Hexane is a quintessential non-polar alkane solvent in biochemistry, prized for its selectivity in extracting hydrophobic lipids and purifying non-polar metabolites from complex biological matrices.

Chemical Properties

n-Hexane (C₆H₁₄, CAS 110-54-3) forms a straight-chain saturated hydrocarbon with weak van der Waals forces, resulting in a low boiling point of 68.5–69.1°C, melting point of −96 to −94°C, and density of 0.655 g/mL. Non-polar (dielectric constant ≈ 1.9), it shows negligible water solubility (9.5 mg/L) but mixes readily with chloroform, ether, and other alkanes, while exhibiting high volatility (vapor pressure 17.6 kPa at 20°C). Laboratory-grade hexane (>95% n-hexane) minimizes branched isomer content to reduce neurotoxicity risks during extraction procedures.

Biochemical Applications

In lipid biochemistry, hexane is widely used for extracting neutral lipids such as triglycerides and sterols from Folch chloroform–methanol phase systems or Soxhlet extraction setups. It enables thin-layer chromatography fractionation of cholesterol esters and fatty acids prior to GC-MS analysis. Hexane is also employed for delipidation of expressed proteins to support crystallization processes and for washing membrane fractions in virology research to isolate enveloped viruses without significantly disrupting glycoprotein structures. In carbohydrate studies, hexane serves to remove non-polar contaminants during polysaccharide purification when combined with polar solvents in biphasic separation systems.