Metals biology

Direct uptake by plants and microorganisms. Microbial removal of metals Biological Metals... 

However, the hypersensitive transitions of some lanthanides may be used with some success in probing the metal-biological molecules interactions as pointed out in Chapter 8. Nd3+ is particularly suited for such studies with spectral lines in the region 500-600 nm... 

Although the focus of this section has primarily been on iron and copper complexes, probably the most important transition metals biologically studied by the MCD technique, variable temperature and field dependence studies have also been carried out for complexes of other transition metals such as cobalt and manganese and the techniques described for iron and copper can easily be applied to other metals based on the nature of the ground state. MCD spectroscopy has the key advantage, over other techniques used to study bulk magnetic properties of an entire sample, that spectral bands associated with specific mefal cenfers can be sfudied in isolation. 

RMs for chemical composition (steels, alloys, gases in metals, biological materials of plant and animal origin, geological materials, ores, materials for clinical analysis, glasses, ceramics, etc.)... 

Use Red dye for paper, also for wool and silk where brilliant fluorescent effects are desired and light-fastness is of secondary importance analytical reagent for certain heavy metals, biological stain. 

Toxic metal compounds ° Heavy metals ° Biological waste... 

Brookes, P.C. (1994), The use of microbial parameters in monitoring soil pollution by heavy metals . Biology and Fertility of Soils, Vol. 19, pp. 269-279. 

A complex set of interrelationships involving physical, chemical, biological, and pharmacological factors are involved when a metal ion interacts with a biological system. Therefore, it is more important to characterize the metal-biological system than to characterize the species in a simple chemical system. In a comprehensive work. Walker et al. (2003) reviewed approximately 100 diverse contributions dating from 1835 to 2003 to evaluate the relationships between about 20 physicochemical properties of cations and their potential to produce toxic effects in different organisms. 

The question whether Cr(III) might be toxic is complicated by the fact that it is considered an essential metal. Biologically active Cr(III) facilitates the action of insulin. Chromium deficiency results in impaired glucose tolerance, which can be corrected by the administration of chromium (Anderson et al. 1983 Anderson 1986). Hypoglycemia and its associated symptoms can also be corrected by administration of chromium (Anderson et al. 1987). These effects of chromium supplementation are often associated with improvements in lipid levels, with a net decrease in total lipids and cholesterol and an increase in the ratio of HDL cholesterol to LDL cholesterol (Riales and Albrink 1981 Mossop 1983 Evans 1989 Wang et al. 1989). 

---