ABSTRACT
Silver nanoparticles (AgNPs) are the most commonly used nanoparticles owing to their antimicrobial properties. The motivation of the present study was (1) to analyze the effect of silver particle size on rat tissue distribution at different time points, (2) to determine the accumulation of AgNPs in potential rat target organs, (3) to analyze the intracellular distribution of AgNPs and (4) to examine the excretion of AgNPs by urine and feces. AgNPs were characterized by dynamic light scattering (DLS), zeta potential measurements, BET surface area measurements, transmission and scanning electron microscopy. AgNPs (20 and 200 nm) were administered intravenously (i.v.) to male Wistar rats at a dose of 5 mg kg(-1) of body weight. Biological material was sampled 24 h, 7 and 28 days after injection. Using inductively coupled plasma-mass spectrometry (ICP-MS) and transmission electron microscopy (TEM) it was observed that AgNPs translocated from the blood to the main organs and the concentration of silver in tissues was significantly higher in rats treated with 20 nm AgNPs as compared with 200 nm AgNPs. The highest concentration of silver was found in the liver after 24 h. After 7 days, a high level of silver was observed in the lungs and spleen. The silver concentration in the kidneys and brain increased during the experiment and reached the highest concentration after 28 days. Moreover, the highest concentration of AgNPs was observed in the urine 1 day after the injection, maintained high for 14 days and then decreased. The fecal level of silver in rats was the highest within 2 days after AgNPs administration and then decreased.
Subject(s)
Metal Nanoparticles/chemistry , Silver/metabolism , Animals , Dose-Response Relationship, Drug , Feces/chemistry , Liver/metabolism , Male , Mass Spectrometry , Metal Nanoparticles/administration & dosage , Microscopy, Electron, Scanning , Microscopy, Electron, Transmission , Rats , Rats, Wistar , Silver/administration & dosage , Tissue DistributionABSTRACT
A graphite furnace atomic absorption method of platinum and palladium determination after their separation from environmental samples has been presented. The samples were digested by aqua regia and the analyte elements were separated on the dithizone sorbent. The procedure of sorbent preparation was described and their properties were established. Two various procedures of elution by thiourea and concentrated nitric acid were described and discussed. The low limit of detection was established as 1ngg(-1) for platinum and 0.2ngg(-1) for palladium. There was also investigated the behaviour of platinum and palladium introduced into the soil in various chemical forms.
ABSTRACT
A new 2-mercaptobenzothiazole loaded Bio-Beads SM-7 resin has been prepared and its analytical properties were established. The sorbent was applied to the separation and preconcentration of inorganic and alkylmercury from natural waters. Optimum conditions of separation as pH, flow rate on column, volume of samples and desorbing agent were established. The cold vapour atomic absorption method determination of both forms of mercury after their successive reduction by tin(II) was used. The low limit of determination for this method was established as 10 ng l(-1) for 1.0 l water sample. Accuracy and precision of the method was estimated by using test water standards and samples of natural water spiked with known amounts of mercury species.
ABSTRACT
A chelating sorbent loaded with dithizone was obtained by chemical reaction with styrene-DVB (5%) copolymer as matrix. The analytical characteristics of the sorbent were established and optimum sorption conditions for Ag, Cu, Cd, Pb, Ni, Co and Zn under static and dynamic conditions determined. The sorbent was applied to determination of copper and lead in river water and of silver in electrolytic copper. After separation of traces of metals on the sorbent and desorption with hydrochloric acid, the metals were determined in the effluent by atomic-absorption spectrophotometry.
ABSTRACT
A chelating sorbent was obtained by deposition of 1-(2-pyridylazo)-2-naphthol on Amberlite XAD-4. The analytical characteristics of the sorbent were established and optimum sorption conditions for Cu, Zn, Fe, Cd, Ni, and Pb under static and dynamic conditions were determined. The sorbent was applied to analysis of river water. After group separation of traces of metals on the sorbent and subsequent elution with hydrochloric add, the metals were determined in the effluent by atomic-absorption spectrophotometry.
