Rapid Test Kits

The monitoring systems for IDD defined and recommended by the WHO (2001) include external monitoring by governments, internal monitoring by producers and distributors, and monitoring at the household level. Basic steps to assess iodine intake at the household level are cross-sectional surveys and community-based monitoring (e.g., qualitative rapid test kits used by nutrition officers and others). 

The NADH is produced in stoichiometric amormts and has an absorption coefficient of 6.3 m mol cm at 340 nm. Kits are available that contain all the reagents and instructions (for example, see http // www.r-biopharm.com/. AOAC Intemational (Association of Official Analytical Chemists) also has an index of rapid test kits http //www.aoac.org/testkits/tkdata8. htm). 

To ensure microbial strains are viable and pure a suite of morphological, biochemical, and cytochemical tests are used to confirm characteristics specific to their taxons. A number of commercially available rapid identification kits are also employed for some common genera. In addition to these taxon specific tests, many of the cultures are tested for their fatty acid methyl ester (FAME) profiles using the commercial MIDI system. The FAME profiles can be compared to the MIDI database for species identification/confirmation purposes. The Biolog system, which yields a metabolic fingerprint of an organism, is another alternative for rapid identification. 

According to the practical equipment there are useful tools, so-called test kits, which are units that contain all the reagents and a simple instrumentation in form of plates, tubes and wells. The test kits work rapidly, are easily to handle and field-portable. Frequently, biochemical principles are applied, especially immunoassay techniques which use body-antibody reactions. 

Ruider and Spatzierer [57] described a simple method for the rapid estimation of nitrogen and phosphorus. They discuss the usefulness of test kits for ammonia nitrogen, nitrate nitrogen and phosphorus. 

Hermann (2000) described a rapid automated method involving generation of a known amount of free radicals and the detection of the excess by photochemiluminescence. Test kits are available for determination of total water-soluble antioxidants, fat-soluble antioxidants and ascorbic acid. A luminometric method was developed for the determination of antioxidative activity and was subsequently applied to anthocyanin and betalaine colour concentrates (Kuchta et al., 1999). The method involved quantification of the interruption in luminescence from the hydrogen peroxide-horse radish peroxidase-luminol system in the presence of antioxidants. 

Two types of kits are discussed in this section, sample collection kits and field test kits. Sample collection kits will generally contain all sample containers, materials, supplies, and forms necessary to perform sample collection activities. Field test kits contain the equipment and supplies necessary to perform field safety screening and rapid field testing of the air, water, and/or soil. Sample collection kits will generally be less expensive to construct than field test kits. Sample collection kits can be pre-positioned throughout a system, while the more expensive field kits may be assigned to specific site characterization teams or personnel. 

A number of different testing kits based on immunoassay technology are available for rapid field determination of certain groups of compounds, such as benzene-toluene-ethylbenzene-xylene (EPA 4030) or polynuclear aromatic hydrocarbons (EPA 4035, Polycyclic Aromatic Hydrocarbons by Immunoassay). The immunoassay screening kits are self-contained portable field kits that include components for sample preparation, instrumentation to read assay results, and immunoassay reagents. 

A variety of miscellaneous elements can also occur in a residual fuel oil fraction. For example, chlorine is present as a chlorinated hydrocarbon and can be determined (ASTM D808, D1317, D6160). A rapid test method suitable for analysis of samples by nontechnical personnel is also available (ASTM D5384) and uses a commercial test kit where the oil sample is reacted with metallic sodium to convert organic halogens to halide, which is titrated with mercuric nitrate using diphenyl carbazone indicator. Iodides and bromides are reported as chloride. 

Polynuclear aromatic hydrocarbons (PAH) are aromatic compounds that contain two or more benzene rings fused together. These substances may be analyzed by HPLC, GC, GC/MS and enzyme immunoassay techniques. The latter is a rapid screening method that may be applied for a qualitative or semiquanti-tative determination Test kits are commercially available for such screening. U.S. EPA (1995) has specified a method (Draft Method 4035) that detects a range of PAHs to different degrees and measures the composite of individual responses to determine the total PAHs in the sample. 

PCBs in soils and wastewaters can be rapidly screened on site or in the laboratory by immunoassay technique (Chapter 1.13). Immunoassay test kits are now commercially available from many suppliers. The samples can be tested at the calibration levels of 1 to 50 ppm. The kit primarily contains antibody-coated test tubes or magnetic particles, assay diluent, PCB-enzyme conjugate, a color-forming substance, and a solution to quench the reaction. The method does not distinguish accurately one Aroclor from another. PCBs can be measured semiquantitatively by comparing the optical density of the color formed in the sample against a set of calibration standards using a spectrophotometer. 

The analysis scheme implemented at the Cos Cob site used three sets of tools hand-held test kits, an on-site mobile laboratory equipped with gas chromatograph/ electron capture detector (GC/ECD) and X-ray fluorescence (XRF), and an off-site laboratory with rapid turnaround capabilities (<48 h for virtually all analyses). By implementing all of these tools at the same time, the project eliminated the need for multiple sampling events and allowed the team to perform additional real-time sampling, enabling the team to delineate the extent of potential hot spots quickly. 

Davey, R. J., Jett, B. W., and Alter, H. J. (1991). Pooling of blood donor sera prior to testing with rapid/simple HIV test kits. Transfusion, 31, 7. 

The Gen-Probe Mycoplasma TC Rapid Detection System (Eurogenetics) employs the principle of nucleic acid hybridization to detect mycoplasma in tissue culture. Using in-solution hybridization of ribosomal RNA it is possible to detect positive samples in 3 h or less. The test kit contains a 3H-labeled DNA probe homologs to mycoplasma or acholeplasma ribosomal RNA. 

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