Effect of Storage Temperature and Time on Urine Electrolyte Assessment

Students: Ethan Pierce, Abbie Cantrell, and Miranda Badolato

Major: Exercise Science

Mentors: Dr. J.D. Adams

Department: Health and Human Performance

Effect of Storage Temperature and Time on Urine Electrolyte Assessment

Urine specimens are widely analyzed to produce multiple indices of renal health and are being collected and stored as part of standard protocols for large cohort studies and small experimental trials. In spite of this, there are no clinical guidelines for the storage of urine electrolytes. Therefore, the aim of the present investigation was to examine the effect of various temperatures and storage times on urine electrolyte assessment. Ten healthy young adults (24±4 yr; 1.75 m; 68.0 kg) provided fresh urine samples. Each sample was analyzed for urine electrolytes immediately then stored in each temperature (22°C, 4°C, -20°C, and -80°C), separately for 1, 2, and 7 days, respectively. Urine electrolytes were stable at 22°C, for 1 day (p>0.05) and at 4°C up to 7 days (p > 0.05). At -20 and -80°C, urine electrolytes were stable after 1, 2, and 7 days (p > 0.05). These data reflect the stability of urine electrolytes when stored in various environments for different amounts of time. These data are important for clinical diagnostics and the results that are shipped or housed until processing.