Rapid analytical methods

If, in the above example, the analytical error was 0.2 per cent then the total error sT would be equal to 3.006 per cent. Hence the contribution of the analytical error to the total error is virtually insignificant. Youden7 has stated that once the analytical uncertainty is reduced to one-third of the sampling uncertainty, further reduction of the former is not necessary. It is most important to realise that if the sampling error is large, then a rapid analytical method with relatively low precision may suffice. 

With the recent Increase In activity at hazardous waste sites where cleanup and remedial action are underway, there has emerged a need for rapid analytical methods for assessing contamination in water, sediment, and soil. Of special Interest, because of widespread use and disposal. Is the group of materials known as PCB s (polychlorinated biphenyls). 

The refractive index is another very rapid analytical method for determining purity and identity of a substance. It is uniquely useful for quality control monitoring of raw materials and finished products. Many students encounter a refractometer first as a universal detector for high-performance liquid chromatography. 

Perry NB, van Klink JW, Burgess EJ and Par-menter GA (1997) Alkamide levels in Echinacea purpurea a rapid analytical method revealing differences among roots, rhizomes, stems, leaves and flowers. Planta Med 63, 58-62. 

Takayama K, Miyata H, Mimura M, et al. 1988. Rapid analytical method for PCDDs, PCDFs, and polychlorobenzenes in samples from municipal waste incinerators. Eisei Kagaku 34 231-236. 

Dwivedi P, Hill HH Jr (2008) A rapid analytical method for hair analysis using ambient pressure ion mobility mass spectrometry with electrospray ionization (ESI-IMMS). Int J Ion Mobil Spec 11 61-69... 

Rapid Analytical Methods. One approach to industrial biomass analysis is to use published,... 

The wet chemical and rapid analytical methods described above are being used on a daily basis in the U.S. Department of Energy s Office of the Biomass Program. The methods are used primarily to keep track of chemical fractions of plant cell walls... 

NIR data were converted to compositions using the stover 5c rapid analytical method developed at NREL.129 The ability of the stover 5C methods to accurately measure the composition of corn stover feedstock is shown in Fig. 33.17, where the composition, as determined by NIR/PLS, is compared to measurement of the same samples using standard wet chemical methods. 

EPA. 1978a. Development of a rapid analytical method for determining asbestos in water. Report to U.S. Environmental Protection Agency, Office of Research and Development, Health Effects Research Laboratory, Athens, GA, by Battelle Columbus Laboratories. EPA-600/4-78-066. 

Ion chromatography (IC) was developed in the 1970s by Small et al. (1975). It is a powerful technique for the measurement of ionic species, such as fluoride, chloride, nitrite, nitrate, and sulphate and cations like lithium, sodium, ammonium, and potassium. It is very useful for analysis of anions for which there are no other rapid analytical methods, and it is also commonly used for organic species such as amino acids, amines, and proteins. The most commonly used detection method is conductivity,... 

When screening for drug permeability in early discovery, processing the large amount of samples requires sensitive, simple and rapid analytical methods. In order to reduce the analytical workload so that no bottleneck is created, different options have been proposed, including the use of radiolabelled compounds (if they are available) or the implementation of generic LC-MS methods. The use of different additives to the media to overcome previously mentioned limitations, should not compromise the analytical method and should not require additional manipulations for sample preparation. Therefore, efforts have been made to propose and use additives that are compatible with the analytical method (discussed in section Proteins or Micellar Excipients for Sink Conditions ). The use of analysis-friendly additives can result in a significant reduction of cycle time,... 

Zhao, Y Chow, D.T. Thomas, S. Yin, L. Semin, D. Rapid Analytical Method Development in Support of Medicinal Chemistry Using Parallel and Multidimensional Separation Techniques, in Proceedings of the HPLC2003 Symposium, Nice, France, June 15-19, 2003, p. 149. 

The reaction progress must be very slow relative to the time required for aliquot removal and time of sample analysis, or in the latter case a rapid quench can be carried out. A rapid analytical method is UV/visible spectrophotometry. 

Ion Chromatography (IC) is a subset of one of the modes of HPLC - ion-exchange chromatography. It uses ion-exchange resins to separate ions based on their interaction with the fixed groups on the resin. Its greatest use is for the analysis of anions for which there are no other rapid analytical methods. It is also commonly used for cations and simple biochemical species such as amino acids. Aqueous solutions are normally required for analysis. 

Methods based on derivatization and GC analysis have been developed (Hoshika and Muto, 1978) but are of low popularity. A rapid analytical method for aldehydes is based on sampling on a solid adsorbent followed by thermal desorption and GC/FID detection. The required collection time is < I h per sample and no further sample preparation steps are needed. Uhde and Borgschulte (1999) have tested several combinations of adsorbents for sampling aldehydes from acetic aldehyde up to decanal. Tenax TA was found to be suitable for retaining the aliphatic aldehydes from butanal to decanal without breakthrough. Figure 1.2-3 shows the results of a static experiment in a 1-m- stainless steel... 

An EPA-approved procedure for the analysis of plutonium in water is listed in Table 6-2. In addition, the following ASTM standard methods relate to the measurement of plutonium in water D 3648, D 3084, D 3972, and D 1943 (ASTM 1981, 1982a, 1982b, 1987). Recent work has focused on more rapid analytical methods in order to determine monitor plutonium levels in waste process streams at nuclear facilities. For example, Edelson et al. (1986) have investigated the applications of inductively-coupled plasma-atomic emission spectrometry (ICP-EAS) to routinely analyze water samples. 

RockEval (also Rock-Eval, RockEval analysis) A rapid analytical method that utilizes pyrolysis to provide a semi-quantitative measure of the relative proportions of hydrogen, carbon and oxygen in bulk sedimentary organic matter. The instrument heats sediment samples to measure the amounts of hydrocarbons and hydrocarbon-like substances that escape at different temperatures from the organic matter contained in the sediment. The unit also calculates the amount of CO2 created during thermal decomposition of the organic matter. The results of Rock-Eval pyrolysis can help to identify the biotic sources of sediment organic matter. 

Witten ML, Bowers MC, Hall JN, Quan SF, Shen Q, Lemen RJ. A rapid analytical method for measuring drug distribution in aerosols. Radiopharmacy 1992 20 155-158. 

The polymer industry has long been in search of a simple, rapid analytical method to measure stabilizer content in pigment/additive concentrates. This feasibility study was undertaken to examine the accuracy, scope and limitations of the NIR technique when applied to the measurement of traditional light stabilizers in color concentrates. 

Anions have also been determined using conventional IMS with an FSI ion source and included arsenate, phosphate, sulfate, nitrate, nitrite, chloride, formate, and acetate. Distinct peak patterns and reduced mobility constants were observed for respective anions. Application to authentic water samples for the determination of nitrate and nitrite demonstrated the feasibility of using FSI-IMS as a rapid analytical method for monitoring nitrate and nitrite in water systems. The method was used for on-site measurement by exchanging air for nitrogen as the drift gas without complications. The linear dynamic range was 1,000, and detection limits were 10 ppb for nitrate and 40 ppb for nitrite. 

Dwivedi, P. Matz, L.M. Atkinson, D.A. Hill, H.H, Jr., Electrospray ionization ion mobility spectrometry a rapid analytical method for aqueous nitrate and nitrite analysis. Analyst 2004,129,139-144. 

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