Swab tests, equipment

Isolators should have sufficient service port penetrations to allow as much equipment to be placed outside of the isolator as possible. Traditionally control boxes, chillers, keypads, and printers were placed as close to the analytical instrumentation being used as possible. The amount of equipment in direct contact with the samples should be minimized. If equipment needs to be placed in the isolators, the only way to remove that equipment later is to prove that the equipment has been cleaned to acceptable levels by swab testing. Based on experience, this cleaning is difficult to accomplish and in many cases the equipment needs to be considered contaminated and discarded if there is a need to remove it from the isolators. 

Cleaning validation is different in the pilot plant environment than in manufacturing.Again, the lack of process repetition often creates the need to verify that equipment is clean before and/or after the manufacture of batches used in clinical studies on a per batch basis. This can be accomplished by swab testing critical product contact surfaces before and/ or after equipment use to ensure that residual drug is absent or at an acceptably low level. Cleaning... 

Many times swab samples have to be taken at a remote location where the equipment necessary for the analysis may not be available. Because the samples would be in transit for 24-48 h, an alternative to using test tubes for sample transport was investigated. Screw-cap scintillation vials either with a polyethylene insert or with an aluminum foil liner in the top of the cap were tested. Four polyester swabs were placed into each vial along with 10 mL of 1.00 pg/mL 50 50 ethanohwater solution of clarithromycin or 10 mL of 50 50 ethanohwater. The vials were capped and then shaken to wet the surface of the vials. Half the vials were refrigerated and the other half were left at room temperature on the... 

Take the swab stick from the tube and gently swab 25 cm of area (walls, floor, equipment, etc.) and place back in tube containing 5 mL sterile buffer and test or incubate per official procedure. 

For purposes of the calculations, let s assume that we have a large tank equipped with a mixer, a valve, and a dip tube. Let s further assume that we have carried out the calculations and we know that our acceptance criteria allow us a total residue of 100 mg. The tank has a manway gasket that we have identified as a worst-case location, and in the first example we are going to base the entire test on the single worst-case location. Suppose we swab an area of 2 in. by 2 in. (total of 4 sq. in.) and on analysis we find there is 0.1 mg on the swab. If the tank has a total surface area of 100,000 sq. in. we could calculate the total residue on the tank using the data from the single swab as follows ... 

The analytical sequence for trace samples involves a physical description of the item, followed by sample collection and instrumental analysis directly. Trace samples are analysed while using all of the precautions required to prevent contamination of materials. The laboratory, equipment, chemicals and operators must be demonstrably free of cannabis and should be tested prior to sampling of the casework materials. The latter should then have samples taken from them. This is usually undertaken by swabbing part of the surface to be considered with a cotton wool swab soaked in ethanol. The latter is used because the cannabinoids have been demonstrated to be stable in this solvent and to be freely soluble. While the cannabinoids are stable in diethyl ether, the more polar acids are not freely soluble in this solvent. While chloroform is a solvent in which the cannabinoids are freely soluble, it should not be used because it contains HCl which is known to catalyse the breakdown of the cannabinoids. 

Decisions regarding the choice of a specific amplification test for the detection of CT and GC should not be based solely on the cost of reagents. Other key factors to consider include test performance characteristics, such as diagnostic sensitivity and specificity, and whether the test has been cleared for urine and swab specunens in both symptomatic and asymptomatic individuals. Ideally the test should include an internal control, particularly if a crude lysate is used in the assay. Other factors to consider are degree of automation, ease of use, work flow issues, and space and equipment needs. 

As part of the validation of the cleaning method, the cleaned surface is sampled for the presence of residues. Sampling should be made by an appropriate method, selected on the basis of factors such as equipment and solubility of residues. For example, representative swabbing of surfaces is often used, especially in areas that are hard to clean or where the residue is relatively insoluble. Analysis of rinse solutions for residues has also been shown to be of value where the residue is soluble or difficult to access for direct swabbing. Both methods are useful when there is a direct measurement of the residual substance. However, it is unacceptable to test rinse solutions (such as purified water) for conformance to the purity specifications for those solutions instead of testing directly for the presence of possible residues. 

The injectivity test was initiated in August, 1983. Well 152 and two adjacent wells were equipped with surface readout pressure sentries. The two adjacent wells were shut in and used for reservoir pressure monitoring. Polymer injection was initiated using 750 ppm Cyanatrol 970 at 1,500 BWIPD. Pressure falloff tests and swab samples were obtained on 8/24/83 (4,447 bbl polymer injected), 9/12/83 (25,580 bbl), and 10/6/83 (67,398 bbl). 

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