Used primarily for desalting and buffer exchange in protein and nucleic acid purification. Effective for removing small molecular weight contaminants such as salts, dyes, or labeling agents from larger biomolecules. Commonly applied in gel filtration chromatography where it separates molecules based on size, allowing macromolecules to elute first while retaining small molecules within its matrix. Frequently used as a cleanup step following protein labeling, phosphorylation, or conjugation reactions. Suitable for small-scale preparative work and sample preparation for downstream applications like electrophoresis, mass spectrometry, or HPLC.