Assessment of Compatibility

Compatibility assessment tests aim to evaluate the resistance of a metal or alloy in a given medium such as hypochlorite solution or phenol solution or any other chemical product or media of more complex composition. The method, long in use, is quite simple samples are immersed in the relevant solutions for a defined period of time (hours, days), depending on 

The type of corrosion, if there is corrosion, is detected visually. If the corrosion is uniform, the dissolution rate is determined by measuring the mass loss. This kind of test has evaluated the resistance of aluminium in many media, and the reported results are summarised in Parts E and F. 

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Method for total immersion corrosion test for tank-type aircraft maintenance chemicals Method for total immersion corrosion test for aircraft maintenance chemicals Practice for assessment of compatibility of bio-materials (non-porous) for surgical implants with respect to effect of materials in muscle and bone... 

ASTM F981-99. Standard Practice for Assessment of Compatibility of Biomaterials for Surgical Implants with Respect to Effect of Materials on Muscle and Bone. 1999. 

Zaharescu, T., Assessment of compatibility of ethylene-propylene-diene terpolymer and polypropylene. Polymer Degradation and Stability 2001,73,113-118. 

F1983 Assessment of compatibility of absorbable/resorbable biomatetials for implant applications... 

F 981 Assessment of compatibility of biomaterials for surgical implants with respect to effect of materials on muscle and bone... 

The interactions between drugs and excipients or polymers or between excipients are of vital importance to formulation. Under the assessment of compatibility by DSC or DTA it was suggested that 1 1 blends may be used to maximise any interaction between two materials. This is one of the major limitations of the technique. It does not seek to establish true equiibrium between the materials. A combination of DSC or DTA with HSM provides the best way of establishing the phase diagram. 

There shall be a written assessment of stability based at least on testing or examination of the drug product for compatibility of the ingredients, and based on marketing experience with the drug product to indicate that there is no degradation of the product for the normal or expected period of use. 

To provide a complete assessment of all these variables, the final evaluation of safety must be made in the in vivo model using the preparation under the proposed conditions for use, following tissue compatibility with many of the techniques already discussed. Confocal microscopy is a relatively new noninvasive technique that allows a detailed examination of the endothelium in the live animal, and thus may prove useful in following changes in this delicate tissue over time. As in ex vivo models, the... 

Regional climate should be the first consideration when evaluating the suitability of an alternative landfill cover for a site. If the regional climate appears to be compatible with the requirements of the alternative cover, then site characteristics should be examined to determine whether the site climate is also suitable. Site and regional climate may differ substantially for sites near mountains, in valleys, in the rain shadow of coastal mountains, or near the coast. The Air Force Center for Environmental Excellence commissioned a generic assessment of the suitability of the ET landfill cover based on regional climate for the continental United States.4... 

Besard L, Mommaerts V, Vandeven J et al (2010) Compatibility of traditional and novel acaricides with bumblebees (Bombus terrestris) a first laboratory assessment of toxicity and sublethal effects. Pest Manag Sci 66 786-793... 

The accurate assessment of binary chemical compatibility is an important part of the safe handling, transport and processing of industrial chemicals. The most common and convenient way to represent binary chemical incompatibility is by a simple two-dimensional chart or matrix. Binary compatibility charts are an extremely useful teaching tool for new and even veteran employees. 

Level 1 sampling provides a single set of samples acquired to represent the average composition of each stream. This sample set is separated, either in the field or in the laboratory, into solid, liquid, and gas-phase components. Each fraction is evaluated with survey techniques which define its basic physical, chemical, and biological characteristics. The survey methods selected are compatible with a very broad spectrum of materials and have sufficient sensitivity to ensure a high probability of detecting environmental problems. Analytical techniques and instrumentation have been kept as simple as possible in order to provide an effective level of information at minimum cost. Each individual piece of data developed adds a relevant point to the overall evaluation. Conversely, since the information from a given analysis is limited, all the tests must be performed to provide a valid assessment of the sample. 

As Fig. 15b illustrates, the graphical relation appears to be linear for an interaction number of 3 to 4, if A 1. Alternatively, for A = 1, linearity is evident (Fig. 15c) when the interaction number is 5 to 6. Thus a large value of A is compatible with the smallest interaction number. Excimer formation occurs within the fluorescence lifetime, about 8 nsec. Within that time the pyrene-labeled amine side chains must approach within about 4 A of each other. For the 5.3% pyrenylpolyethylenimine derivative in ethanol, where no ground-state association occurs, the effective local concentration of pyrene on the polymer matrix is about 10-2 M, as calculated from excimer fluorescence. In aqueous solution, where clusters form within the polymer matrix, the effective local concentration of pyrene adduct must be even greater. The quantitative assessment of fluorescence intensities (Fig. 15) points to a minimum interaction number of 3 to 4 pyrenyl-labeled amine side chains, within the 8 nsec lifetime. Since A 1, it appears from (12) that kDM(A) kMD + kD. Thus excimer formation must be very rapid in the polymer environment. We can conclude, therefore, that the primary-amine side chains of poly-ethylenimine are very flexible and mobile. 

Dissolve up to 4 mg of the peptide or hapten to be coupled in 1 ml of the reaction buffer chosen in step 1. If the peptide to be coupled is already in solution, it may be used directly if it is in a buffer containing no other amines or carboxylic acids and is at a pH between 4.7 and 7.2. Note If an assessment of the degree of peptide coupling is desired, measure the absorbance at 280 nm of the 1 ml peptide solution before proceeding to step 3. In some cases, a dilution of the peptide solution may be necessary to keep the absorbance on scale for the spectrophotometer. If the peptide is sparingly soluble in aqueous solution, it may be dissolved in DMSO and an aliquot added to the carrier solution. See the previous discussion on carrier proteins to determine the levels of DMSO compatible with carrier protein solubility. 

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