A simple method for the separation and quantification of urinary porphyrins

A simple routine method for the separation and quantification of urinary coproporphyrin and uroporphyrin using anion-exchange resin columns is described. The coproporphyrin is first removed from the urine by ether extraction. The anion exchange resin column is then used to isolate the uroporphyrin from the aqueous residue. The proposed method is compared with an existing method developed by Rimington in terms of recovery and reproducibility. Results from 15 urine specimens analysed by both methods are compared. The proposed method yielded lower values for coproporphyrin and higher values for uroporphyrin than the established method, but there was a good correlation between the two methods. This and its relative simplicity make it suitable for routine use.