determination of vanadium in animal tissues by pixe and aas
Post on 02-Aug-2016
219 Views
Preview:
TRANSCRIPT
SHORT COMMUNICATION
Journal of Radioanalytical and Nuclear Chemistry, Vol. 247, No. 1 (2001) 175�178
����������������� �������������������������� ���
W. M. Kwiatek,1 B. Kubica,1 R. Grybos′′ ,2 M. Kros′′niak,3 E. M. Dutkiewicz,1 R. Hajduk1
1 Institute of Nuclear Physics, Cracow, Poland2Department of Chemistry, Jagiellonian University, Poland
3Department of Molecular Biology, Jagiellonian University, Poland
(Received February 21, 2000)
Proton induced X-ray emission (PIXE) and atomic absorption spectroscopy (AAS) were used for vanadium determination in animal tissues. The
vanadium concentration levels were determined in blood, kidneys and livers taken from rats. Two groups of the animals were treated with different
diets. The diet for the first group was supplemented with vanadium compounds while the diet for the second one was assumed to be a �normal�
diet. The second group was treated as control. In order to achieve the best minimum detectable limit (MDL)1 the samples were subject to a special
sample preparation procedure. Blood and kidneys were mineralized with an APDC compound. The mineralization process was performed
according to the procedure described previously.2 The application of PIXE3 is very useful for different types of samples. PIXE measurements were
performed with a proton beam at the Institute of Nuclear Physics in Cracow, Poland while the AAS measurements were done at the Institute of
Molecular Biology, Jagiellonian University, Poland. The concentration levels of vanadium in blood and kidneys are compared and discussed.
There were no significant statistical differences between results of vanadium concentration levels determined by the abovementioned techniques.
The PIXE technique had the advantage over the AAS technique of giving a broad spectrum of trace elements analyzed in a single measurement.
Therefore with the help of sample preparation procedure the application of the PIXE method seems to be suitable for such analyzes.
Introduction
Vanadium is a trace element widely distributed in the
environment. It is a contaminant of many ores, petroleum
oils, coals, and used in the steel and chemical
industries.4 It is present at trace level in various sources
for nutrition such as meat, fish, vegetables, milk, etc.5,6
from which it is taken up by animals and humans.
Vanadium has been shown to produce several important
biological effects in living organisms.7�9 The insulin-
mimetic action of vanadium both in vitro and in vivo has
been demonstrated in numerous studies.8,10�12 Its
therapeutic potential has been shown in clinical studies
with diabetic patients.13,14
It has been estimated that no more than 1% of
vanadium normally taken up with the diet is absorbed.15
The concentration of vanadium (ng/g dry tissue weight)
in tissues of nonsupplemented rats depends on the organ
in the order: brain (2 ng/g) < fat < blood < heart <
muscle < lung < liver < testes < spleen < kidney
(133 ng/g).16 All organs accumulate vanadium in a
dose16 and type of compound manner.17
Vanadium in body fluids and tissues can be determined
by various methods such as: atomic absorption spectrometry
(AAS),18,19 voltametry,20 inductively coupled plasma
atomic emission spectrometry (ICPAES),21 inductively
coupled plasma mass spectrometry (ICPMS),22 neutron
activation analysis (NAA),23 and 48V-radiolabeled tracer.17
Comprehensive overviews on vanadium determination in
biological materials have been published24 and it seems that
PIXE has not been applied yet for this purpose. Therefore,
the authors have applied that technique since it has been
recognized as a multi-elemental analytical method.
Experimental
The experiment was carried out on male Wistar rats,
weighting 150±29 g. Animals were housed in wire cages
in a room at 20±2 °C with natural light-dark cycles. The
animals were allowed free access to commercial pelleted
food and tap water. The rats were divided into control
and vanadium treated (VT) groups. The animals in group
VT received bis (1,10-phenanthroline) oxovanadium
(IV) sulphate trihydrate (VO(phen)2SO4.3H2O)
suspended in 1% methylcellulose by one-time oral dose
of 200 mg/kg of rat. Bis (1,10-phenanthroline)
oxovanadium (IV) sulphate trihydrate was prepared by
the modified method described in the literature.25 Two
days after the administration of vanadyl complex the rats
were exanguinated under light ether anesthesia before
sacrificing. Then the samples of blood, kidney and liver
were taken out from the animals frozen at �20 °C and
dried at 55 °C to constant mass.
Sample preparation procedure
Mineralization procedure: High purity compounds as
HNO3, H2O2, and APDC (ammonium pyrrolidine-
dithiocarbomate) were used. Nitric acid was additionally
purified by means of distillation. Samples were treated
with HNO3, H2O2 for 20 minutes at 1200 °C. When they
were fully mineralized the solution was divided into two
parts. One was analyzed by atomic absorption
spectroscopy (AAS) and APDC compound was added to
the second one in order to form complexes with metals
that exist in the samples. The solution was filtered
0236�5731/2001/USD 17.00 Akadémiai Kiadó, Budapest
© 2001 Akadémiai Kiadó, Budapest Kluwer Academic Publishers, Dordrecht
W. M. KWIATEK et al.: DETERMINATIONOFVANADIUM INANIMALTISSUESBY PIXE ANDAAS
through a Millipore filter GVWP 22. The undiluted
complexes were left on the filter and then the filter was
dried at 50 °C for 1 hour. The prepared filters were the
targets in PIXE analysis for the determination of trace
element concentration.
Normal preparation procedure: Samples were dried
for 24 hours at 50 °C and then powdered in an agate
mortar. Then the samples were pressed into pellets of
10 mm in diameter and 1 mm thick. Such a pellet was
placed on Scotch tape and fixed to an aluminum frame.
Then the frames were put into the chamber and analyzed
by PIXE.
Methods and apparatus
The PIXE method was applied in the Institute of
Nuclear Physics in Cracow. A proton beam of 2.5 MeV
from the Van de Graaff accelerator was used for these
analyses. Both types of samples (filters and pellets) were
analyzed for 15 minutes in order to get good statistics in
the X-ray characteristic spectra. The spectra were
detected with a Si(Li) detector with an energy resolution
of 160 eV for 5.9 keV X-rays. For normalization
backscattered protons were used. All the spectra
(characteristic X-rays and particle spectra) were
registered with an ADCAM system.
The AAS measurements were performed at the
Institute of Molecular Biology, Jagiellonian University.
A Perkin Elmer 5100 ZL apparatus with Zeeman
background correction device was used for vanadium
content determination. The measurements were done by
non-flame absorption spectrometry. The samples were
injected into a graphite tube.
Results and discussion
The results obtained from both techniques are
presented in Tables 1 and 2. Table 1 presents vanadium
concentration levels in samples taken from both rat
groups. The concentrations are given in µg/g dry mass.
In these tables the results from PIXE and AAS are
compared.
As seen in Table 1 there is no statistical difference
between the concentration levels determined with the
two techniques. But the application of PIXE enabled the
multi-elemental determination shown in Table 2. For
determination of trace element concentration levels the
IAEA standards were used. Those standards include:
H-4 - animal muscle, H-8 horse kidney, and A-13 animal
blood.
Table 1. Vanadium concentration levels determined by PIXE and AAS in rat samples (µg/g dry mass)
Sample Vanadium concentration Vanadium concentration
determined by AAS determined by PIXE
Bt 0.195 ± 0.029 0.078 ± 0.019
Vt 1.167 ± 0.187 2.133 ± 0.457
Bn 0.548 ± 0.093 0.457 ± 0.192
Vn 2.787 ± 0.371 2.237 ± 0.095
Bk 0.344 ± 0.043 0.444 ± 0.067
Vk 1.537 ± 0.199 1.490 ± 0.568
Bt � liver from control group of rats,Vt � liver from vanadium treated rats,Bn � kidney from control group of rats,Vn � kidney from vanadium treated rats,Bk � blood from control group of rat,Vk � blood from vanadium treated rats.Estimated errors for AAS are about 15%.
Table 2. Trace element concentration levels determined by PIXE
Sample V Mn Fe Cu Zn Pb Se Br
Bt 0.078 ± 0.019 0.622 ± 0.071 267 ± 45 61.6 ± 6.9 231 ± 30 17.9 ± 2.5 2.0 ± 0.5 0.089 ± 0.010
Vt 2.133 ± 0.457 4.438 ± 0.567 75 ± 15 68.0 ± 8.0 60 ± 15 2.8 ± 3.5 1.9 ± 0.5 0.209 ± 0.040
Bn 0.457 ± 0.192 0.906 ± 0.112 1180 ± 360 324 ± 46 538 ± 55 22.4 ± 2.8 8.4 ± 1.5 0.163 ± 0.035
Vn 2.239 ± 0.095 4.744 ± 0.596 5090 ± 820 80 ± 25 51.5 ± 6.5 69 ± 9.5 4.4 ± 0.9 2.316 ± 0.350
Bk 0.444 ± 0.067 2.723 ± 0.382 2930 ± 330 53 ± 15 16.1 ± 2.2 24.0 ± 4.0 2.6 ± 0.7 0.533 ± 0.200
Vk 1.490 ± 0.568 0.785 ± 0.142 482 ± 95 150 ± 25 36.7 ± 4.8 6.3 ± 0.9 9.8 ± 3.5 0.171 ± 0.035
Bt � liver from control group of rats,Vt � liver from vanadium treated rats,Bn � kidney from control group of rats,Vn � kidney from vanadium treated rats,Bk � blood from control group of rat,Vk � blood from vanadium treated rats.
176
W. M. KWIATEK et al.: DETERMINATIONOFVANADIUM INANIMALTISSUESBY PIXE ANDAAS
Figures 1 and 2 show PIXE spectra of kidney and
blood samples. Spectra (a) correspond to samples with
no vanadium treatment while spectra (b) relate to the
samples treated with vanadium compounds. The spectra
do not differ in elemental composition. There is a
significant difference in vanadium peak intensity. Figure
3 shows two spectra of the same blood sample. Spectrum
(a) corresponds to the thick sample while spectrum (b)
corresponds to the sample prepared by the
mineralization procedure. As seen in the case of
spectrum (b), the calcium and potassium peaks are
reduced in comparison to those in spectrum (a). This
reduction is due to the application of APDC.
Conclusions
PIXE analysis is very sensitive to multi-trace element
determinations. The advantage of this technique is its
multi-elemental character at the time while the AAS
technique gives more precise results but each element
has to be determined separately. In order to increase the
sensitivity of PIXE, the mineralization procedure of the
sample is very useful and helps to achieve a better
determination at lower levels.
Fig. 1. The PIXE spectra of kidney sample: a � thick target,
b � thin target that followed mineralization procedure
Fig. 2. The PIXE spectra of blood sample: a � thick target,
b � thin target that followed mineralization procedure
Fig. 3. The PIXE spectra of blood sample: a � thick target,
b � thin target that followed mineralization procedure
177
W. M. KWIATEK et al.: DETERMINATIONOFVANADIUM INANIMALTISSUESBY PIXE ANDAAS
*
This work was supported by KBN Grant No. 8 T11E 017 16.
References
1. L. A. CURIE, Anal. Chem., 40 (1968) 586.
2. B. KUBICA, W. M. KWIATEK, E. DUTKIEWICZ, M. LEKKA,
J. Radioanal. Nucl. Chem., 223 (1997) 247.
3. U. LINDH, P. FRISK, J. NYSTROM, A. DANERSUD, R. HUDECEK,
A. LINDVALL, S. THUNELL, Nuclear Instr. Meth. Phys. Res., B
130 (1997) 406.
4. ATSDR, Agency for Toxic Substances and Disease Registry:
Toxicological Profile for Vanadium and Compounds, U.S. Public
Health Service, Atlanta, 1991.
5. H. A. SCHROEDER, J. J. BALASSA, I. H. TIPTON, J. Chronic. Dis.,
16 (1963) 1047.
6. R. SOREMARK, J. Nutr., 92 (1967) 183.
7. W. DABROS′ , A. M. KORDOWIAK, D. DZIGA, R. GRYBOS′ , Pol.J. Pathol., 49 (1998) 67.
8. H. SIGEL, A. SIGEL (Eds), Metal Ions in Biological Systems,
Vol. 31, Marcel Dekker, New York, 1995, Chapters 8�18 and
references therein.
9. S. VERMA, M. C. CAM, J. H. MCNEILL, J. Am. Coll. Nutr.,
17 (1998) 11.
10. A. M. KORDOWIAK, R. TRZOS, R. GRYBOS′ , Horm. Metab. Res.,
29 (1997) 101.
11. M. B. RHONDA, G. H. FREDERICK, Int. J. Pharm., 183 (1999) 117.
12. P. POUCHERET, S. VERMA, M. C. GRYNPAS, J. H. MCNEILL, Mol.
Cell. Biochem., 188 (1998) 8.
13. A. B. GOLDFINE, Dc. SIMONSON, F. FOLLI, M. E. PATTI,
C. R. KAHN, J. Clin. Endokrinol. Metab., 80 (1995) 3312.
14. Z. W. YU, P. A. JANSSON, B. I. POSNER, U. SMITH,
J. W. ERIKSSON, Diabetologia, 40 (1997) 1197.
15. L. L. HOPKINS Jr, B. E. TILTON, Am. J. Physiol., 211 (1966) 169.
16. F. G. HAMEL, W. C. DUCKWORTH, Mol. Cell. Biochem.,
153 (1995) 95.
17. I. A. SETYAWATI, K. H. THOMPSON, V. G. YUEN, Y. SUN,
M. BATTELL, D. M. LYSTER, C. VO, T. J. RUTH, S. ZEISLER,
J. H. MCNEILL, C. ORVIG, J. Appl. Physiol., 84 (1998) 569.
18. V. G. YUEN, C. ORVIG, K. H. THOMPSON, J. H. MCNEILL, Can.
J. Physiol. Pharmacol., 71 (1993) 270.
19. J. L. DOMINGO, M. GOMEZ, J. M. LJOBET, J. CORBELLA,
C. L. KEEN, Toxicology, 66 (1991) 279.
20. J. WANG, B. TIAN, J. LU, Talanta, 39 (1992) 39.
21. A. K. SAXENA, P. SRIVASTAVA, N. Z. BAQUER, Eur.
J. Pharmacol., 216 (1992) 123.
22. J. YAO, M. L. BATTELL, J. H. MCNEILL, Can. J. Physiol.
Pharmacol., 75 (1997) 83.
23. F. G. HAMEL, S. S. SOLOMON, A. S. JESPERSEN, A. BLOTCKY,
E. RACK, W. C. DUCKWORTH, Metabolism, 42 (1993) 1503.
24. H. G. SEILER, in: Metal Ions in Biological Systems, Vol. 31,
H. SIGEL and A. SIGEL (Eds), Marcel Dekker, New York, 1995,
p. 671 and references therein.
25. J. SELBIN, L. H. HOLMES Jr., J. Inorg. Nucl. Chem., 24
(1962) 1111.
178
top related