The 4.1M Ammonium Sulfate Solution is widely utilized in biochemistry and molecular biology for precipitation and fractionation of proteins, hydrophobic interaction chromatography, and purification of antibodies. This solution is also commonly used in applications such as long PCR, second-strand cDNA synthesis, and HPLC analysis of phospholipids. The use of high concentrations of ammonium sulfate has been shown to inhibit microbial growth and maintain the protein in a folded state.