherparvar P., Saiad H.

Biocybernetics and Biomedical Engineering

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2013

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Vol. 33, no. 3

156--163

EN

High resolution and artifact free SPECT reconstruction of the distribution of radioactive sources over the entire imaging field requires exact alignment between the electronic and the mechanical axis of rotations. In this paper, the effect of misalignment between the electronic and the mechanical axis of rotations of SPECT system equipped with low-energy high-resolution and low-energy general-purpose collimators through the field of view has been studied. In addition, the useful dimensions of the SPECT field of view without artifact due to axis of rotation error have been calculated. Furthermore, the roles of digital filters in reducing this effect have been studied.

11

Integration of EEG and SPECT data acquired from simultaneous examinations

Kowalczyk M., Bajera A., Goszczynska H., Zalewska E., Krolicki L.

Biocybernetics and Biomedical Engineering

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2013

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Vol. 33, no. 4

196--203

EN

The aim of this study was to develop a convenient method for superimposing SPECT images and EEG maps. This work was performed as part of research concerning feasibility of improving the localization of epileptic foci comparing to the standard SPECT examination by applying the technique of EEG mapping. The described method relies on making five EEG electrodes visible in SPECT images, calculating the coordinates of these electrodes in SPECT image space, approximating the coordinates of the remaining electrodes used in EEG recording and then computing a sequence of 3D EEG maps spanning on all the electrodes. An example of visualization of EEG and SPECT data integration was presented. The maximum error of the five base electrodes location was assessed below 10 mm. Assuming the exact placement of the base electrodes the accuracy of the proposed method was estimated below 5.5 mm.

12

System matrix computation for iterative reconstruction algorithms in SPECT based on direct measurements

Borys D., Szczucka-Borys K., Gorczewski K.

International Journal of Applied Mathematics and Computer Science

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2011

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Vol. 21, no 1

193-202

EN

A method for system matrix calculation in the case of iterative reconstruction algorithms in SPECT was implemented and tested. Due to a complex mathematical description of the geometry of the detector set-up, we developed a method for system matrix computation that is based on direct measurements of the detector response. In this approach, the influence of the acquisition equipment on the image formation is measured directly. The objective was to obtain the best quality of reconstructed images with respect to specified measures. This is indispensable in order to be able to perform reliable quantitative analysis of SPECT images. It is also especially important in non-hybrid gamma cameras, where not all physical processes that disturb image acquisition can be easily corrected. Two experiments with an 131I point source placed at different distances from the detector plane were performed allowing the detector response to be acquired as a function of the point source distance. An analytical Gaussian function was fitted to the acquired data in both the one- and the two-dimensional case. A cylindrical phantom filled with a water solution of 131I containing a region of 'cold' spheres as well as a uniform solution (without any spheres) was used to perform algorithm evaluation. The reconstructed images obtained by using four different of methods system matrix computation were compared with those achieved using reconstruction software implemented in the gamma camera. The contrast of the spheres and uniformity were compared for each reconstruction result and also with the ranges of those values formulated by the AAPM (American Association of Physicists in Medicine). The results show that the implementation of the OSEM (Ordered Subsets Expectation Maximization) algorithm with a one-dimensional fit to the Gaussian CDR (Collimator-Detector Response) function provides the best results in terms of adopted measures. However, the fit of the two-dimensional function also gives satisfactory results. Furthermore, the CDR function has the potential to be applied to a fully 3D OSEM implementation. The lack of the CDR in system matrix calculation results in a very noisy image that cannot be used for diagnostic purposes.

13

Wykorzystanie topografii optycznej w nieinwazyjnych badaniach ukrwienia mózgu i jej wstępna weryfikacja techniką SPECT

Kacprzak M., Liebert A., Mączewska J., Fronczewska K., Sawosz P., Toczyłowska B., Królicki L., Maniewski R.

Acta Bio-Optica et Informatica Medica. Inżynieria Biomedyczna

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2010

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Vol. 16, nr 2

173-178

PL

Obserwacja zjawiska napływu i klirensu dożylnych środków kontrastujących jest techniką często stosowaną w diagnostyce medycznej. Zastosowanie w tym celu barwników, których widmo absorpcyjne leży w zakresie bliskiej podczerwieni, może być wykorzystane do badań hemodynamiki mózgu metodą optyczną. Opublikowane w ostatnich latach wyniki badań potwierdzają, że cyrkulacja barwnika ICG (zieleń indocjaninowa) w tkance mózgowej może być wykryta bezinwazyjnie metodą optyczną. W niniejszej pracy zostały przedstawione wstępne wyniki badań uzyskane z wykorzystaniem wielokanałowego sytemu do czasowo rozdzielczych pomiarów optycznych, skonstruowanego w IBIB PAN. Badania z zastosowaniem środka kontrastującego ICG przeprowadzono u osób zdrowych i w grupie pacjentów ze stwierdzonymi średnimi dolegliwościami neurologicznymi. Badania porównawcze zostały wykonane metodą radioizotopową SPECT używaną rutynowo w badaniach ukrwienia mózgu.

EN

Monitoring of inflow and washout of an exogenous contrast agent circulating in the human body is frequently utilized for medical diagnosis. Injection of a absorbing dye in near infrared wavelength region can be applied for estimation of cerebral blood flow or perfusion using optical method. It was reported that ICG (indocyanine green) circulating in the brain can be detected non-invasively on the surface of the human adult head. In the present paper we show results of analysis of time-resolved optical signals measured with the use of the self-constructed brain imager based on previously reported brain oxygenation topography system. The study were curried out on healthy volunteers and patients with mild cerebrovascular disorders after injections of the ICG contrast agent. Obtained results from optical measurements were compared with routinely used SPECT technique.

14

Development of 153Sm-DTPA-rituximab for radioimmunotherapy

Bahrami-Samani A., Ghannadi-Maragheh M., Jalilian A. R., Yousefnia H., Garousi J., Moradkhani S.

Nukleonika

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2009

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Vol. 54, No. 4

271-277

EN

Combining beta-particle effect with therapeutic properties of anti-CD20 monoclonal antibody in lymphomas, Mabthera™ (rituximab) was targeted in this study. The antibody was labeled with 153Sm-samarium chloride (185 MBq) after conjugation with freshly prepared ccDTPA. Conjugated-rituximab was obtained by the addition of 1 ml of a rituximab pharmaceutical solution (5 mg/ml, in phosphate buffer, pH = 7.8) to a glass tube precoated with freshly prepared ccDTPA (0.01–0.1 mg) at 25 degrees centigrade. Sm-153 chloride was obtained by a thermal neutron flux (5 × 1013 nźcm–2źs–1) of an enriched 152Sm2O3 sample, dissolved in acidic media. Radiolabeling was performed in one hour by the addition of DTPA-rituximab conjugate at room temperature. Radiochemical purity of 96% (ITLC) and 98% (HPLC) were obtained for the final radioimmunoconjugate (specific activity = 120 TBq/mmol). The final isotonic 153Sm-rituximab complex was checked by gel electrophoresis for protein integrity retention. Biodistribution studies in normal rats were performed to determine radioimmunoconjugate distribution up to 24 h. SPECT images were also obtained using 103 keV photons up to 48 h.

15

Comparison of different SPECT images analysis methods for inter-hemispheric asymmetry detection in patients with epileptic symptoms

Olejarczyk E., Przytulska M., Bajera A., Królicki L.

Biocybernetics and Biomedical Engineering

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2008

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Vol. 28, no. 4

33-41

EN

The aim of this work was examination of asymmetries in activity of the left and right cerebral hemispheres as well as localization and contouring of the regions of reduced or increased activity on the basis of single photon emission computed tomography (SPECT) images. The mean and standard deviation of normalized intensities inside the contoured areas of images, entropy based on intensity histograms and Chen's fractal dimension were calculated.

16

Preparation and biodistribution of [201Tl](III)vancomycin complex in normal rats

Jalilian A., Hosseini M., Karimian A., Saddadi F., Sadeghi M.

Nukleonika

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2006

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Vol. 51, nr 4

203-208

EN

Thallium-201 (T1/2 = 3.04 days) in Tl+ form was converted to Tl3+ cation in presence of O3 in 6 M HCl controlled by RTLC/gel electrophoresis methods. The final evaporated activity was reacted with vancomycin (VAN) in water to yield [201Tl](III)VAN. The best results were obtained at room temperature in water after 30 min with a radiochemical yield > 99%, after mixing the reactants followed by SPE purification using Si Sep-Pak. The studies showed that thallic ion is mostly incorporated into vancomycin with a radiochemical purity of more than 98 š 1% by RTLC. A specific activity of about 4.14 x 1010 Bq/mmol was obtained. Radiochemical purity and stability of 201Tl-VAN in the preparation and in presence of human serum was determined up to 5.5 days. Biodistribution study of 201Tl(III)-vancomycin in normal rats was performed up to 52 h.

17

Tomografia komputerowa

Stasiak M.

Nowa Elektrotechnika

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2005

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nr 4 (8)

22--23