Purpose: The aim of this study was to determine the selenium content in various tissues of the mouse employing the galvanostatic stripping chronopotentiometry (SCP) technique and to investigate the distribution profile of selenium as well as its pharmacokinetics in a mouse model.
Methods: The animals received 0.25 μg/g Se orally for 5 days. Samples of whole blood and various tissues comprising kidney, liver and brain were harvested from mice and then analysed for Se content employing the SCP technique.
Results: The SCP method was validated over Se concentration range of 10 – 100 ng/mL and showed good linearity (r² > 0.999). The precision (over 5 days) of the assay in various mouse tissues (liver, kidney, and brain) ranged from 0.03 to 2.9% with accuracy results that varied from -6.69 to 0.28%. The mean (n = 5) recoveries of Se from the mouse tissues ranged from 93.31 to 100.28%. The lower limit of Se detection in the mouse tissues was 0.2 ng/mL. The present method was successfully applied in evaluating the distribution of Se in various tissues as well as its pharmacokinetics in the mouse model. The Se tissue concentrations in the mouse model showed that the maximum Se levels in most tissues were attained within 3-4 days following its administration. Furthermore, the pharmacokinetic profile of Se in the mouse model indicates that the element is slowly absorbed from the gastrointestinal tract (GIT) reaching a plateau in 4 days and then it is slowly eliminated from the body with a half-life of about 4.5 days.
Conclusions: The present SCP method was employed to analyse Se in various mouse tissues. The method was characterized by excellent performance parameters necessary for the determination of Se in biological matrices. Se distributes in whole blood as well as into various tissues of the mouse with high concentrations in the kidney and liver and low levels in the blood and brain tissues. The absorption of Se from the GIT was very slow and the data suggest that the elimination of Se seems to be through the kidney at a very slow rate as well. The data of the present study thus suggest that Se remains in the mouse body for a long period of time.