Development of a Sensitive High-Resolution Mass Spectrometry Approach for Urea Nitrogen Quantitation in Small Volumes of Bronchoalveolar Lavage Fluid (BALF) - Ulmer, Candice Z.; Smith, Bianca; Thonkulpitak, Janet; Hardin, Joshua; Danilenko, Uliana; Frame, Tunde; Cheng, Po-Yung; Vesper, Hubert W. (Journal of the American Society for Mass Spectrometry, 2020)