An automatic technique for the routine fractionation of the urinary hydroxyproline containing peptides

A fully automatic method permits fractionation in a Biogel P2 column of the hydroxyproline-containing peptides into two fractions. The alkaline hydrolysis and the colorimetric evaluation of the liberated hydroxyproline are also completely automatic and allow calculation of the percentages of the two fractions. The first one, termed F1 fraction, contains the peptides of molecular weight larger than 1500, while the other, termed F2, contains the smaller peptides. The method was used for 223 assays. The F1 fraction is decreased in cases of Paget's bone disease. It is increased in cases of metastatic cancer of bone. Statistical analysis of the data demonstrates that this techique greatly improves the certainty of diagnosis when coupled to the assay of total hydroxyproline. When both total urinary hydroxyproline and the F1 fraction percentage are increased over threshold values of 485 mumol per 24 h and 28.4% respectively, the probability of the presence of a bone metastasis is 100%.