Screening methods colorimetric

Foods Screening Method (FA Salmonella Poly) Colorimetric Monoclonal Clinical Sciences Inc. Organon Teknika Corporation 986.35 18... 

Enzyme IA Screening Method (Bio-Enza Bead Screen) Colorimetric Polyclonal Bioenterprises Pty Ltd. 989.14 118... 

Enzyme IA Screening Method (Q-TROL) Colorimetric Monoclonal Organon Teknika Corp. 993.09 120... 

As part of SW-846, the EPA has validated and approved many immunoassay and colorimetric screening methods for a wide range of contaminants, such as petroleum fuels, pesticides, herbicides, PCBs, and explosives. Immunoassay technology uses the property of antibodies to bind to specific classes of environmental pollutants allowing fast and sensitive semiquantitative or qualitative detection. Colorimetric kits are based on the use of chemical reactions that indicate the presence of target analytes by a change in color. Table 3.9 presents a summary of EPA-approved screening methods and their detection capabilities. 

In addition to test kits used in EPA-approved screening methods, a variety of other test kits are available from several manufacturers, for example, immunoassay test kits for BTEX in soil and water and for chlorinated solvents in water colorimetric kits for the detection of lead kits for a wide range of water quality parameter manufactured by Hach Company. 

Because the molecular basis of enantioselectivity is poorly understood, directed evolution seems to be an excellent choice for engineering enantioselective biocatalysts. Several impressive examples have been documented. In a classical study, Reetz and coworkers used error-prone PCR coupled with a 96-well plate based colorimetric screening method to increase the enantioselectivity of a Pseudomonas aeruginosa lipase toward 2-methyldecanoate. After several rounds of directed evolution, the enantioselectivity of the lipase increased from E = 1.04 (2% enantiomeric excess) to E = 25 (90-93% enantiomeric excess, ee) (E is the enantioselectivity factor). Using a similar approach. 

Seven different bacterial sialidases, including six commercially available sialidases from Arthrobacter ureafaciens, Clostridium perfingens. Streptococcus sp. IID, Vibrio cholera. Salmonella typhimurium, and Streptococcus pneumoniae, as well as PmSTl which also possesses sialidase activity (20), were used as model systems to test the application of the sialoside library and the 96-well plate based high-throughput colorimetric screening method. 

Wang D.Wang J, Wang B,Yu H. A new and efficient colorimetric high-throughput screening method for triacylglycerol lipase directed evolution. Mol Catal B Enzym 2012 82 18-23. 

We have developed chemiluminescent immunoenzymatic assays for (3-ago-nist drugs in the 96-well-microtiter-plate format. Such competitive assays have been used for determination of clenbuterol and of the overall content of p-agonist drugs in the sample. They matched the standard requirements of precision and accuracy, and were more sensitive compared to the conventional colorimetric methods. Moreover, CL detection was very rapid, making these assays suitable for screening analysis. 

Syoyama and Nogima reported a colorimetric method for the detection of procaine in urine, where the drug and other phenethylamines were extracted [46]. The extraction involved ion association with Chrome Azurol S (C.I. Mordant blue 29), and was applied to a screening test for the drug and other related amines. 

Another sensitive colorimetric procedure is that of Mackenzie et al (1967), which utilizes the dye Rhodamine B to form benzene-soluble complexes with fatty acids. Nakai et al. (1970) developed a rapid, simple method for screening rancid milk based on the foregoing procedure. The test is said to detect rancid milk with an ADV above 1.2. Like the copper or cobalt soap method, the Rhodamine B reagent is also limited to the longer-chain fatty acids. Kason et al (1972) used the method employing Rhodamine 6G of Chakrabarty et al (1969) to investigate... 

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