Selectivity of analysis

Multiresidue determination of QUIN antibiotics using liquid chromatography coupled to ACPI-MS and MS/MS was also described (197). In the source, collision-induced dissociation was used to optimize fragmentation to produce mass spectra consisting of the protonated molecule and two characteristic fragment ions of nearly equal intensity. Selected ion monitoring of three ions per QUIN yielded a sensitive detection in catfish muscle extracts (detection limits of 0.8-1.7 yug/kg). An MS/MS was used to increase the specificity and selectivity of analysis. The preseparation step was very simple only the LLE procedure is required. 

Rosenfeld, J.M. 1999. Solid-phase analytical derivatization Enhancement of sensitivity and selectivity of analysis. J. Chromatogr. A 843 19-27. 

ILs can be applied not only to existing methods whose sensitivity and selectivity of analysis should be improved, but their behavior and properties offer new opportunities in chemical analysis. 

Ultraviolet spectrophotometry (UV) at a single wavelength furnishes minimum selectivity of analysis however, with the current accessibility of diode array detectors, it is conceivable to obtain sufficient simultaneous information at various wavelengths to assure greater reliability. 

Problem definition, information gathering and organisation of the work - Selection of analysis rnethod... 

The first parts of the AOP 52 give an overview of the management and steering process and technical methods and techniques within the development program, see chapters 3.1 to 3.6. One emphasis lies on an extensive selection of analysis methods for hardware and software. 

UV/visible/NlR semiconductor diode lasers (DLs) as sources of tunable narrowband resonance radiation have been discussed in Section 22.2.2. The practical and technical advantages of visible/ NIR DLs are ease of operation, small size, room-temperature operation, and low price. In comparison with hollow cathode lamps (HCLs), they have such advantages as high spectral power, spatial coherence, and tunability. Owing to these features, detection limits, dynamic range, and selectivity of analysis are all significantly improved. 

In its general form, the basic framework accordingly shall include analysis of cause frequency and consequence, justification of control measure, and final evaluation, as shown in Fig. 11/4.1.5-1. The entire procedure is greatly influenced by a number of factors such as people, viewing the system, appropriate selection of analysis process control measure, updating, and maintenance as shown. The operator s safety philosophy plays vital role in modifying the stmcture of risk analysis. If the intent is to... 

It is also recommended that this pattern be repeated around the circuitry in four places around the corners to enable the most flexible selection of analysis algorithms as described in the discussion of analysis later in this section. 

In this paper we have proposed definitions for the three main methods of gas adsorption in an attempt to clarify the confusion evident from published literature. We have also shown that, for microporous analysis, careful selection of analysis conditions is necessary to achieve meaningful results. Using commercially available instrumentation, we have demonstrated uniquely detailed isotherms of zeolite materials using both argon and water as probe molecules. Commercial instruments that can measure and record a large number of data points at very low relative pressure will play an important role in the future development of gas adsorption characterisation. 

Tandem MS monitoring selected fragment ions produced in the collision cell of a sector or multiquadrupole instrument or in an ion-trap chamber offers advantages over single-stage MS in terms of selectivity of analysis and specificity in molecular structure determination [104]. Tandem MS techniques have been widely used with good results for the analysis of polyhalogenated compounds, such as isomers of the polychlorinated dibenzo-y dioxines and dibenzofurans [105], PCBs [106], PCNs, and related compounds [107]. However, the applica tion of MS-MS to the analysis of PCTs and toxaphene has been very limited. 

---