Tube diffusion test

The fate of tubercle bacilli or E. coli in human or bovine serum was determined not only by the use of the agar-plate diffusion test but also by experiments performed in serum-containing test tubes. In tube experiments, serum is inoculated with bacterial suspensions adjusted to contain a known number of bacteria in the inoculum. Infected sera are incubated at 37 °C and, after various periods of time, bacterial numbers are determined by plating the samples on the growth-supporting IPAM. The number of developed colonies on agar medium shows the number of bacteria in the experimental tubes. 

Example 5.5.1 Multicomponent Diffusion in the Loschmidt Tube Another Test... 

Among the diffusion tests, the very thoroughly evaluated ANS 16.1 (American Nuclear Society (Cote and Isabel 1984) leach test should be mentioned. In the Dutch Tube Procedure (Van der Sloot et al. 

The KIS test is marketed for use at either abattoirs or laboratories for the analysis of kidney samples to identify animal carcasses with non-compliant concentrations of antimicrobial residues present in the edible tissues. The KIS reagents are supplied as self-contained and pre-measured for a single use presented in a disposable swab format. The swab is directly inserted into an incision made in the kidney test sample to collect a sample of the serum for analysis via microbial inhibition. The impregnated swap is then inserted into a device containing a tube diffusion MIA... 

As a general observation, all the tube-diffusion based MIAs currently available show broadly similar detection capability profiles and comparable performance characteristics. However, the applicability of such tests can be more readily determined on the basis of other parameters such as the robustness and reliability (false compliant/non-compliant rates). Other features, such as the nature of the sample preparation (especially important for the analysis of solid samples, e.g., tissue and feeds) and the potential for automation, are important considerations when choosing to implement a commercial MIA for multi-residue screening. 

Sterile graduated pipettes of 10, 5, 2 and 1 ml, sterile capped 7.5 x 1.3 cm tubes/ small screw-capped bottles, Pasteur pipettes, an overnight broth culture of the test and control organisms (same as for disc diffusion tests), the required antibiotic in powder form, the required solvent for the antibiotic, sterile distilled water - 500 ml and suitable nutrient broth medium. A suitable rack to hold 22 tubes in two rows, i.e., 11 tubes in each row. 

In two sensitised workers exposed to diphenylmethane diisocyanate (MDI), used for coating pipes with a polyurethane foam, tests with an MDI-human serum albumin conjugate showed the presence of specific IgE antibodies as measured by polystyrene tube radioimmunoassay (PTRIA) procedures (Zeiss et al. 1979). High levels of specific IgG antibody were found, with some cross-reactivity with a TDI-human serum albumin conjugate. The serum of one of the workers gave a positive precipitin reaction in the double diffusion test in gel. The authors suggest that these antibodies may be related to the respiratory reactions to the inhaled chemical. 

A solution of 44, 43, 9, or 77 (33.0 mM in DMSO, or DMSO only for control experiments) was added to a suspension of phosphatidylcholine liposomes (8.00 mM in pH 7.4 Tris buffer) to give the desired final concentration of sun-soeen molecule (20 mol%, 10 mol% or 5 mol%), in a test tube. The test tube was plugged loosely with cotton wool in order to minimise evaporation but allow the free diffusion of air. The mixture was stirred, in the dark, for 30 min in order to... 

Remick and Geankoplis made flux measurements for both species in the isobaric diffusion of nitrogen and helium through their tube bundle. Pressures spanned the interval from 0.444 nim, Hg to 300,2 ram Hg, which should cover the whole range between the limits of Knudsen streaming and bulk diffusion control. Then, since K and K, are known in this case, the form of the proposed flux relations could be tested immediately by plotting the left hand side of equation (10.15) against... 

In the thin-layer cavity cell technique, a cell is constructed to give a thin cavity on one wall of which the metal-plate working electrode is mounted. This wall is separated by a Teflon sheet in which a central aperture has been cut out, from the opposite wall of the cavity this wall contains entry and exit tubes for the test solution which is caused to flow past the working electrode provision is made for connections to the other electrodes. If the Teflon sheet is thin enough (about 0.05 mm), the distance between the two walls of the cavity is less than the normal thickness of the diffusion layer of the electrolyte when undergoing electrolysis, and so electrolysis within the cavity is rapid.26... 

The permeability tests for alkali metal ions in the aqueous solution were also conducted. When an aqueous salt solution moves to cell 2 through the membrane from cell 1, the apparent diffusion coefficient of the salt D can be deduced from a relationship among the cell volumes Vj and V2, the solution concentration cx and c2, the thickness of membrane, and time t6 . In Table 12, permeabilities of potassium chloride and sodium chloride through the 67 membrane prepared by the casting polymerization technique from the monomer solution in THF or DMSO are compared with each other and with that the permeability through Visking dialyzer tubing. The... 

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