An Ether Extraction Method for the Determination of Urine Phenols

Experiments previously reported from this laboratory (1) have shown that less than 1 per cent of the “total diazo” value of the blood is actually made up of phenols, the reactive substances being almost exclusively etherinsoluble and presumably nitrogenous in nature1 (2). In the present work, an attempt was made to develop more specific methods for the determination of the various groups of urinary phenols. This objective was attained by continuous ether extraction of urine at different pH levels. In this manner the more truly phenolic bodies are separated from the etherinsoluble but diazo-reactive substances in the urine. In addition, these phenols and aromatic hydroxy acids are obtained in separate fractions available for analysis with diazotized p-nitroaniline. Apparatus and ReaqentsInterchangeable glass joints are necessary, since corks or rubber connectiong persistently yield phenolic or diazo chromogenic material. The extraction apparatus consists of four parts. (I) A 500 mm. No. 2800 West type of condenser with outer standard tape? 24/40 joint at the top, and inner 24/40 joint at the bottom; a No. 7580 solid glass stopper (standard taper 24) rests loosely in the top of the condenser.3 (2) The extraction tube,4 which consists of a 30 mm., outside diameter, tube narrowed at the upper end and sealed to the outer part of a 24/40 interchangeable joint. Into the lower end of the 30 mm. tube is sealed, coaxially, an 11 mm., outside diameter, vapor flow and liquid return tube. This tube extends upward about 125 mm. and downward 60 mm. to the 14/35 inner part to which it is sealed. The length of the body of the large extraction tube is