Swabbing methods using

To minimize disruptions to critical operations, surface sampling should be performed at the stop or the end of operations. Surface sampling may be accomplished by the use of contact plates or by the swabbing method. 

No analytical methods specifically used for the determination of tetryl in biological fluids and tissues were located. One attempt to develop a method for detecting tetryl in animal tissues using high-performance liquid chromatography (HPLC) with ultraviolet (UV) detection was unsuccessful because of suspected metabolism and binding of the parent compound and/or metabolites to macromolecules (Army 1981a). However, methods were located for the detection of the tetryl metabolites, picric acid and picramic acid, in urine and for the analysis of tetryl in hand swabs. Table 6-1 is a summary of methods used to determine tetryl metabolites in urine and tetryl in hand swabs. 

Problems such as swab recoverability or interference with adhesive materials are commonly encountered during the swab selection process. It is imperative that the swab selected be compatible with the diluent, the detergents, and the chemical (active/degradant) and it cannot cause interference with the method used for residue analysis, typically FIPLC and/or TOC. A swab recovery study is required for determining the acceptability of a swab. This is performed by spiking the swab with known quantities of the various chemicals under evaluation for potential carryover. The swabs need to be analyzed by the validated method to be used in the cleaning validation studies. An acceptable level of recovery should be no less than 70% and a correction factor needs to be included in final residue calculations. 

Previously, we tested a manual method using antibiotic-mediated lysis of nontarget cells followed by immuno-magnetic separation with an adenylate kinase (AK) bioluminescence endpoint determination. This 4 h assay for patient swabs was carried out on a limited number of samples. The work reported here was to introduce automation into the assay and to carry out tests on a larger number of samples in a hospital setting. Initial assay development was done in a non-clinical laboratory using spiked samples. The assay was then adapted to fit in with the standard hospital test. Modifications were introduced as testing in the hospital laboratory proceeded. 

Where aseptic operations are performed monitoring should be frequent using methods such as settle plates, volumetric air surface sampling (e.g., swabs and contact plates). Sampling methods used in operation should not interfere with zone protection. Results from monitoring should be considered when reviewing batch documentation for finished product release. Surfaces and personnel should be monitored after critical operations. 

Method The method used is extraction of viral DNA from different tissue types, swabs or body fluids, followed by PCR. 

This is a clear liquid that vaporizes and, on contact with damp air, combines with w ater to produce a dense acid mist. Titanium tetrachloride can be painted on to surfaces, such as fume cupboard sills, from which it will evaporate over a period of several seconds showing the airflow patterns close to the surface. (Airflow patterns close to a surface could also be visualized by fastening short filaments of wool or cotton to the surface). Titanium tetrachloride can also be used, when soaked onto a cotton swab, in a similar way to a smoke tube. It is a simple and inexpensive method but the production of smoke, which is toxic and corrosive, is uncontrollable. 

Brush plating is a special technique which dispenses with a container and uses a swab soaked in electrolyte applied to the work. In jet plating a stream of electrolyte is applied to the cathode. Both are methods of selective plating, applying an electrodeposit to only a part of an article. Little has been published about the techniques or the properties of coatings they produce. 

It is possible to also test semi-solid antibacterial preparations on the skin itself, as described for liquid disinfectants (section 3.5.1). A portion of the skin— the backs of the fingers between the joints is a useful spot— is treated with the test organism, the preparation is then applied and after a suitable interval the area is swabbed and the swab incubated in a suitable medium. Alternatively, the method employing pig skin, described in section 3.5.1, may well be adapted to the problem of testing semi-solid skin disinfectants. 

May be sterile fer use in ceriain circumstances Absorbent cotton wool Swabbing, cleaning. Any method... 

The first mechanical variant uses a presoaked cotton swab on the surface covered with the disinfectant solution, the second variant uses a presoaked swab without disinfectant on the test surface. Both methods have been tested by Prof. Koller in Vienna and the first variant showed a higher efficacy than the second (using more disinfectant on the surface). 

It may be desirable to first clean the pipeline with a polyurethane foam swab. This material can be purchased commercially either in specific cut sizes, or in bulk, which can be cut to the desired size. Swabs will effectively remove soft scales and loose material. Their method of use is identical to that of the pig. 

Fig. 20.2 Pheromone delivery in Desmognathus ocoee salamanders and the method of pheromone delivery used during behavioural trials. A receptive female places her chin on the tail base of the male and typically straddles his tail. The male turns back towards the female and places his submandibular mental gland on her dorsum. The male then uses his premaxillary teeth to scratch the site on her dorsum that he has swabbed with his mental gland secretions. To mimic pheromone delivery in behavioural trials, each male was deglanded and a treatment solution was delivered to each female in a treatment patch (TrP) placed on her dorsum just posterior to the head. Photograph by Stevan J. Arnold...

Of the explosives listed in Table 4, only those such as NG with vapour pressures greater than 10 Pa at 25°C are good candidates for the direct detection of vapour by current instrumental techniques. However, vapour pressure rises markedly with temperature. In addition, consideration of the thermal stability data in Table 4 offers the possibility of heating samples containing traces of involatile explosives such as RDX or PETN to increase their vapour pressure and render them detectable. This is the basis of the common technique of combining a heated inlet system with a vapour-type detector, for example, the method of desorption from a swab on a heated stage often used with IMS or TEA systems. This approach has greatly broadened the scope of what were previously viewed as vapour-type detectors and is now standard practice such instruments are now known as particle detectors. 

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