Urea quantification

The continuous measurement of urea in blood during dialysis is an important precondition for optimization and individual monitoring of the treatment of patients with chronic kidney failure. The methods of urea quantification employed so far are time-consuming and have to be... 

Veloso, A. C. A., Teixeira, N., and Ferreira, I. M. P. L. V. O. (2002). Separation and quantification of the major casein fractions by reverse-phase high performance liquid chromatography and urea-polyacrylamide gel electrophoresis Detection of milk adulterations.. Chromatogr. A 967, 209-218. 

Figure 1 Electropherograms of the casein fraction of a mixture of one-third each of bovine, ovine, and caprine miik. Peak identification 1, bovine asi-casein 2, ovine asi-casein 3, bovine K-casein 4, ovine K-casein 5, bovine jS-casein Ak 6, caprine k-casein 7, bovine S-casein A 8, ovine 2-casein and caprine p2-casein 9, ovine j8i-casein and caprine, -casein. Conditions hydrophilic coated fused-silica capillary 50 pm i.d. x 57 cm separation buffer, 6 mol I" urea, 0.32 mol I citric acid, 20 mmol I sodium citrate, pH 3.0, containing 0.5gr methylhydroxyethyl-cellulose applied voltage, 25 kV injection, 15 s temperature, 45°C. (Reprinted with permission from Molina E, Martin-Alvarez PJ, and Ramos M (1999) Analysis of cows , ewes and goats milk mixtures by capillary electrophoresis Quantification by multivariate regression analysis. International Dairy Journal 9 99-105 Elsevier.)...

Bernhard AM, Peitz D, Elsener M et al (2013) Quantification of gaseous urea by FTIR spectroscopy and its application in catalytic urea thermolysis. Top Catal 56 130-133... 

Sherma, J., and Boymel, J. (1983). Densitometric quantification of urea, carbamate, and anilide herbicides on Cig reversed phase thin layers using Bratton-Marshall reagent. J. Liq. Chromatogr. 6 1183-1192. 

Figure 6.9 shows the result of the prediction of the concentration of analytes based on the mid-IR spectroscopy of dried serum samples. Total protein content, lipids, lipoproteins, glucose as well as urea and uric acid can be quantified with an accuracy that is in the medically acceptable range. For example, the prediction error of 10% for the quantification of glucose is clearly within the range of acceptable accuracy as recommended for monitoring diabetes. 

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