Non-chromatographic methods

In addition to online resources, other texts and references have discussed the process of validation for methods used in the pharmaceutical industry in relation to the regulatory guidance documents. These guides include discussions on method development in relation to method validation, the validation of non-chromatographic methods and stability indicating methods. 

Miscellaneous Non-Chromatographic Methods of Analysis Chromatographic Methods of Analysis... 

Describe a non-chromatographic method for the separation of the enantiomers of rac- 1-phenylethanamine. 

The central cavity of the cylinder-shaped cyclodextrins behaves as an empty capsule It can accommodate so-called guest molecules of appropriate size, shape, and polarity. This "molecular encapsulation" can be utilized for stabilization and for enhancement of solubility of drugs, vitamins, flavors, etc., and utilizing the selectivity of the inclusion complexation, it can be applied for separation of substances, either by non-chromatographic methods, or chromatographic methods. 

A large number of studies on non-chromatographic methods of surface separation of dissolved substances (molecules and ions) and highly dispersed particles (colloids and other small particles) to which the principles of common flotation are inapplicable, have been... 

Results obtained with colorimetric methods are highly empirical. Estimations of total PAs are often expressed as catechin or epicatechin equivalents, which make the data difficult to interpret and compare across different samples. Qualitative data such as subunit structures, interflavan bond types, and proportions of oligomers with different degrees of polymerization - is not available with any of these non-chromatographic methods. 

At very large scales non-chromatographic methods, such as chiral synthesis. should also be considered. Often the best method involves a combination... 

It is concluded from the above that apart from being a method for determining simple oxidation products, gas chromatography makes it possible to control oxidation and to optimize it compared with non-chromatographic methods. 

Compounds Eluted with Sodium Dodecyl Sulfate Mobile Phases on a CIS Column [31] compared to non-chromatographic methods. 

Clearly the best-known non-chromatographic method for the separation of enantiomers, the so-called classical resolution, involves combination of a racemate and an enantiopure compound to form diastereomers that can be separated based on physical properties and the enantiomericaUy pure compound re-isolated (Scheme 1.1). 

Table 4.8. Comparison of adsorption enthalpies kJ mor ) of gases on carbon as measured bg chromatographic and non-chromatographic methods [17]...

It is assumed that calibration curves are determined from the same type of matrix in which the analyte is to be determined. Although calibration of the mass spectrometer for each assay is accepted as necessary, calibrating the analytical procedure for each assay is more controversial. A method to assess the significance of interferences is the calibration curve. If the calibration curve is linear through the lowest calibration point, then the interference is not considered to be significant. External standard methods tend to be used with non-chromatographic methods of introducing the sample into the mass spectrometer. 

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