Development and characterization of a portable total reflection X-ray fluorescence system using a waveguide for trace elements analysis.

This paper presents a portable total reflection X-ray fluorescence system composed of a 15 W X-ray tube, with a gold anode, a waveguide constituted by two Perspex(®) parallel plates, a Si PIN detector and a quartz optical flat. The critical angle of the total reflection system was experimentally determined by measuring a zinc solution (100 mg/L). The accuracy of the system was checked using SRM 1577b Bovine Liver by NIST as standard reference material. We obtained the absolute detection limits of the following elements: P (450 ± 40 ng), S (200 ± 31 ng), K (30 ± 2.5 ng), Ca (19 ± 3.5 ng), Mn (4.1 ± 0.5 ng), Fe (3.6 ± 0.9 ng), Cu (3.3 ± 0.4 ng) and Zn (3.5 ± 0.3 ng). This paper shows that it is possible to produce total reflection X-ray fluorescence with very compact, efficient, low-cost and easy-to-handle instrumentation using a low-power X-ray tube and a Si PIN compact detector.

Ethanol intake during lactation alters milk nutrient composition and growth and mineral status of rat pups.

Lactating Wistar rats were fed a liquid diet containing either ethanol [ethanol-fed group (EFG)] or an isocaloric amount of carbohydrate [pair-fed group (PFG)] from day 1 postpartum up to day 14 of lactation, to investigate micro/macronutrient milk composition and the mineral status of pups. EFG presented a reduction of daily milk production and milk composition was significantly higher in protein and lower in carbohydrate, while the lipid content was similar to that of PFG. When compared to PFG, the milk of EFG had a decreased proportion of C22:6 n-3 fatty acid and an increase in medium-chain fatty acids and of several minerals. Pups of EFG showed reduced growth and a lower concentration of Cu and Sr in plasma and lower concentrations of Ca, P and Cl, and higher concentrations of Cd in the brain. We conclude that maternal EtOH intake greatly impairs lactational performance and modifies the mineral status of pups.

Ethanol Intake during Lactation Alters Milk Nutrient Composition and Growth and Mineral Status of Rat Pups

Lactating Wistar rats were fed a liquid diet containing either ethanol [ethanol-fed group (EFG)] or an isocaloric amount of carbohydrate [pair-fed group (PFG)] from day 1 postpartum up to day 14 of lactation, to investigate micro/macronutrient milk composition and the mineral status of pups. EFG presented a reduction of daily milk production and milk composition was significantly higher in protein and lower in carbohydrate, while the lipid content was similar to that of PFG. When compared to PFG, the milk of EFG had a decreased proportion of C22:6 n-3 fatty acid and an increase in medium-chain fatty acids and of several minerals. Pups of EFG showed reduced growth and a lower concentration of Cu and Sr in plasma and lower concentrations of Ca, P and Cl, and higher concentrations of Cd in the brain. We conclude that maternal EtOH intake greatly impairs lactational performance and modifies the mineral status of pups.

Characterization of hypoglycemiant plants by total reflection X-ray fluorescence spectrometry.

In this work, synchrotron radiation total reflection X-ray fluorescence spectrometry (SRTXRF) was used to determine trace elements in eight hypoglycemiant plants (Trigonella foenum graecum, Panax ginseng, Pfaffia paniculata, Myrcia speciosa, Zea mays, Harpagophytum procumbens, Syzygium jambolona, and Bauhinia forficate). The elements P, K, Ca, Ti, Mn, Fe, Cu, Zn, Rb, and Sr were detected in all medicinal plants investigated, whereas Si, S, Sc, V, Cr, Co, Ni, Se, Nb, Mo, Sn, Sb, Ba, Hg, and Pb were detected only in some of the samples. The concentration of elements in hypoglycemiant plants varied from 0.15 microg/g of Co to 3.0 x 10(4) microg/g of K and the mean of experimental limit of detection for these elements were 0.14 and 3.6 microg/g, respectively.

Characterization of iron, copper and zinc levels in the colostrum of mothers of term and pre-term infants before and after pasteurization.

Pasteurization is a thermal treatment applied to the milk used in human milk banks so as to provoke the thermic inactivation of pathogenic micro-organisms, with the aim of avoiding contamination of milk that will be offered to new-born infants in clinical conditions very often demanding special care. The literature has very little data available relating to the effect of pasteurization on the concentration of oligo-elements in human milk. The objective of this study was to evaluate the effect of pasteurization on the concentrations of iron (Fe), copper (Cu) and zinc (Zn) in the colostrum of mothers of pre-term (PT) and term (T) infants. Samples were collected from the day of birth to the seventh day after birth. The oligo-elements were analyzed using the total reflection X-ray fluorescence technique with synchrotron radiation. The following results of Fe, Cu and Zn (means +/- SD) were obtained for the PT and T colostrum samples, non-pasteurized and pasteurized, respectively: PT: 1.96 +/- 0.73 mg/l Fe/Zn/5.39 +/- 2.73 mg/l Zn; T: 1.71 +/- 1.01 mg/l Fe/1.46 +/- 0.99 mg/l Fe, 0.54 +/- 0.29 mg/l Cu/0.49 +/- 0.19 mg/l Cu, 6.97 +/- 2.82 mg/l Zn/6.75 +/- 2.62 mg/l Zn. There was a significant reduction in the levels of Fe, Cu and Zn in the samples of pasteurized colostrum. These results suggest that, despite the observance of a diminution in the levels of Fe, Cu and Zn in the samples of pasteurized colostrum, the values fell within the acceptable range for the specific nutritional needs of new-born infants during this period of lactation.