Colorimetric test kits

For the group of sensors and portable instruments, the cost assessment is illustrated for an UV photometer, a colorimetric test kit as well as a multi-parameter probe... 

Because of the relative instability of chlorinated water samples, determination in the field is often required. Colorimetric test kits are available commercially for this purpose. 

Different colorimetric test kits are available for the estimation of active chlorine. Bosch et al. [3] compared the performance of different colorimetric reagents for the determination of residual chlorine in water samples. The 3,3 5,5 -tetramethylbenzidine reagent produced the best results in the pH range of 1-2. In this case, the absorbance was measured at 450 nm and the detection limit was 2 ng/cm. ... 

Hormones Androgens Testosterone Testosterone EIA kit Salivary assay test Colorimetric EIA kit Testosterone ELISA kit Immunometric Ltd. Salim etric Assay Designs Inc. Oxford Biomedical Research http //www.oxfordbiomed.com/... 

Fig. 12. Effect of spontaneous apoptosis on the activation of caspase-3 in human eosinophils. Eosinophils (2 x 10 /ml) were cultured for 3 h. Cells were lysed and caspase-3 activity was measured by caspase-3 colorimetric assay kit (R D Systems). Enzymatic products were measured at 405 nm with BIOTEK EL340 ELISA microplate reader (BIO-TEK Instrument Inc., Vermont). Human recombinant caspase-3 (5 U) (Calbiochem, California) was used as a positive control. The stimulation index was determined by direct comparison to the level of the normal control. Background readings from cell lysates and buffers were substracted from the readings of both induced and uninduced samples samples before calculating the stimulation index in caspase-3 activity. The differences between control and treated groups were assessed by Student s i-test. P < 0.05 P < 0.001 (Z2).

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. 

Colorimetric Colorimeter ca. Test kits, kit reagent Preparation and... 

A simple test for ether peroxides is to add lOmL of the ether to a stoppered cylinder containing ImL of freshly prepared 10% solution of potassium iodide containing a drop of starch indicator. No colour should develop during one minute if free from peroxides. Alternatively, a 1% solution of ferrous ammonium sulfate, O.IM in sulfuric acid and 0.0IM in potassium thiocyanate should not increase appreciably in red colour when shaken with two volumes of the ether. Merck-Chemicals supply peroxide test kits (Perex Test) which use a colorimetric method with test strips which can be used to estimate the amount of hydrogen peroxide, from as low a concentration as... 

Keen visual observation is the most important task during a site reconnaissance. Flowever, some basic in-held chemical testing equipment is useful. Commercial kits are available, mainly based on colorimetric reactions. These kits can be used to check for the presence or absence of common contaminants and to measure soil pH. However, the results obtained using these test kits should only be regarded as qualitative, not least because samples taken at the surface may not represent the bulk of materials on the site. For site reconnaissance, the use of in-held instrumental testing is not justihed. An exception is hand-held equipment to test for the presence of gaseous and volatile contamination—photo-ionisation and other detectors are useful where such contaminants are anticipated. While a Phase la study does not normally include intrusive investigation, a small number of samples may be taken for laboratory analysis. These can be important when waste and other potentially contaminated materials of unknown composition have been spread, deposited or are stored on the site. 

Several field sereening test kits are available for the detection of TNT in soil and water. The most common methods can be categorized into immunoassay and colorimetric based methods. Strategic Diagnostics [4] has two immunoassay based methods commercially available in the market ... 

A qualitative colorimetric test based on the inhibition of AChE can screen the presence of OPs and CMs. The thioesters of OPs have to be activated by a dilute bromine solution. Cummercial test kits are available for the coiori-metrie lest from Strategic Diagnostic. 

The Chemical Agent Water Test Kit M272 consists of colorimetric detector tubes and enzyme impregnated detection tickets for nerve agent detection. The kit is designed to detect the presence of chemical agents in water samples. 

The serum GOT and GPT activities were measured using the colorimetric test reported by Reitman and Frankel with S.TA-test Wako kits from Wako Pure Chemical Industries, Ltd. (Osaka, Japan). 

Colorimetric field tests for TATP and HMTD were described in Section 5 dealing with peroxide-based explosives. This group contains Keinan s PEX [85] (E. Keinan, Personal Communication, February 2006) and the kit developed by Schulte-Ladbeck et al., which involves also a preliminary stage to avoid falsepositive responses by non-explosive peroxides [86]. The color change of molybdenum hydrogen bronze suspension upon reaction with TATP was recommended also as a field test. Exposure of filter paper strips which were soaked in butanol suspension of the molybdenum compound to TATP or hydrogen peroxide vapors rapidly bleaches the blue color [87, 88]. 

Is a colorimetric-tube system designed specifically to detect and identify military agents. To complete the series of tests requires approximately 24 minutes. It is about 20 times less sensitive than the M256 kit and is no longer employed by the U.S. military. 

Carbofuran Metabolite Assay. Rapid detection of enhanced degradation of carbofuran in soil can be accomplished in two different manners. The first approach is to measure the actual amount of carbofuran remaining after application and compare this value with what might be expected to remain after a selected time. This concept has been used by FMC in the form of a test ticket that colorimetrically determines the amount of carbofuran based on inhibition of acetylcholinesterase. The diagnostic kit is manufactured by Enzy-Tek of Lenexa, KS (20). A disadvantage of this method is lack of specificity due to the ability of the test reagents to react with other soil insecticides and their metabolites that are also acetylcholinesterase inhibitors. 

The basis for the standard method for determining blood (ChE) inhibition is the measurement of the enzymatic products derived when either acetylcholine or acetylthiocholine are used as substrates. The rate of formation of acetate is measured by changes in pH, while the formation of thiocholine is determined colorimetrically. A portable device utilizing this method, the Test-Mate OP Kit (EQM Research Incorporated, 2585 Montana Avenue, Cincinnati, OH 45211), provides a rapid, reasonably sensitive assay for ChE inhibition following OP exposure. The kit should be appropriate for emergency contingencies, and only very small blood samples are required. Military forces are viewing such a portable kit as a means to screen... 

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