Spectra quality is one key factor for a successful identification. Several factors can contribute to low-quality spectra: 

1. Sample Preparation Issues:

Poor Sample Preparation: Inadequate sample preparation can lead to low sensitivity, poor resolution, and poor reproducibility of the spectra. There is unfortunately not one universal sample preparation protocol. Depending of the germ and the desired degree of differentiation (genus, species, subspecies, lineage) corresponding sample preparation and analysis conditions must be applied.  

Improper Matrix-to-Analyte Ratio: An incorrect ratio of matrix substance to analyte can degrade ion generation, affecting spectral quality. Often too much sample material is used, less is more! 

Use of Low-Purity Chemicals: Using chemicals that are not of high purity can lead to low quality spectra. 

2. Instrumental Factors:

 Lack of Calibration: Frequent calibration of the MALDI-TOF MS device is essential for maintaining high spectral quality. 

Instrument Sensitivity and Reproducibility: Variability in measurement precision and sensitivity can affect spectral quality. Regular instrument service and regular testing and adjustment of the sensitivity of the analysis method (laser and detector) must be carried out 

3. Biological Factors:

Age of Bacterial Colonies: Older bacterial colonies may not provide as clear a spectral profile as younger colonies. 

Amount of biomass: Insufficient or excessive biomass or inefficient cell lysis can lead to poor quality spectra. 

Choice of sample preparation protocol: Depending on the type of germ and the desired degree of differentiation (genus, species, subspecies, lineage) corresponding sample preparation and analysis conditions must be applied. 

4.  Analytical Conditions:

Beside the afore mentioned points, for some species the use of sinapic acid instead of HCCA matrix is required. This leads to richer spectra especially in the upper mass range (10-20 kDa). This is the case for some close related species like Salmonella, Bacillus cereus group species or for subtyping purposes beyond the species level (subspecies, Lineages). For the use of sinapic acid as matrix a corresponding acquisition method has to be set up on your MALDI TOF MS machine.  For support please contact your local vendor or the staff from Mabriteccentral. 

Sample Preparation: The amount of bacterial colony material added to the target plate and the age of the bacterial colony can significantly impact spectral quality. Inadequate or excessive sample material, as well as older colonies, can lead to suboptimal results. Variations in sample preparation protocols, measurement conditions and matrix used (HCCA or Sinapicacid) can affect the quality of the spectra. Different bacterial taxa may require specific sample preparations for optimal spectral quality. There is unfortunately not one universal sample preparation protocol. Depending of the germ and the desired degree of differentiation (genus, species, subspecies, lineage) corresponding sample preparation and analysis conditions must be applied. 

We distinguish three different types of sample preparation protocols: 

The “Smear” method:

In the classic smearing method, a small amount of sample material is applied directly to a spot on a target plate and overlaid with 1 µl HCCA or Sinapicacid matrix. One variant, especially for gram-positive germs, involves an additional step. Coate the smeared sample with 1 µl formic acid (25%) and dry at room temperature. The sample is then overlaid with 1 µl HCCA or Sinapicacid matrix.              All samples must be completely dry before analysis. Works well for most of the gram-negative germs especially Enterobacteriaceae which occur often in clinical settings. However, some close related species are still difficult to discriminate and the use of Sinapicacid instead of HCCA as matrix might be indicated.  

The ”Bruker Extraction” method:

Collect a loopful of bacterial colonies and suspend them in 300 μL of distilled water in a microcentrifuge tube. Add 900 μL of ethanol to the suspension, mix well, and centrifuge at 17,000 × g for 2 minutes. Discard the supernatant and allow the pellet to air dry. Resuspend the dried pellet in 50 μL of 70% formic acid and mix thoroughly. Add an equal volume (50 μL) of acetonitrile to the suspension and mix again. Centrifuge the mixture at 17,000 × g for 2 minutes. Transfer 1 μL of the supernatant onto a spot on the MALDI target plate. Allow it to air dry at room temperature. Overlay the dried sample spot with 1 µl HCCA or Sinapicacid matrix.         All samples must be completely dry before analysis. 

The “Bead Beating” method:

Collect 1-3 loops of bacterial colonies suspend them in 1 ml of TMA washing buffer and centrifuge at 17,000 × g for 2 minutes. Discard supernatant and repeat wash step 1-2 times. Suspend pellet in 200 μL TMA buffer and glass beads 0.1 mm. The samples is then disrupted in a homogenizer or bead beater.  All samples must be completely dry before analysis. 

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MabrTax means «mabritec Taxonomy» and describes a genomospecies (e.g. https://help.ezbiocloud.net/genomospecies/).

Our database phylogeny is based on whole genome comparisons (ANI). Species that cannot be assigned to a type-strain are then named MabrTax.

You can export your results in two formats:

• CSV Export:
  Navigate to the results page.
  Click on the “CSV export” button.
  The CSV file will download to your device, which you can open with any spreadsheet application like Excel or Google Sheets.
• PDF Export:
  Navigate to the results page.
  Click on the “PDF export” button.
  The PDF file will download to your device, ready to be printed or shared.

You can upload a variety of file types to Mabritec Central, including but not limited to standard mass spectrometry data formats such as .mzML, .txt. We also support .zip for Bruker experiments. If you have any specific file format inquiries, please contact our support team for further assistance.

• Bruker Maldi Biotyper
• Biomérieux VITEK MS
• Shimadzu MALDI⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠-⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠8020
• Shimadzu MALDI⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠-⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠8030

Yes, our database is compatible with both formic acid matrix and sinapinic acid matrix. These matrices are commonly used in mass spectrometry applications, and our database has been optimized to support data generated using both types, ensuring accurate results and seamless integration with your analytical processes.

With mabriteccentral, there are no limits! You can upload and process an unlimited number of spectra, ensuring you have the flexibility to manage as many samples as you need, whenever you need it.

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Invoices must be payed within 30 days via a bank transfer.