The Application of the Differential pH Method to the Biochemical Evaluation of Seminal Plasma

Objective: To apply the differential pH method to the biochemical evaluation of seminal plasma. Design and Methods: Fructose, citric acid and free L-carnitine concentration in human seminal plasma were measured by the differential pH method. These are routinely taken as markers of seminal vesicle, prostate and epididymal function, respectively. The pH differential method was then compared with standard spectrophotometry. Results: The linearity, recovery and imprecision calculation for each assay were found to be reliable and the method correlated well with the reference spectrophotometric technique. In addition, the pH differential method showed certain advantages compared to spectrophotometry: a) speed of procedure (40 to 120 sec/assay); b) ability to measure the analytes even in small volumes of seminal plasma (10 μL to 50 μL) without deproteinization or dilution, thus eliminating manual operations. Conclusions: The differential pH method is an innovative approach to the biochemical assessment of seminal plasma.