ultraviolet spectrophotometry Spectrophotometry, Ultraviolet 56 article 54 chemistry 46 priority journal 22 unclassified drug 22 mass spectrometry 20 high performance liquid chromatography 18 infrared spectroscopy 16 Article 14 chemical structure 14 controlled study 14 methodology 14 photochemistry 14 water 14 Chromatography, High Pressure Liquid 12 Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization 12 pH 12 thin layer chromatography 12 Animals 10 Kinetics 10 Magnetic Resonance Spectroscopy 10 Mass spectrometry 10 Oxidation-Reduction 10 Solutions 10 Spectroscopy, Fourier Transform Infrared 10 electrospray mass spectrometry 10 kinetics 10 metabolism 10 oxidation reduction reaction 10