Sediment fluorescence analysis

Cassman and King have reported cooperative binding of NADH to beef heart s-MDH (67). They also found evidence for the existence of s-MDH monomer from sedimentation equilibrium analysis at low protein concentrations (67). The fluorescence studies of the binding of NADH to beef heart s-MDH were interpreted in terms of a model in which both monomer and dimer bind NADH with cooperative binding to the dimer (67). The dissociation constant for the first site was about 25 /Jkf and for the second site about 0.18 iiM. 

Within 2 h of addition of concanavalin A (Con A) to mouse splenic lymphocytes, there was repair of 3200 strand breaks per diploid genome (Table 1) DNA strand breaks were assayed by means of fluorescence analysis of DNA unwinding [7]. This technique was used to demonstrate the same phenomenon in pig peripheral blood lymphocytes within 5 h (Table 1). This technique does not differentiate between alkali labile bonds and frank breaks however, this argument does not apply to the work of Johnstone and Williams [3] who used the method of nucleoid sedimentation in neutral gradients. Thus in human lymphocytes, at least, frank breaks exist in resting cells. 

Uchiyama [11] applied this method to the determination of fluorescent whitening agents and alkyl benzenesulphonates and also methylene blue active substances in bottom sediment samples taken in a lake. The muds were filtered off with a suction filter and frozen until analyzed. About 20g of wet bottom mud was extracted three times with a methanol-benzene (1 1) mixture. After the solvent was evaporated using a water bath, the residue was dissolved in hot water and this solution used for analysis. Table 10.2 shows the analytical results for methylene blue active substances (MBAS), alkyl benzene-sulphonate (ABS), and fluorescent whitening agent (FWA) in bottom sediments. 

For the analysis of AEO sediment extracts on HPLC-fluorescence (FL), it was necessary to derivatise using naphthoil chloride and IV-methylimidazole in order to incorporate a chromophore into the analytes [37]. 

A new suspension array concept based on sedimentation and microscopic imaging was introduced by Moser et al. [98], Magnetic microbeads settle to the bottom of a microplate well by magnetic forces and form randomly ordered arrays, which are examined by fluorescence microscopy and automated imaging analysis. Each bead carries specific capture molecules and can be identified by a defined luminescent code. 

For the determination of organotin compounds (tributyltin, triphenyltin, triethyltin, and tetra-ethyltin) a MAE is proposed before the normal phase (NP) HPLC/UV analysis [35], In organotin and arsenic speciation studies, hydride generation is the most popular derivatization method, combined with atomic absorption and fluorescence spectroscopy or ICP techniques [25,36], Both atmospheric pressure chemical ionization (APCI)-MS and electrospray ionization ESI-MS are employed in the determination of butyltin, phenyltin, triphenyltin, and tributyltin in waters and sediments [37], A micro LC/ESI-ion trap MS method has been recently chosen as the official EPA (Environmental Protection Agency) method (8323) [38] it permits the determination of mono-, di-, and tri- butyltin, and mono-, di-, and tri-phenyltin at concentration levels of a subnanogram per liter and has been successfully applied in the analysis of freshwaters and fish [39], Tributyltin in waters has been also quantified through an automated sensitive SPME LC/ESI-MS method [40],... 

LAB 11 Laboratory for analysis of unfiltered water samples, stream sediment and floodplain sediment samples. Ion chromatography (IC) is used for Cf, Br, N03% N02, P043, S042 and ion specific electrode (ISE) for F and Total Organic Carbon (TOC) in water. X-Ray fluorescence spectrometry (XRF) analyses for over 30 elements is used for stream sediment and floodplain sediment samples. To be nominated (suggestion British Geological Survey). 

Each spectroscopic method has a characteristic application. For example, flame photometry is still applicable to the direct determination of Ca and Sr, and to the determination of Li, Rb, Cs and Ba after preconcentration with ion-exchange resin. Fluorimetry provides better sensitivities for Al, Be, Ga and U, although it suffers from severe interference effects. Emission spectrometry, X-ray fluorescence spectrometry and neutron activation analysis allow multielement analysis of solid samples with pretty good sensitivity and precision, and have commonly been applied to the analysis of marine organisms and sediments. Recently, inductively-coupled plasma (ICP)... 

The major elements of marine sediments are still determined by classical gravimetric and volumetric methods. Atomic absorption spectrometric methods have been applied to sediment analysis, although emission spectrometry, X-ray fluorescence spectrometry and neutron activation analysis... 

X-ray fluorescence spectrometry (XRF) and instrumental neutron activation analysis (INAA) are commonly used for multi-element analysis of rock, soil, and sediment samples since they do not require chemical dissolution. However, the detection limit for arsenic using XRF is on the order of 5 mg kg and is too high for many environmental purposes. Once dissolved, arsenic can be determined using many of the methods described above... 

The 30-mm sediment slices of the segmented cylindrical cores obtained from box coring at the seven stations were dried, pulverized, and thoroughly mixed to yield a uniform sample for analysis. Sediment from each of these slices was analyzed by two independent methods. The first method used a Perkin-Elmer model 5000 atomic absorption spectrophotometer (AA) for the elements Fe, Mn, Ti, Pb, Zn, Cu, Cr, Ni, Co, Hg, and Cd (9). The second method utilized a Philips PW 1410 X-ray fluorescence spectrometer for the analysis of elements Fe, Mn, Ti, Ca, K, P, Si, Al, Mg, Na, Pb, Zn, Cu, Cr, V, and Ba (10). The AA analysis was chosen because of the known accuracy and sensitivity to a wide spectrum of elements. The XRF analysis was chosen for its accuracy and similar nondestructive mode of analysis equivalent to the shipboard XRF analysis. Good agreement between the AA and the XRF values was felt to be imperative because the Philips XRF equipment was to be used in the land-based multielement analysis of the CS -collected sediment samples. 

T. Gasparics, I. Csato, Gy. Zaray, Analysis of Antarctic marine sediment by inductively coupled plasma atomic emission and total reflection X-ray fluorescence spectrometry, Microchem. J., 55 (1997), 56-63. 

Carbonized coal products have a unique fingerprint by both GC and fluorescence analyses. Both these fingerprints confirm that sediments from the Elizabeth River are contaminated with carbonized coal products and allow for the detection of carbonized coal hydrocarbons, even in the presence of petroleum-derived hydrocarbons. Fluorescence allows for the rapid analysis of more samples and shows the contamination within the Elizabeth River to be widespread. Carbonized coal products in the sediments may constitute a chronic long-term source of PNA s to the water column. 

Panhli, F., Manceau, A., Sarret, G., Spadini, L., Bert, V., Kirpichtchikova, T., Matthew, M., and Ahamdach, N. (2005). Evolution of Zn speciation induced by phytostabilization in a contaminated sediment, using scanning electron microscopy, x-ray fluorescence, EXAFS spectroscopy, and principal component analysis. Geochim. Cosmochim. Acta 69, 2265-2284. 

Figure 7.13. HPLC analysis of polynuclear aromatic hydrocarbons (PAHs) in a marine sediment (NIST SRM 1941) using programmed fluorescence detection. Reprinted with permission...

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