Figure 2. Stability of Proteins in Norgen's Urine Preservative. Urine samples were collected from numerous healthy donors and pooled, and then the urine was aliquoted into 5 mL aliquots in Norgen's Urine Collection and Preservation Tubes (5 cc) (Cat# 18116). The preserved urine was stored at -20°C, 4°C and room temperature for up to 24 months. Urine proteins were then subsequently isolated at time 0, 1 month, 2 month, 4 month, 8 month, 12 month, 16 month, 20 month and 24 month from the preserved urine using Norgen's Urine Protein Concentration Kit (Cat# 17400).To test the purified urine proteins, the BioRad protein assay, based on the Bradford assay, was used to determine the concentrations of the total urinary proteins. In this assay, the standard curve was constructed using known amounts of bovine serum albumin (BSA) (NEB, Pickering, ON, Canada). The concentrations of protein samples were determined based on this standard curve of known protein concentration. The absorbance (Abs) readings were taken at 595 nm. As it can be seen, all the preserved urine samples stored at all 3 temperatures yielded similar total protein yield with no significant change from 0 months to 24 months. Conclusion: Urine proteins can be stored in Norgens Urine Preservative for up to 2 years at room temperature, -20C and 4C without any change in quantity of proteins.

Figure 3. Stability of DNA in Norgen's Urine Preservative. Urine samples were collected from numerous healthy donors and pooled, and then the urine was aliquoted into 5 mL aliquots in Norgen's Urine Collection and Preservation Tubes (5 cc) (Cat# 18116). The preserved urine was stored at -20°C, 4°C and room temperature for up to 48 months. Urine DNA was subsequently isolated at time 0, 1 month, 2 months, 4 months, 8 months, 12 months, 16 months, 20 months and 24 months from the preserved urine using Norgen's Urine DNA Isolation Kit (Slurry Format) (Cat# 48800). To test the integrity of the purified DNA, 3 µL of each elution was used in a 20 µL Taqman PCR reaction run on a CFX96 Touch Real-Time PCR Detection System (Bio-Rad) using Norgens 2X PCR Master Mix with 5s rRNA primers. As it can be seen, all the DNA samples were successfully amplified. Furthermore, the quality of the concentrated and preserved urine DNA stored at all 3 temperatures did not significantly change from 0 months to 24 months, as indicated by the fact that the Ct value remained consistent.