Densitometry description

This experiment is based on the use of a Kontes fiber optics densitometer (K-49500) with baseline corrector and strip-chart recorder. The description given in the second paragraph of Experiment 8, Section 8 is based on the use of that equipment. Readers will have to modify their approaches to in situ densitometry based on the available instrumentation in their laboratories. In our laboratory, we no longer use the K-49500 model and do most of our lipid in situ densitometry with either a Kontes Model 800 densitometer equipped with a Hewlett-Packard Model 3992A integrator/recorder (Morris et al., 1987) or a Shimadzu CS-930 computerized TLC densitometer operated in the single-beam, reflectance mode. [See Morris et al. (1987), Park et al. (1991), and Masterson et al. (1993) for further information on the use of these instruments in lipid quantification by TLC-densitometry.]... 

TLC coupled with spectrometry and other analytical methods, video documentation, and computer imaging (Chapter 9) quantification by video densitometry (Chapter 10) validation of quantitative results (Chapter 11) and in situ instrumental measurement of radioactive zones (Chapter 13). The fomth edition continues to provide extensive coverage of sample preparation in Chapter 3. We believe that this coverage is unique and differs from that found in other available treatises on TLC. Because of the primary importance of commercial precoated plates, detailed instructions for preparing layers were removed (Chapter 3), and description of documentation by contact printing has been eliminated (Chapter 9). 

Quantification of lipids mainly by in situ densitometry has been described, and a detailed description has been provided of this procedure from the author s work on the quantification of cholesterol in hen s egg yolk (87). In situ quantification techniques continue to become more automated and will be used more frequently in the future for lipid analyses in clinical, industrial, and research labs. 

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