<qa>  What is the DNA amount measured by microfluorimetry?We characterize sputum composition of patients with pulmonary exacerbations. Using gel electrophoresis and dot-blot with specific antibodies we will analyze MUC5AC and MUC5B mucins. DNA amount will be measured by microfluorimetry. With the laser scanning confocal microscopy the mucin-DNA-network will be evaluated. 