Physical Assays

In addition to the water absorption, the shape of the farinogram is used to characterize a flour. Var- 

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There also is the indication that immunoassays allow untrained analysts to run highly sensitive assays. Although immunoassays may be very forgiving and easy to perform, the quality of the data generated for any physical assay will depend upon the... 

A point that may seem fairly obvious, but worth reiterating, is that, with a complex mixture from which one or a few specific compounds are to be isolated, a means of keeping track of the compound through the extraction process is needed. There are two main ways to follow a compound (1) physical assay (for example, HPLC, thin-layer chromatography [TLC], liquid chromatography-mass spectometry [LC-MS], and perhaps involving comparison with a standard), or (2) bioactivity assay. 

If the aim is to isolate a known compound(s), much of this information will already be established, or will probably be apparent from the stmcture. (It may even be that a physical assay exists for the compound and this may provide the basis for an isolation.)... 

A good solution scattering curve is dependent on careful sample preparation, satisfactory biochemical and physical assays, accurate background subtractions, a suitable sample holder and instrumental calibration. Aspects of these five topics are briefly noted. 

After monodispersity tests, the most important physical assay is that of the sample and buffer transmission measurement. These are required for accurate sample-buffer subtractions (below) and for and matchpoint determinations (Section 2.5). Since the neutron transmissions of HjO and H20 range from about... 

Nomenclature and Classification Fat-Soluble vs Water-Soluble Vitamins Vitamin B Complex Vitaminlike Substances Determination of the Vitamins in Food Biological (Animal) Assay Microbiological Assay Chemical Assay Physical Assay Human Assay... 

Physical Assay. Each of the vitamins may now be determined by physical methods—measurement of absorption spectra, chromatography, fluorescence, turbidity, etc. 

Although the standard distillation method can be used, it is unnecessarily lengthy. Direct non-aqueous titration with 0-05N perchloric acid to crystal violet (see p. 792) of about 0 15 g of powdered tablets in the presence of mercuric acetate is possible or a physical assay can be used. 

A direct physical assay can also be applied to this preparation ... 

Preparations of drugs administered by injection or applied under some surgical conditions must of necessity be free from contaminating microorganisms. Therefore, besides the chemical and physical assays on such preparations, tests for sterility are also applied. These tests involve the examination of every lot or batch processed for the presence of aerobic and anaerobic bacteria, and often moulds. 

Parks, W. P., Melnick, J. L., Rongey, R., Mayor, H. D. Physical assay growth cycle studies of a defective adeno-satellite virus. J. Virol. 1, 171-I8O (1967). 

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