Biotic samples

A combination of IPC and inductively coupled plasma (ICP) MS was extensively explored for the speciation of phosphorus, arsenic, selenium, cadmium, mercury, and chromium compounds [108-118] because it provides specific and sensitive element detection. Selenium IPC speciation was joined to atomic fluorescent spectrometry via an interface in which all selenium species were reduced by thiourea before conventional hydride generation [119], Coupling IPC separation of monomethyl and mercuric Hg in biotic samples by formation of their thiourea complexes with cold vapor generation and atomic fluorescence detection was successfully validated [120]. The coupling of IPC with atomic absorption spectrometry was also used for online speciation of Cr(III) and Cr(VI) [121] and arsenic compounds employing hydride generation [122]. 

Shade, C.W. Automated simultaneous analysis of monomethyl and mercuric Hg in biotic samples by Hg-thiourea complex liquid chromatography following acidic thiourea leaching. Environ. Set Technol. 2008, 42, 6604-6610. 

IPC separation of monomethyl and mercuric Hg in biotic samples by formation of their thiourea complexes, coupled to cold vapor generation and atomic fluorescence detection, was successfully validated [18]. The coupling of IPC with atomic absorption spectrometry was also used for online speciation of arsenic compounds employing hydride generation [17]. In the analytical speciation of chromium using in... 

The differences in sampling techniques between liquid and solid and between abiotic and biotic samples need to be clearly determined by the concentration type and level (major, minor, trace and ultratrace for total and speciation analysis) of analytes to be assessed (31). There is a severe contamination risk during collection from sampling tools, means of transport (helicopters, boats, cars, etc.), and handling operations carried out without using any protection (gloves, masks, boots and decontaminated overalls). Consequently, it is important to develop... 

The colleetion and storing of abiotic and biotic samples from different environments (atmospheric, marine and terrestrial eeosystems) was begun systematically during the austral summer in 1994-1995. 

A rather new technique is APPI, which has only been applied in two studies to determine PFOS [57] in river waters and FTOH and sulfonamido derivatives in biotic samples [58]. APPI is a very selective tool and, in stark contrast to ESI, is considered to be virtually imperceptible to matrix effects, which was confirmed in both studies. APCI and especially APPI are not recommended for metabolism studies of unknown compounds, since ionization is very delicate with these methods. Therefore, unknown compounds may not be discovered due to a lack of ionizability. ESI is the method of choice due to the wide range of ionizable compounds after LC separations. 

Chu S, Letcher RJ (2008) Analysis of fluorotelomer alcohols and perfluorinated sulfonamides in biotic samples by liquid chromatography-atmospheric pressure photoionization mass spectrometry. J Chromatogr A 1215 92-99... 

Microwave extraction realized at 120 °C for 30 min with Hexane -Acetone (3 2 V/V) as the extraction solvent was identified as the most effective extraction procedure for isolation of TPH from biotic matrices. The aim of this research is to develop a silica gel and alumina fractionation procedure for plant sample extraction. Column chromatography with two solvents (chloroform and hexane dichloromethane) as a mobile phase were used for clean-up of extract. In this research the efficiency of recovery received from chloroform as a mobile phase. 

Pritchard PH, Gripe CR, Walker WW, et al. 1987. Biotic and abiotic dehydration rates of methyl parathion in freshwater and estuarine water and sediment samples. Chemosphere 16 1509-1520. 

Actinomycetes are typically most abundant in well drained, circumneu-tral to alkaline soils having abundant organic matter. Water-logging and low pH may reduce populations (37, 38). The numbers of actinomy-cetous organisms isolated from the various soil samples in our study follow this pattern. No clear trend emerged as to a particular edaphic or biotic factor causing an increase in the proportion of inhibitory isolates in a soil sample. 

Hydrocarbon-degrading microorganisms are ubiquitous in most ecosystems [32,117] however, it is often very difficult to prove that transformation, degradation, and mineralization actually occur in the environment because it is difficult to distinguish contributions from biotic and abiotic processes under uncontrolled conditions in the natural environment [338]. In contrast, laboratory assays can provide definitive evidence for microbial degradation, and sterilized samples can be used to determine abiotic losses. Thus, contributions from microbial degradation can be differentiated from abiotic loss by a mass balance... 

Three approaches have been recommended to obtain evidence for in situ biodegradation [71,343,344], including (1) quantitative determination of the pollutant of interest in samples collected at different times to show a decrease in its concentration over time, (2) lab oratory-based microbial degradation studies under conditions that mimic the environment to show the potential of biodegradation in the field, and (3) searching for a particular metabolite of biodegradation in samples collected from the field. Thus, without knowing the amount and nature of PAH inputs, it is impossible to estimate any biotic loss of PAHs. 

Capillary gas chromatography allows the analysis of complex mixtures of compounds to be carried out. However, the analysis time per sample is inherently long in order to obtain high resolution of the components, and this limits the throughput of samples. Slurry samples are biotic and therefore subject to continuing changes which are reflected... 

The sampling points must be on groundwater flow lines from the source of contamination or above the observation point. The down-gradient observations must accurately reflect the abiotic and biotic processes occurring between the two points. 

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