Which method is used to analyze molecules based on their mass?

Mass spectrometry is a powerful analytical technique used to determine the mass-to-charge ratio of ions. This method allows scientists to identify and quantify molecules based on their mass. In mass spectrometry, the sample is ionized, and the resultant ions are sorted according to their mass-to-charge ratios. This provides detailed information about the molecular weight, structure, and composition of the analyte.

The importance of using mass spectrometry lies in its sensitivity and accuracy, making it an invaluable tool in various fields including biochemistry, pharmacology, and environmental science. It enables researchers to analyze complex mixtures and identify components at very low concentrations, which is not as effectively accomplished by methods such as gel electrophoresis, Western blotting, or chromatography. These techniques may separate or identify biomolecules but do not focus primarily on analyzing them based on their mass.