Triglyceride blanks

The equation assumes an average molecular weight of 885 g/mole (triolein) for plasma triglycerides. In addition, because of the preliminary extraction and adsorption steps, the CDC reference method measures only the glycerides, and does not include free glycerol, the so-called triglyceride blank. 

Although triglyceride blanks can in most cases be ignored in clinical measurements, they can dramatically affect conclusions about method accuracy, important in cahbra-tion or in standardization of triglyceride measurements. For example, participation in the CDC standardization program requires use of a blanking method, several of which... 

The overall CVs are slightly higher for triglycerides, probably because of the contribution of triglyceride blanks and the inherent greater variability in triglyceride methods, but the bias has improved considerably in recent years. The performance in the calculated LDL cholesterol values is encouragmg and reflects the improvement in the reliability of the primary measurements. Data are also now available for the measured LDL cholesterol. Both the overall CV and bias for the measured LDL cholesterol are inferior to those of the calculated values. 

Ceriani, R. L., Peterson, J. A., Lee, J. Y., Moncada, R. and Blank, E. W. 1983. Characterization of cell surface antigens of human mammary epithelial cells with monoclonal antibodies prepared against human milk fat globule. Somat. Cell Genet. 9, 415-427. Christie, W. W. and Wooding, F. B. P. 1975. The site of triglyceride biosynthesis in milk. Experientia 31, 1445-1447. 

E514 Earl, R.E., Studts, D.J. and Markin, R.S. (1989). Glycerol blanked triglyceride measurement on the Hitachi 705 chemistry analyzer. Clin. Chem. 35, 1072, Abstr. 34. 

Glycerol blanking of triglyceride measurements must be done in laboratories participating in the CDC Lipoprotein Standardization Program and is recommended for laboratories that specialize in assessment of lipid status, have large populations of hyperlipidemic subjects, or participate in clinical or basic research. 

Glycerol blanking of triglyceride analyses does not have to be routinely conducted on outpatient samples unless economically feasible. However, because of the potential for higher glycerol concentrations in hospital inpatient specimens, all inpatient specimens should be routinely glycerol blanked. 

Cole TG. Glycerol blanking in triglyceride assays is it necessary Clin Chem 1990 36 1267-8. 

Although plasma lipoproteins have been used to assay phospholipid transfer, they are more commonly used to study the exchange and transfer of cholesteryl ester and triglycerides by transfer proteins in plasma. The general protocol for the assay is similar to that for the phospholipid experiments previously described, except that nontransferable markers are not commonly used. As a result, the accuracy of the assays depends upon high recoveries of noncontaminated lipoproteins or on the use of a blank incubation in the absence of transfer protein. 

The spectrum of a mixture of cholesterol and tributyrin in CCI4 in concentrations of 0.01 M and 0.25M, respectively, is shown in Fig. 5.6, curve 4. In addition to the OH band at 3620 cm S a new band is present at 3540 cm . At this concentration cholesterol exists only as a monomer, as shown in curve 1. Since the spectrum was recorded against a blank solution containing the triglyceride at the same concentration as in the mixed solution, it is obvious that the new band is not due to either component alone. The figure also shows that the intensity of the OH band of cholesterol at 3620 cm in the mixture is less than that in the pure solution (curve 1). Thus, the new band was due to a hydrogen-bonded complex between cholesterol and the triglyceride. 

Castor oil contains a triglyceride of ricinoleic acid which is hydrolyzed by intestinal lipases to glycerol and ricinoleic acid, which has cathartic effects. Allergic reactions such as angioedema, rhinitis, asthma, and scarlatiniform rashes have been described but seem to be rare reactions to this common laxative (Bennett and Schwartz 1934 Blank 1945). 

W. J. Blank, Rubbery Polymeric Mixtures Comprising a Maleinized Type Oil, U.S. Pat. 3,719,623 (1973). Semi-IPN or grafted IPN. Triglyceride oil and melamine deriva-tive/styrene-maleic anhydride half ester. 

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