High-performance liquid chromatography method development and validation for simultaneous determination of five model compounds, antipyrine, metoprolol, ke-toprofen, furosemide and phenol red, as a tool for the standardization of rat in situ intestinal permeability studies using timed wavelength detection - Chawla, S; Ghosh, S; Sihorkar, V; Nellore, R; Kumar, TR; Srinivas, NR (Biomed Chromatogr., 2006)