Questions and Answers
What can the MALDI-UP catalogue be used for?
In the MALDI-UP catalogue, sample materials, i.e. MALDI single spectra and database entries, are listed. However, not the spectra or database entries themselves, but the metadata of the measurements and sample materials are presented in the form of an overview list. The measurement files are kept by the creators and are not uploaded to MALDI-UP.
If there is an interest in a specific material, such as a single spectrum or database entry, the creators can be contacted via the contact list and asked to exchange spectra. The goal of the MALDI-UP catalogue is to support a network formation through the mutual information exchange between MALDI users and to expand the application possibilities for the users.
Is the use of MALDI-UP free of charge?
Yes, MALDI-UP is designed to facilitate open scientific exchange among users. What is listed in MALDI-UP is not intended to be commercial. An instruction for the use of the MALDI-UP list can be found on the website as “Instructions” under the catalogue tab.
Who is operating MALDI-UP?
MALDI-UP was started in 2015 by MALDI users from the Chemical and Investigation Agencies (CVUA) in Baden-Wuerttemberg and the Hessian State Laboratory. The website is hosted as a subdomain of ua-bw.de under the terms specified there. Maintenance and editing are currently carried out by employees of the Chemisches und Veterinäruntersuchungsamt Stuttgart (CVUAS), Germany.
Is MALDI-UP limited to microorganisms such as bacteria?
No. Microorganisms do represent a large proportion of the reference and validation spectra due to the previous interests of the users. However, the platform is explicitly designed to support a wide range of applications.
Reference spectra for meat, fish, dairy products, insects, crustaceans, fungi, and plants, among others, can be found in addition to microorganisms. These are used to identify animal species, for example. More themes and more list entries for exchange are welcome.
How to search in the MALDI-UP catalogue?
There are different sheets in the MALDI-UP catalogue (Excel file), in which the available information is structured:
- Isolates - Materials: data on sample materials used, such as isolates, animal or plant materials, e.g. genus, species, name verification.
- Database Entries: Data on measurements of database entries (MSPs), e.g. sample preparation method, used matrix, number of spectra in the entry.
- Single Spectra: Data on measurements of single spectra, e.g. sample preparation method, used matrix, date of measurement.
The filter function allows you to narrow down these tables step by step so that you can search for specific topics. The search function, accessed by pressing [CTRL] and [F], is also useful. Other sheets include a Contact list, Literature references and a History of the MALDI-UP catalogue.
How to request measurement files of single spectra or database entries?
The institution responsible for the respective row is named in the column "user responsible for the row" in the tables of single spectra and database entries. The contact persons’ email addresses can be found in the Contact sheet.
Tip: Include the keyword ’MALDI-UP’ in the subject line of your email.
What information can I find in the "Isolates - Materials" sheet?
In the sheet Isolates - Materials, the metadata for all isolates or sample materials listed in the catalogue are compiled uniformly.
Under the column "isolate / material owner / example of public collection" // "Isolat Besitzer" is indicated where materials can be requested for exchange purposes. For bacterial isolates from public collections, an exemplary source of supply is given.
Are there any spectra that can be downloaded directly?
Some spectra are freely available on the Internet and can be downloaded under the conditions specified by the sources. In the MALDI-UP catalogue, the availability of spectra is indicated in columns A to E in the "Database Entries" and "Single Spectra" sheets. By setting the filter, the "Free download" spectra can be displayed. The references are given as numbers and can be found with a link in the Literature sheet.
In addition, there are freely available MALDI spectra databases. Some of these databases are linked to under the Tools tab of the website, section "MALDI Databases".
Can I provide feedback on individual spectra or database entries?
You have had a good experience with one or more individual spectra/database entries or you have comments/criticism and would like to give a feedback? Please send an informal email to , mentioning the respective single spectrum or database entry. We will include the feedback anonymously in the MALDI-UP catalogue.
Your exchange partner will surely appreciate receiving those details via CC in the email.
Can I contribute spectra by myself?
Yes. A new database entry or a single validation spectra can be added to the catalogue (in Microsoft Excel) with a specified format. For this you can use the form “New Entries for MALDI-UP”.
As a user, you only provide few personal data who characterize you as the owner of the spectra.
Please send the form to .
If another user is interested in your spectra or data base entries, these personal data of the owner allow them to approach you and request the spectra of you.
Your meta data will undergo an editorial review. Finally, the most recent entries will be included in the catalogue’s next update.
How frequently is the MALDI-UP list updated?
We usually update the MALDI-UP catalogue every four weeks. When there are significant changes, such as a large number of new entries, intermediate updates are also carried out.
I would like to list an event with MALDI contents. How could I?
We maintain a section for events on the MALDI-UP page. The listing is free of charge. Commercial offers and offers from companies will be highlighted as such. Feel free to contact . A publication on the MALDI-UP website will then be subject to editorial decision.