FIELD: microbiology.
SUBSTANCE: disclosed is a sample preparation method for accelerated identification of microorganisms from positive hematological cultures, comprising collecting 5 ml of a culture medium with blood from a flask with a positive blood culture into a vacuum test tube with a separating gel, centrifuging for 12 minutes at 1,000 g, removing the supernatant without affecting the layer of cell detritus with microorganisms on the surface of the gel. 1.5 ml of sterile saline is added, the sediment is resuspended, centrifuged for 3 minutes at 100 g; 700 mcl of the supernatant is transferred into an Eppendorph test tube, centrifuged for 2 minutes at 10,000 g; the supernatant is removed, 15–25 mcl of 70 % formic acid is added to the sediment, the mixture is stirred and 15–25 mcl of acetonitrile is added, the mixture is stirred and centrifuged for 2 minutes at 10,000 g. On a target for a mass spectrometer, 1 mcl of the supernatant is applied on 2 points and a precipitate is applied on 2 additional points, dried at room temperature and coated with a matrix of α-Cyano-4-hydroxycirmamicacid; matrix drying is followed by identification on a MALDI ToF mass spectrometer.
EFFECT: invention provides identification of microorganisms without isolation of their pure culture.
1 cl, 1 tbl, 1 ex
