| Abstract: | Urine wetting properties may influence the design and performance of catheters, urinalysis instruments, and lab-on-a-chip technologies. In this study the advancing contact angle adv of urine on several materials is characterized. Material type and surface tension have a significant effect on adv, while pretreatment and aging do not. Mean urine adv are between ≈78° and ≈89° on hydrophilic surfaces, and up to over ≈105° on hydrophobic surfaces. Expected urine contact angles will decrease from the DI water contact angles by on average 10°, and up to 20°, while urine surface tension will be lower than DI water by 12.12 mN/m and 18.53 mN/m. A unit change (mN/m) in surface tension results in a 0.75° change in adv. These results indicate that systems attempting to exploit urine wetting must account for highly variable conditions. |
