Total reflection X-ray fluorescence spectroscopy (TXRF) could complement IR and Raman spectroscopy. Spectroscopy, including infrared (IR), Raman, 2D-fluorescence, and total reflection X-ray fluorescence mixed with multivariate knowledge analysis, are sometimes thought-about. When extra intensive fingerprinting or investigative work is required, several strategies may be useful, trusted amino acids manufacturer including chromatography or inductively coupled plasma mass spectrometry (ICP-MS). High- or extremely-high-efficiency liquid chromatography is commonly used within the reverse part mode with aqueous or water-soluble samples.