BlighDyerprotokollen

BlighDyerprotokollen, commonly known as the Bligh and Dyer lipid extraction method, is a standard procedure for isolating total lipids from biological samples. Developed and published in 1959, it uses a chloroform–methanol–water system to partition lipids into an organic phase. It is widely employed in biochemistry and lipidomics for tissues, cells, and body fluids.

Principle: The method relies on partitioning lipids into chloroform. A sample is homogenized in methanol and chloroform to form a single-phase mixture; water is then added to yield a two-phase system. In the final mixture, lipids reside in the chloroform (organic) phase, while nonlipid contaminants remain in the methanol–water phase. The typical final solvent ratio is roughly chloroform:methanol:water 1:1:0.9.

Procedure (high level): The biological material is homogenized in a methanol–chloroform mixture, then water is added to provoke phase separation. After centrifugation, the lower organic layer containing lipids is collected. The organic phase is often washed with a saline or methanol–water solution, re-centrifuged, and the solvent evaporated to yield crude lipids for downstream analyses such as thin-layer chromatography, gas chromatography, or mass spectrometry.

Variations and scope: The method has several variants, including the Folch protocol and later adaptations to accommodate different sample types and lipid classes. While efficient and widely adopted, the procedure uses toxic solvents and can exhibit differential extraction efficiencies for certain lipid subclasses.