Figure 1From: Comparison of exhaled breath condensate pH using two commercially available devices in healthy controls, asthma and COPD patients Effect of duration of degasification on fresh and frozen EBC samples. EBC samples collected by RTube were obtained from 5 healthy controls, and either used fresh or after storage at -20°C (frozen). Prior to pH analysis, EBC samples were de-aerated using argon gas for various periods of time. Results show mean ± SD.Back to article page