Comparison of three methods for protein measurement: application to bronchoalveolar lavage fluids.

The protein contents of bronchoalveolar lavage fluids from normal subjects and patients were estimated by three methods: LOWRY's assay, Coomassie blue method and the automatic laser nephelometric assay. The assays were carried out with native fluids and human serumalbumin as the standard. The lowest values were usually obtained with the dye-binding method. The best correlation coefficients between the assays were obtained from the pulmonary lavage of patients.