The Preparation of Parotid Fluid Protein-Free Filtrates

摘要

The effectiveness of nine methods for precipitating protein in parotid fluid was investigated. Measurement was made of total nitrogen concentration and total protein concentration on the protein-free filtrates. Nitrogen measurements were performed by a semi-micro-Kjeldahl procedure and the proteins were measured by the Lowry method. Three methods were found to remove all of the protein: (1) An acetic acid in acetone method. (2) Somogyi's copper sulfate method. (3) Somogyi's barium hydroxide method. The two Somogyi methods removed uric acid in addition to the protein. (Author)