Imaging and quantification of trace metals in thin biological specimens using microprobe techniques: Synchrotron induced X-ray fluorescence microprobe and nuclear microprobe

XRF and PIXE Analysis of light and Dark Adapted Ocular Tissue

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100053619 ◽

1982 ◽

Vol 40 ◽

pp. 190-191

Author(s):

B. J. Panessa ◽

H. W. Kraner ◽

J. B. Warren ◽

K. W. Jones

Keyword(s):

Trace Metals ◽

Pigment Epithelium ◽

Nerve Impulse ◽

Light Response ◽

Ocular Tissue ◽

Emission Spectrometry ◽

Retinol Dehydrogenase ◽

Pixe Analysis ◽

X Ray ◽

Optimal Function

During photoexcitation the retina requires specific electrolytes and trace metals for optimal function (Na, Mg, Cl, K, Ca, S, P, Cu and Zn). According to Hagins (1981), photoexcitation and generation of a nerve impulse involves the movement of Ca from the rhodopsin-ladened membranes of the rod outer segment (ROS) to the plasmalemma, which in turn decreases the in-flow of Na into the photoreceptor, resulting in hyperpolarization. In toad isolated retinas, the presence of Ba has been found to increase the amplitude and prolong the delay of the light response (Brown and Flaming, 1978). Trace metals such as Cu, Zn and Se are essential for the activity of the metalloenzymes of the retina and retina pigment epithelium (RPE) (i.e. carbonic anhydrase, retinol dehydrogenase, tyrosinase, glutathione peroxidase, superoxide dismutase...). Therefore the content and fluctuations of these elements in the retina and choroid are of fundamental importance for the maintenance of vision. This paper presents elemental data from light and dark adapted frog ocular tissues examined by electron beam induced x-ray microanalysis, x-ray fluorescence spectrometry (XRF) and proton induced x-ray emission spectrometry (PIXE).

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Quantification and localization of trace metals in natural plankton cells using a synchrotron X-ray fluorescence microprobe

Journal de Physique IV (Proceedings) ◽

10.1051/jp4:20030117 ◽

2003 ◽

Vol 104 ◽

pp. 435-438 ◽

Cited By ~ 3

Author(s):

B. S. Twining ◽

S. B. Baines ◽

N. S. Fisher ◽

C. Jacobsen ◽

J. Maser

Keyword(s):

Trace Metals ◽

X Ray

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Trace Metals in Microcrustaceans and Brazilian Waterweed from a Contaminated Chilean Wetland Using Total Reflection X-Ray Fluorescence Spectrometry

Microchimica Acta ◽

10.1007/s00604-006-0519-8 ◽

2006 ◽

Vol 154 (3-4) ◽

pp. 261-268 ◽

Cited By ~ 10

Author(s):

Stefan Woelfl ◽

Margarete Mages ◽

Francisco Encina ◽

Francisco Bravo

Keyword(s):

Trace Metals ◽

Total Reflection ◽

Fluorescence Spectrometry ◽

X Ray

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Ferritin Crystals in the Gut Caeca of a Deep-Sea Hydrothermal Vent Stegocephalid (Crustacea: Amphipoda)

Journal of the Marine Biological Association of the United Kingdom ◽

10.1017/s0025315400033968 ◽

1997 ◽

Vol 77 (1) ◽

pp. 269-272 ◽

Cited By ~ 4

Author(s):

P.G. Moore ◽

P.S. Rainbow

Keyword(s):

Trace Metals ◽

Hydrothermal Vent ◽

Tectonic Activity ◽

Amphipod Species ◽

Single Pair ◽

Thin Sections ◽

Widespread Occurrence ◽

X Ray ◽

Mid Atlantic Ridge ◽

High Concentrations

Ferritin crystals and calcium granules are reported from the ventral ceaca of Steleuthera ecoprophycea (Amphipoda: Stegocephalidae) collected from the Snake Pit hydrothermal vent, Mid-Atlantic Ridge (3520 m).In a series of earlier papers (Moore & Rainbow, 1984, 1989, 1992; Moore et al., 1994), the authors described the widespread occurrence of intracellular, octahedral crystals of ferritin in the ventral caeca of a range of stegocephalid amphipod species from the continental shelf epibenthos and oceanic plankton. The discovery at 3500 m of a new Steleuthera species (S. ecoprophycea), from a hydrothermal vent on the Mid-Atlantic Ridge was announced recently by Bellan-Santini & Thurston (1996), and a complete description is provided therein.Oceanic ridge sites are notable for their tectonic activity and the presence of a diversity of trace metals at high concentrations is to be expected in hydrothermal plumes emanating from such regions (German & Angel, 1995). The detoxification of accumulated trace metals in the ventral ceaca of stegocephalid amphipods from uncontaminated environments is now relatively well known (see above), so it was of interest to investigate whether a vent stegocephalid showed an atypical presence of trace metals in detoxified form in cells of the ventral caeca. The results following from an opportunity to investigate this are reported herein.Material was derived from a dive made by the submersible ‘Alvin’ at Snake Pit hydrothermal field, Mid-Atlantic Ridge (23°23′N 44°56′W), 3520 m, on 16 June 1993 (see Bellan-Santini & Thurston, 1996). Steleuthera ecoprophycea was preserved in 70% alcohol. Subsequently to dissection, the single pair of ventral caeca from each of the four damaged amphipods investigated were post-fixed in 4% glutaraldehyde. For electron microscopy and x-ray microanalysis in STEM mode, ventral caecal tissues were then dehydrated through 95% and absolute ethanol, cleared in propylene oxide, embedded in TAAB resin, sectioned at 0·5 μm (semi-thin sections) on a Reichert OmU2 ultramicrotome and examined without staining in a JEOL 100C electron microscope equipped with LINK system EDX energy dispersive x-ray microanalyser.

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X-ray Fluorescence Analysis of Trace Metals in the Annual Growth Layers of Freshwater Mussel Shells

Advances in X-ray Analysis ◽

10.1154/s0376030800020140 ◽

1989 ◽

Vol 33 ◽

pp. 665-670

Author(s):

William E. Maddox ◽

Leon Duobinis-Gray ◽

David A. Owen ◽

James B. Sickel

Keyword(s):

Trace Metals ◽

Metal Pollution ◽

Freshwater Mussels ◽

Freshwater Mussel ◽

Fluorescence Analysis ◽

Annual Growth ◽

X Ray ◽

Filter Feeders ◽

Mussel Shells

Freshwater mussels (Mollusca: Unionidae) are filter feeders that are relatively immobile, widely distributed and are known to concentrate trace metals in their shells (1,2,3). These characteristics make them good candidates for monitoring metal pollution in lakes and rivers. Another characteristic of mussels that make them particularly attractive as pollution monitors is the fact the shell is deposited in distinctive, annual growth layers. The concentrations of metals in these shell layers may provide a history ol the metals present in the environment where the mussel was collected.

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Proshchenkoite-(Y) from Russia — a new mineral species in the vicanite group: descriptive data and crystal structure

Mineralogical Magazine ◽

10.1180/minmag.2008.072.5.1071 ◽

2008 ◽

Vol 72 (5) ◽

pp. 1071-1082 ◽

Cited By ~ 4

Author(s):

G. Raade ◽

J. D. Grice ◽

M. Erambert ◽

P. Kristiansson ◽

T. Witzke

Keyword(s):

Crystal Structure ◽

New Species ◽

Analytical Data ◽

New Mineral ◽

Nuclear Microprobe ◽

Descriptive Data ◽

X Ray ◽

New Mineral Species ◽

Mohs Hardness ◽

A New Species

AbstractA REE-bearing fluorosilicate from the Tommot REE-Nb deposit in Yakutia, Russia, described without a name in 1966, is characterized here as a new species, proshchenkoite-(Y), of the vicanite group of borosilicates. Wavelength-dispersive electron probe analyses gave the following empirical formula: Y3.70REE7.54Ca1.55Na1.16Mn0.77Th0.10Pb0.01)Σ14.83(Fe2+0.83Mn0.15Ti0.02)Σ1.00Ca1.00(P0.70Si0.26As0.04)Σ1.00Si0.26B3.20(O34.55F13.45)Σ48. Boron was analysed with a nuclear microprobe method based on the nuclear reaction 11B(p,α)2α. The simplified formula is (Y,REE,Ca,Mn)15(Fe2+,Mn)Ca(P,Si)Si6B3O34F14. The mineral is trigonal, R3m, with a = 10.7527(7) Å, c = 27.4002(18) Å, V = 2743.6(6) Å 3, Z = 3. The crystal structure was refined to Rl = 0.042 for 1819 observed reflections. Proshchenkoite-(Y) is isostructural with okanoganite-(Y), vicanite-(Ce) and hundholmenite-(Y), and the differences in site occupancies are discussed. The strongest six reflections of the X-ray powder-diffraction pattern [dobs in Å, (I), (hkl)] are: 4.441, (36), (202); 3.144, (77), (214); 3.028, (45). (009); 2.968, (100), (027); 1.782, (32), (330); and 1.713, (32), (1.2.14). The mineral is optically uniaxial (—) with ω 1.734(2) and 8 1.728(2). The Mohs hardness is about 5; density measured on material subject to incipient metamictization is 4.72 g/cm3, as compared to Dcalc = 4.955 g/cm3.The result of electron microprobe analyses of alleged okanoganite-(Y) from the type locality in Okanogan County, Washington, USA, is also presented. We find here also that P > Si at one of the sites, whereas the analytical data of Boiocchi et al. (2004) indicate Si > P. Consequently, the mineral we have analysed is the P analogue of okanoganite-(Y), another new species.

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