Biotyper sample preparation

Quick summary

  1. You grow microorganisms
  2. You pick up a clean target plate at the Core Facility
  3. You apply the microorganisms and the standard to the target plate, bring the target to us
  4. We analyze your samples and email you the results.

Supplies and protocols

MALDI Biotyper supplies and procedures

To order consumables from Bruker, please visit Bruker website.

Biotyper sample preparation guidelines

Samples for Biotyping can be submitted by appointment only because the proteins in the samples are prone to degradation and must be analyzed as quickly as possible. Please email or call at least one day ahead of preparing the samples to confirm that the instrument and the operator will be available when your plate is ready.

In addition to the list of supplies and basic protocols for Biotyper provided at the top of this page, the Biotyper manual in pdf format is available upon request. The Facility does not provide bacterial test standard (BTS) but we usually have some of the supplies on the list, please check with us. Tatiana can show you how to prepare the samples if you are not confident  doing it on your own.

To expedite your analysis, please fill out the Excel Sample ID Template with your sample names exactly as shown. All missing or incorrectly filled sample names will be replaced by the analysis date and your initials. You are responsible for keeping a record of your sample positions. The Excel file with the sample IDs must be emailed to Tatiana. Please attach any other information as separate files or documents.

Tips for successful microorganism identification

It is very important to exactly follow the procedure and use only the fresh, specified-grade reagents and solutions. MALDI is a competitive ionization process and is very sensitive to contaminants commonly present in histology-grade solvents and low-purity chemicals.

More is not better. A correct ratio of matrix to analyte is critical and achieved by following the procedure exactly.

Tube extraction (formic acid extraction) procedure requires extra few minutes of the prep time but yields much better results than the direct transfer procedure. Direct transfer procedure requires practice and is only applicable to non-spore-forming microorganisms. We recommend following the tube extraction procedure for all samples.

The Biotyper does not work well with mixed cultures. If there is small percentage of contaminating microorganism, the technique might still work, but this would be an exception rather than a rule. For best results, cultures should be pure.

If you have any questions or suggestions or would like to discuss your project details, please email or call Tatiana.

Shipping the target plates

Target plates can be shipped overnight on wet ice packs. To protect the sample spots, place the target plate facing down into its original box. You can tape the target to the molded insert inside the box, so it does not get dislodged during shipping.