Dry ashing of organic rich matrices with palladium for the determination of arsenic using inductively coupled plasma-mass spectrometry

Effects of Long-Term Dietary Zinc Oxide Nanoparticle on Liver Function, Deposition, and Absorption of Trace Minerals in Intrauterine Growth Retardation Pigs

To investigate the long-term effects of dietary zinc oxide nanoparticle (Nano-ZnO, 20-40 nm) on the relative organ weight, liver function, deposition, and absorption of trace minerals in intrauterine growth retardation (IUGR) pigs, piglets were allocated to NBW (6 normal birth weight piglets fed basal diets), IUGR (6 IUGR piglets fed basal diets) and IUGR+NZ (6 IUGR piglets fed basal diets + 600 mg Zn/kg from Nano-ZnO) groups at weaning (21 days of age), which were sampled at 163 days of age. There were no noteworthy changes in the relative weight of organs, hepatic histomorphology, serum alkaline phosphatase, glutamic pyruvic transaminase and glutamic oxalacetic transaminase activities, and Mn, Cu, and Fe concentrations in leg muscle, the liver, the tibia, and feces among the IUGR, NBW, and IUGR+NZ groups (P>0.05), and no intact Nano-ZnO in the jejunum, liver, and muscle was observed, while dietary Nano-ZnO increased the Zn concentrations in the tibia, the liver, serum, and feces (P<0.05) and mRNA expression of metallothionein (MT) 1A, MT2A, solute carrier family 39 member (ZIP) 4, ZIP14, ZIP8, divalent metal transporter 1, solute carrier family 30 member (ZnT) 1, ZnT4 and metal regulatory transcription factor 1, and ZIP8 protein expression in jejunal mucosa (P<0.05). Immunohistochemistry showed that dietary Nano-ZnO increased the relative optical density of ZIP8 (mainly expressed in cells of brush border) and MT2A (mainly expressed in villus lamina propria and gland/crypt) (P<0.05). In conclusion, long-term dietary Nano-ZnO showed no obvious side effects on the development of the major organs, liver function, and metabolism of Cu, Fe, and Mn in IUGR pigs, while it increased the Zn absorption and deposition via enhancing the expression of transporters (MT, ZIP, and ZnT families) in the jejunum, rather than via endocytosis as the form of intact nanoparticles.

Simultaneous determination of arsenic, cadmium and lead in plant foods by ICP-MS combined with automated focused infrared ashing and cold trap

A fully automated focused infrared lightwave ashing sample preparation system was proposed and applied to the pretreatment of volatile arsenic, cadmium and lead in plant foods prior to inductively coupled plasma mass spectrometry (ICP-MS) determination. All the steps of ashing pretreatment were automatically accomplished within forty minutes. Gold-plated infrared quartz tubes produced focused infrared to supply a rapid heating. Ozone was used to accelerate sample carbonization. A cool trap was used to capture volatile arsenic, cadmium and lead. Three certified plant food reference materials were determined. The recoveries of the three elements were between 90% and 107%. Five real plant foods were analyzed by the proposed method and microwave digestion. The results showed no significant difference.

Determination of As(III) and As(V) species in some natural water and food samples by solid-phase extraction on Streptococcus pyogenes immobilized on Sepabeads SP 70 and hydride generation atomic absorption spectrometry

The speciation of arsenic(III) and arsenic(V) by using Streptococcus pyogenes immobilized on Sepabeads SP 70 resin has been investigated with solid-phase extraction method. The arsenic levels were determined hydride generation atomic absorption spectrometry (HGAAS) in sample solutions. The procedure presented based on quantitative recoveries of As(III) as >95%. Also the As(V) recoveries were obtained as <5% using the presented method. After reduction of As(V) by using KI and ascorbic acid and waiting 1h later, the system was applied to determination of total arsenic. As(V) was found as the difference between the total As and As(III) content. Various experimental parameters such as pH, amount of microorganism, sample volume, etc. were investigated. The capacity of biosorbent for arsenic(III) was calculated as 7.3 mg/g. The preconcentration factor was found as 36. The relative standard deviation was calculated below 8%. Limit of detection was calculated as 13 ng/L. The validation of the presented procedure was tested by analysis of standard reference materials (NIST SRM 1568a Rice floor and GBW 07605 Tea) and obtained fairly compatible results. The procedure was also successfully applied to arsenic speciation and determination of some natural water and food samples.