High speed quantitation

J. J. Corr, et al., Design considerations for high-speed quantitative mass spectrometry with MALDI ionization, J. Am. Soc. Mass Spectrom. 17, 1129-1141 (2006). 

Recently (Corr 2006) a detailed account of design considerations for, and initial performance characteristics of, a MALDI-MS/MS instrument for high speed quantitative analysis of small molecules has described incorporation of most of the considerations of the preceding paragraph. The use of a triple quadrupole analyzer in MRM mode with a high repetition rate laser avoids the disadvantages associated with use of an o-MALDI-TOF... 

In the identification of different polymorphs in polymers the FTIR technique presents, with respect to the diffraction techniques, the advantage of easier and more rapid measurements. In particular, the high speed of the measurements allows to study the polymorphic behavior under dynamic conditions. As an example let us recall the study of the transition from the a toward the P form of PBT induced by tensile stresses, evaluated by quantitative analysis of the infrared spectra [83],... 

Friedrich Helfferich and Gerhard Klein Quantitative Analysis by Gas Chromatography, Josef Novak High-Speed Liquid Chromatography, Peter M. Rajcsanyi and Elisabeth Rajcsanyi... 

General texts on GC are numerous [118,119] narrow-bore GC was addressed by van Es [120]. Sample introduction techniques and GC inlet systems have been reviewed [25,90] and split/splitless [121] and on-column injection [122] were considered specifically. Stationary phases [123], multiple detection [103], derivatisation [124,125], and quantitative analysis in GC [109] have been described. High-speed GC has recently been reviewed [126]. For a compendium of GC terms and techniques, see Hinshaw [127]. 

Dry column chromatography [528] provides several improvements over traditional column chromatography, such as better resolution and high speed. Another important characteristic is the near-quantitative applicability of TLC results in dry column analysis. Knowledge of the TLC characteristics of a sample is useful before column chromatography is employed. Careful control of the moisture content of the adsorbent is crucial to the dry column as well as other types of chromatography. 

Bullen A, Saggau P (1999) High-speed, random-access fluorescence microscopy II. Fast quantitative measurement with voltage-sensitive dyes. Biophys J 76 2272-2287... 

Successful methods entail precipitation of the amylose from solution as an insoluble complex, which is removed by high-speed centrifuging the amylopectin is isolated from the supernatant liquor by precipitation with alcohol or, more satisfactorily, by freeze-drying. (Precipitation with alcohol does not always appear to be quantitative, and the physical form of the product obtained by freeze-drying is more satisfactory for subsequent dissolution and esterification.) The amylose can then be further purified by reprecipitation with the same or, preferably, a different complexing agent. 

A detector plays an important part in achieving overall performance when optimizing for very short run times with reasonable peak capacities. The detector should match the optimized LC conditions in terms of flow rate and dispersion. The electronics must accurately capture the peak form produced by the column this is most important for quantitative analyses. The data quality may be limited by the laws of physics at high speed. The amount of data produced over time can become an issue. 

The substantial effect of secondary breakup of droplets on the final droplet size distributions in sprays has been reported by many researchers, particularly for overheated hydrocarbon fuel sprays. 557 A quantitative analysis of the secondary breakup process must deal with the aerodynamic effects caused by the flow around each individual, moving droplet, introducing additional difficulty in theoretical treatment. Aslanov and Shamshev 557 presented an elementary mathematical model of this highly transient phenomenon, formulated on the basis of the theory of hydrodynamic instability on the droplet-gas interface. The model and approach may be used to make estimations of the range of droplet sizes and to calculate droplet breakup in high-speed flows behind shock waves, characteristic of detonation spray processes. 

T. (2006) A new strategy of high-speed screening and quantitative structure-activity relationship analysis to evaluate human ATP-binding cassette transporter ABCG2-drug interactions. Journal of Pharmacology... 

Tea (Camellia sinensis) is one of the most frequently consumed beverages in the world and, consequently, an important agricultural product [168], It has been proved many times that tea may reduce cholesterol level, hypertension, and shows antioxidant and anti-microbial effects [169], Because of its importance, a considerable number of analytical methods have been developed for the separation and quantitative determination of the constituents of tea [170,171]. Thus, the application of high-speed counter-current chromatography [172,173], and HPLC-APCI-MS [174] have been reported. 

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