Use of an alcohol-salt buffer wash for the efficient recovery of mycobacteria and mycobacterial DNA from respiratory sediment

摘要

The present invention relates to methods for concentrating bacteria from a viscous biological sample. The methods involve adding to the sample a water-soluble, density-lowering agent having a density of .7 to .9 g/ml and a boiling point greater than 50 DEG C. The invention also relates to methods for concentrating bacteria and free bacterial nucleic acids from a biological sample that involve mixing with the sample a density-lowering agent and a monovalent salt.