Guanidine phosphate is primarily used in the field of molecular biology as a protein denaturant. It is effective in breaking down protein structures, making it valuable for studying protein folding and unfolding mechanisms. Additionally, it is utilized in the purification of nucleic acids, where it helps in the isolation of DNA and RNA by disrupting cell membranes and inactivating nucleases. In biochemical research, guanidine phosphate is also employed in the preparation of samples for electrophoresis and chromatography, ensuring accurate analysis of biomolecules. Its strong chaotropic properties make it a key reagent in various laboratory protocols involving protein and nucleic acid manipulation.