A multichannel atomic absorption instrument: simultaneous analysis of zinc, copper, and cadmium in biologic materials

Measurement of copper in biological samples by flame or electrothermal atomic absorption spectrometry

Guidelines presented here allow for copper analysis of biological materials by methods that are very sensitive, that require little sample preparation, that have few chemical or spectral interferences, that are inexpensive, and that require only usual care in contamination control. The commercial instruments for FAAS and ETAAS from Perkin-Elmer, from Varian, and from Instrumentation Laboratories Inc. (Allied Analytical Systems) all work well in either the flame or the flameless mode. Background correction techniques are not essential for copper analysis if care is taken with the sample preparation to minimize the background signals. Different types of burners will work adequately if one makes certain that the viscosity of the sample and the control products are similar to the calibration standards. Further, dilution of samples is preferred over increasing the viscosity of the calibration standards by the addition of a protein containing solution or a substance such as glycerol. A 1:10 dilution of blood plasma or serum with dilute nitric acid or water is all that is necessary for copper analysis by the FFAS methods. Cation and anion effects should be tested by bracketing the concentrations of the ions found in the sample with known amounts of ions in the sample solutions. Increasing the concentrations of the ions thought to interfere while keeping the copper concentration constant is another way to test for ion interferences.(ABSTRACT TRUNCATED AT 250 WORDS)

Trace elements in human body fluids and tissues

Published figures for trace element concentrations in body fluids and tissues of apparently healthy subjects are widely divergent. For a considerable time, the apparent disparities were readily ascribed to biological sources of variation such as age, sex, dietary habits, physiological conditions, environmental exposure, geographical circumstances, or similar influences. Growing evidence, however, suggests that this interpretation may be seriously questioned in numerous instances. First, values obtained in reference materials leave no doubt that some previous studies must have been subject to gross analytical inaccuracies. Second, it has now been thoroughly documented that inadequate sample collection and manipulation may drastically distort the intrinsic trace element content of biological matrices. This review scrutinizes data reported by a number of investigators. In an effort to settle the currently flourishing confusion, critically selected reference values are set forth for trace element levels in human blood plasma or serum, packed blood cells, urine, lung, liver, kidney, and skeletal muscle tissue.

Zinc-dependent chemotactic defect in an infant with acrodermatitis

A 5-month-old infant developed acrodermatitis enteropathica when weaned from breast milk to cows' milk. Plasma zinc concentration was low. T- and B-lymphocyte functions were normal, but there was a severe defect of neutrophil chemotaxis. Oral treatment with zinc sulphate (40 mg daily) induced an immediate clinical improvement, with restoration of normal plasma zinc level and complete correction of neutrophil chemotaxis.

Effects of cadmium on the immune system of mice

Chronic oral exposure of mice to Cd++ inhibits cell-mediated immunity of delayed type hypersensitivity induced by sheep red blood cells (SRBC). No effect was detected on humoral immune response to SRBC. Spleen cells derived from mice exposed to Cd++ showed in vitro enhanced response to T and B cell mitogens. These results demonstrate that Cd++ exposure alters the immune system of mice.

Effect of acute disease and ACTH on serum zinc proteins

The effect of acute disease and ACTH infusion on serum zinc proteins was studied in serums from 156 healthy and diseased subjects. The mean (+/-2 S.D.) zinc content of 20 normal serums was 96 +/- 20 microng per 100 ml. In 87 serums from acutely ill patients the zinc ranged from 92 to 40 microng per 100 ml. The mean values for nearly all categories of disease studied were lower than normal (P is less than 0.001). Chromatography of normal serum on Sephadex G-100 separates two protein fractions, I and II, containing 37.8+/-8.8 and 76+/-10 microng of zinc per 100 ml, respectively. In serum from diseased patients the zinc in fraction I is unaltered whereas that in fraction II decreases to 29.8+/-7.5 microng per 100 ml (P is less than 0.001). ACTH administration reduces secrum zinc from 10 to 60 microng per 100 ml, the decrements being due to changes in the zinc content of fraction II. Thus, ACTH may have an important role in the reduction of zinc content associated with pathologic states.