Microbial Identification

MBT Lipid Xtract Kit

Rapid colistin resistance detection on MALDI Biotyper® sirius

MBT Lipid Xtract Kit (RUO)

The MBT Lipid Xtract Kit facilitates efficient sample preparation for analysis of microbial lipids, enabling fast resistance detection based on MALDI-TOF analysis of Lipid A modifications, on the MALDI Biotyper® sirius, using negative ion mode.


Exploring lipidomics for resistance detection

Resistance of gram-negative bacteria to colistin, one of our last resort antibiotics, is based on modifications of the bacterial lipopolysaccharides (LPS). Modifications to Lipid A lead to charge repulsion effects of colistin, resulting in resistance of the bacteria.

Typically, analysis of lipids by MALDI-TOF is performed in the negative ion mode, which is available on the MALDI Biotyper® sirius systems.

Modifications to the Lipid A molecules include, amongst others, phosphoethanolamine (pEtN) addition to the core and Lipid A regions, and 4-amino-4-deoxy-L-arabinose (L-Ara4N) addition to the core and lipid A regions. The corresponding Lipid A mass shifts caused by these modifications can be detected easily by the MALDI Biotyper® sirius after performing the sample extraction protocol provided by the MBT Lipid Xtract Kit.

Fast and easy extraction of Lipid A and its derivatives

Only 15 minutes are needed for sample preparation of Lipid A and its modifications, by means of the MBT Lipid Xtract Kit. It takes only a small colony, which undergoes lysis, and is subsequently mixed with Lipid Xtract matrix after a washing step. This mixture can be directly transferred to a MBT Biotarget 96 for MALDI-TOF analysis. Using the negative ion mode on a MALDI Biotyper® sirius system, lipid spectra are acquired in the lower mass range.

Lipid A spectra: what do they tell us

The excellent extraction efficiency of the MBT Lipid Xtract kit results in high-quality spectra, enabling a broad range of MALDI-TOF applications based on Lipid A analysis.

Inspection of the spectra can reveal the origin of colistin resistance, as phosphoethanolamine (pEtN) addition to Lipid A strongly indicates a plasmid encoded resistance, whereas a 4-amino-4-deoxy-L-arabinose (L-Ara4N) addition points to chromosomal encoded resistance.

Results at a glance with the MBT LipidART Module

This dedicated software module requires only a few mouse clicks to extract information from the MALDI-TOF spectra, and delivers easily interpretable answers, indicating whether the resistance is based on chromosomal or plasmid coded modifications.

As the results are available after only 30 minutes starting from a colony, this test enables testing many samples in a short time.



For Research Use Only. Not for use in clinical diagnostic procedures.

Please contact your local representative for availability in your country.