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Nuclear Science and Technology | Progress Report 165
using compact XRF spectrometers
its elemental composition was investigated
using Neutron Activation Analyses technique The use of analytical techniques to investi-
(NAA). The measurements were performed gate specific ions in body fluids has increase
in the IEA-R1 nuclear reactor (IPEN/CNEN-SP, in last year’s presenting significant progress
Brazil). The elements Cl and Na were identi- in clinical tests. This motivated us to check
fied as majorities while the presence of As, Ca, the performance of two compacts XRF spec-
Cr, Fe and S were also observed, but in small trometers, consisting of Ag and Au X-ray mini-
concentration (μg/L). These data can be used tubes associated with a Si Drift detector with
to standardize a specific antilonomic serum Be window (12.5μm) for this clinical finality.
for caterpillars (L. obliqua) coming from dif- Using the Energy Dispersive X-Ray Fluores-
ferent regions of Brazil. cence technique (EDXRF), specific ions of clin-
ical relevance, such as, Ca, Cl, Fe and K were
Characterization of inorganic elements investigated using standards (certified solu-
in coxal fluid of Ornithodoros tions). The performance of these spectrom-
brasiliensis (Acari: Arrgasidae) eters were checked by evaluation of several
parameter (linearity, reproducibility, accura-
Ornithodoros brasiliensis tick has distribu- cy, precision, sensitivity and detection limit)
tion restricted to the State of Rio Grande do Sul usually considered for validation procedures
(São Francisco de Paula). Due to its quick en- on analytical methods, according to ISO 17025
gorgement, hydrostatic balance is maintained and EURACHEM/CITAC norms. The method
through the secretion of excess body fluids was proved to give reliable results with lim-
and ions in the coxal liquid (CL) by coxal gland, its of detection at levels of 0.23 to 0.58 mgL−1.
during and after feeding. The biochemical and Considering that the ranges of the body fluids,
ionic compositions are unknown; moreover, re- such as: blood, saliva, serum and urine, are in
cent investigations suggest that there are some the order of hundreds of mg L-1, this proce-
molecules able to help the tick in anti-haemo- dure is very promising for ions dosage requir-
static strategies. The aim of this study was to ing a small amount of sample (50μL, 10 times
determine the elemental composition of the less comparatively to the conventional tests),
coxal liquid of this tick using NAA. The liquid simultaneous analysis, short time of analysis
was collected during and after tick feeding; (minutes) and simple sample preparation. In
the ticks feed on rabbits (Oryctolagus cunicu- addition, this procedure offers a non-destruc-
lus). The NAA measurements were performed tive alternative for clinical usage.
in the IEA-R1 nuclear reactor at IPEN/CNEN-
SP (3-4.5MW, pool type). These measurements These compact spectrometers have also po-
revealed high concentrations of Na, Cl and S tential use when the biological material is
suggesting the association with osmotic pres- scarce, case of the pediatric practice in new-
sure regulation mechanisms during tick feed- borns and premature infants (blood collection
ing and the presence of Br, Mg, K, P and Ca as is the main cause of transfusions) and in vivo
trace. The data are crucial for appropriate pu- tests, in small size animal model (mice and
rification and characterization of the relevant rats), in order to evaluate the safety of new
proteins in this secretion. drugs, vaccines and others medical supplies.
Quantitative analysis of light elements Determination of iron supplementation
(Z<26) in serum and whole blood in food fortification using X-ray