Citrate buffer is widely used in molecular biology and biochemistry for maintaining stable pH levels during various experimental procedures. It is particularly effective in antigen retrieval techniques for immunohistochemistry, where it helps unmask epitopes in tissue samples, enhancing antibody binding. In electrophoresis, citrate buffer is employed to stabilize the pH of the gel, ensuring consistent separation of nucleic acids or proteins. Additionally, it is utilized in enzyme assays to provide an optimal pH environment for enzyme activity. Citrate buffer also plays a role in pharmaceutical formulations, where it acts as a buffering agent to maintain the stability and efficacy of drugs. Its ability to chelate metal ions makes it useful in preventing oxidation in certain solutions, extending the shelf life of sensitive compounds.