VITEK MS Collaborative Study Outline - eBook
Proceed likewise for a second sample, etc. 1 After about five minutes check for crystal formation on the spots. Inexperienced users may find using a 2 magnifying glass helpful. Measurement will succeed only if matrix crystals have become visible as a 3 yellowish film. Ideally, most of the spot’s surface will be coated with crystals.
4 5
6 When the VITEK MS‐DS target slides have been prepared, they must be tested within 48 hours. 7 Prepared slides should be stored at room temperature until they are tested. 10 The preparation of yeast samples differed from the standard procedure in that VITEK MS‐FA (formic acid 11 treatment) was applied to the organism on the VITEK MS‐DS prior to adding VITEK MS‐CHCA. Care was 12 taken not to add VITEK MS‐CHCA until the VITEK MS‐FA was completely dry, usually after 1 ‐ 3 minutes. 13 The sample was applied to the VITEK MS‐DS as in the standard procedure. Then 0.5 μl of VITEK MS‐FA 14 was added to the sample, using a new pipette tip for each sample. Enough time was allowed for 15 evaporation of VITEK MS‐FA before adding VITEK MS‐CHCA. The cell suspension formed a thin, moist 16 film on the target position. This usually took between 1 ‐ 3 minutes. Once the slide was completely dry, 17 1.0 μl of the VITEK MS‐CHCA was added to each sample as in the standard procedure. 18 Follow VITEK MS package insert instructions for running the instrument. 19 Note: The E. coli calibrator was not treated with VITEK MS‐FA. 20 8 9 Sample Preparation for Yeast
21 22
Interpretation and Test Result Report 23 The VITEK MS system identified blind‐coded organisms (previously characterized) by comparing the 24 characteristics of the obtained spectrum to the VITEK MS knowledge base. A percent agreement 25 calculation was performed. 26 A quantitative value, the confidence value, was calculated and expressed the similarity between the 27
Page 5 of 58
Made with FlippingBook Online newsletter