Search

Zur Chromatographie der Harnaminosauren wird eine Zweischichtenplatte vorgeschlagen, um die zeitraubende Entsalzung der einzelnen Harnproben auf Ionenaustauschersaulen zu umgehen. Ein 2 cm breiter Schichtstreifen besteht aus Cellulose mit 10% stark saurem Kationenaustauscher; der Rest der Platte ist mit reiner Cellulose beschichtet. Die Harnproben werden auf die Austauscherschicht aufgetragen, Neutralstoffe und Sauren durch Abspulen mit Wasser entfernt. Die Aminosauren werden mit Methanol/Ammoniak/Wasser (50∶15∶35) in die Celluloseschicht geschoben. Nach Entfernung des Austauscherstreifens wird mit Butanol/Aceton/Eisessig/Wasser (35∶35∶10∶20) zweimal 7,5 cm hoch entwickelt. An Beispielen wird demonstriert, das die Methode fur Screening-Zwecke brauchbar ist.

Thin-layer Chromatographic screening methods for anomalies of carbohydrate metabolism are described. For detection of anomalies with an increased plasma concentration of fructose and galactose in plasma or serum is one-dimensionally chromatographed on precoated plates without deproteinization. For detection of an abnormal urinary or faecal excretion urine (without desalting) or faecal extracts are two-dimensionally chromatographed together with an internal carbohydrate standard. Both methods are relatively simple and yield reproducible results with high sensitivity.

Separation of the amino acids in urine by use of thin-layer chromatography (TLC) has hitherto required that the specimen be first desalted and then chromatographed in two dimensions with at least two pairs of developing solvent systems. We wished to simplify both steps. The customary method of desalting on a column is replaced by desalting on a plate that supports a strongly acid cation-exchanger and a cellulose layer. This method, originally developed for one-dimensional TLC, is used here for two-dimensional TLC. Urine is applied to the ion-exchange layer and strong acids and neutral substances are removed with water. The amino acids are then chromatographed into the cellulose layer, and are separated there two dimensionally with a newly devised pair of developing solutions. This pair of solvents separates nearly all of the amino acids in urine.

A thin layer chromatography (TLC) screening test is described, which allows the semiquantitative determination of HMMA in urine samples. From the collected 24 hour urine a measured sample is applied without extraction to a special TLC plate, which is developed in one dimension. In comparison to a series of graded standard solutions the daily HMMA output can be estimated semiquantitatively. In 102 patients over 18 years of age, suffering from high blood pressure, the daily HMMA output was estimated by both the Pisano method (Pisano, J.J., Crout, J.R. & Abraham, D. (1962), Clin. Chim. Acta 7,285--291) and the TLC method. Coincident results with both methods were obtained in 99 of these cases. The residual 3 cases show pathological results with the Pisano method and results in the normal range or the warning range, respectively, with the TLC method. These cases can probably be classified as false positive results of the Pisano method. The TLC method is recommended as a screening test for estimating the daily HMMA excretion.

A thin layer chromatography (TLC) screening test is described, which allows the semiquantitative determination of HMMA in urine samples. From the collected 24 hour urine a measured sample is applied without extraction to a special TLC plate, which is developed in one dimension. In comparison to a series of graded standard solutions the daily HMMA output can be estimated semiquantitatively. In 102 patients over 18 years of age, suffering from high blood pressure, the daily HMMA output was estimated by both the Pisano method (Pisano, J.J., Crout, J.R.Abraham, D. (1962), Clin. Chim. Acta 7,285--291) and the TLC method. Coincident results with both methods were obtained in 99 of these cases. The residual 3 cases show pathological results with the Pisano method and results in the normal range or the warning range, respectively, with the TLC method. These cases can probably be classified as false positive results of the Pisano method. The TLC method is recommended as a screening test for estimating the daily HMMA excretion.

A two dimensional thin layer Chromatographic method for screening of urine samples for amino acid anomalies is described. In this method very small urine samples equivalent of 0.5 μg creatinine are directly chromatographed without desalting together with an internal amino acid standard. This method yields chromatograms with reproducibly located spot patterns. The detection limit for most of the amino acids is in the range of 250–500 μg/100 ml urine. About 40 amino acids and other ninhydrin positive substances can be identified on the chromatograms. Because of simple procedure, of simple identification, and of good sensitivity the test is a useful tool for screening programs.