Tissue analysis biological tissues

Sampling of biological tissue is done by removing the entire organ, which is then homogenized before smaller portions are taken for analysis. Alternatively, several small portions of tissue may be combined to form a composite sample. The composite sample is then homogenized and analyzed. 

Mineral elements in biological tissue sections, derivation and use of equation for determination, 301-305 Minerals, analysis, use of borax flux by Claisse in, 173, 207, 209 use of curved-crystal spectrograph for small samples in, 206, 207 assay by x-ray emission spectrography, 199-209... 

Tin plate, thickness of tin coating on, determination by x-ray spectrography, 148, 149, 157, 158 Tissues, determination of dry weight by absorptiometry, 297-300 Tissue sections, biological, determination of mineral elements in, 301-305 Titanium, as internal standard in vanadium determination, 188 determination by x-ray emission spectrography, 222, 329 trace analysis by x-ray emission spectrography, 163, 225-229 Topaz, as analyzing crystal, 116-118, 220, 318-327 Total reflection, 112, 117... 

The primary method for detecting methyl parathion and metabolites in biological tissues is gas chromatography (GC) coupled with electron capture (BCD), flame photometric (FPD), or flame ionization detection (FID). Sample preparation for methyl parathion analysis routinely involves extraction with an organic solvent (e g., acetone or benzene), centrifugation, concentration, and re suspension in a suitable solvent prior to GC analysis. For low concentrations of methyl parathion, further cleanup procedures, such as column chromatography on silica gel or Florisil are required. 

MS imaging is extensively used for biological applications, in analysis of tissues and small organisms, but its applications are in principle unlimited. Hence, it should be possible for applications in cultural heritage to become available soon. 

Knowledge of complex permittivities of appropriate electrolyte solutions is useful in assessing interactions of microwave radiation with biological tissues. A full study and analysis of complex permittivities of sodium chloride solutions as a function of concentration, temperature, and microwave frequency (207) has laid the foundations for a similar investigation of calcium salt solutions. 

Techniques for analysis of different mercury species in biological samples and abiotic materials include atomic absorption, cold vapor atomic fluorescence spectrometry, gas-liquid chromatography with electron capture detection, and inductively coupled plasma mass spectrometry (Lansens etal. 1991 Schintu etal. 1992 Porcella etal. 1995). Methylmercury concentrations in marine biological tissues are detected at concentrations as low as 10 pg Hg/kg tissue using graphite furnace sample preparation techniques and atomic absorption spectrometry (Schintu et al. 1992). 

The potential for the employment of plasma emission spectrometry is enormous and it is finding use in almost every field where trace element analysis is carried out. Some seventy elements, including most metals and some non-metals, such as phosphorus and carbon, may be determined individually or in parallel. As many as thirty or more elements may be determined on the same sample. Table 8.4 is illustrative of elements which may be analysed and compares detection limits for plasma emission with those for ICP-MS and atomic absorption. Rocks, soils, waters and biological tissue are typical of samples to which the method may be applied. In geochemistry, and in quality control of potable waters and pollution studies in general, the multi-element capability and wide (105) dynamic range of the method are of great value. Plasma emission spectrometry is well established as a routine method of analysis in these areas. 

C. N. McEwen, R. G. McKay, and B. S. Larsen. Analysis of Solids, Liquids, and Biological Tissues Using Solids Probe Introduction at Atmospheric Pressure on Commercial LC/MS Instruments. Anal. Chem., 77(2005) 7826-7831. 

The analysis of human plasma for acetaminophen, the active ingredient in some pain relievers, involves a unique extraction procedure. Small-volume samples (approximately 200 fiL) of heparinized plasma, which is plasma that is treated with heparin, a natural anticoagulant found in biological tissue, are first placed in centrifuge tubes and treated with 1 N HC1 to adjust the pH. Ethyl acetate is then added to extract the acetaminophen from the samples. The tubes are vortexed, and after allowed to separate, the ethyl acetate layer containing the analyte is decanted. The resulting solutions are evaporated to dryness and then reconstituted with an 18% methanol solution, which is the final sample preparation step before HPLC analysis. The procedure is a challenge because the initial sample size is so small. 

Very few data are available for concentrations of non-ionic surfactants in biota. This is partly due to difficulties encountered in the analysis of these compounds in biological tissues [31]. The data reported in the literature for APEOs are shown in Table 6.4.3. 

A selected list of reference materials (sediments as well as biological tissues) distributed by several Canadian, U.S., and E.U. sources shows a wide range of solid samples that could be used for comparative analysis of major organic elements (Table 4.2). These materials are widely available and have been analyzed for at least some constituents. In addition, these materials are homogeneous and can be expected to exhibit stable compositions over time. All of the thirty or so listed reference materials,... 

Neilen et al. [502] coupled an SFE system with a GC-ECD for on-line determination of PCBs which had been trapped onto solid adsorbents such as Tenax. Their application was primarily to determine organic compounds in the atmosphere, but such a system could be adapted to trap a cleaned-up extract from biological tissue prior to analysis by GC-ECD or MS. 

Watson DC, Midgeley JM, Chen RN, Fluang W, Bain CM, et al. 1990. Analysis ofbiogenic amines and their metabolites in biological tissues and fluids by gas-chromatographynegative ion chemical ionization mass spectrometry (GC-NICIMS). J Pharm Biomed Anal 8 899. 

Because MALDI is a desorption technique, it is particularly suited for the analysis of surfaces such as biological tissues [50]. In this application, the matrix is applied on the complete surface of the tissue. The laser resolution is about 100 pm and complete analyte distribution images (low molecular weight compounds, peptides, proteins) can be recorded [51, 52]. 

Stab, J.A., Udo, A., Brinkman, Th., Cofino, W.P. (1994). Validation of the analysis of organotin compounds in biological tissues using alkylation and gas chromatography. Applied Organometallic Chemistry, 8, 577 — 585. 

Electrothermal atomization is particularly useful when the amount of sample is very small, when very low levels of detection are required and when the matrix is dilute or volatile. These criteria often apply to clinical samples (a pin-prick sample of blood produces only 50-100 mm of whole blood, but this is sufficient for analysis using an electrothermal atomizer, hence it is not essential for an intravenous sample to be taken). For such samples, often pretreatment is not required, and body fluids and biological tissues can be ashed in situ in the furnace. This also applies to some foods, although others may need some preliminary wet ashing. 

II. Fukushima T, Nixon JC (1980) Analysis of reduced forms of biopterin in biological tissues and fluids. Anal Biochem 102 176-188... 

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