Identification of Gram-Positive Cocci by Matrix-Assisted Laser Desorption Ionization–Time of Flight Mass Spectrometry (CAT#: STEM-ST-0316-LJX)

In a very small area and a very short time interval (ns order of magnitude), the laser delivers high-intensity pulse energy to the sample under test, causing it to desorption and ionize instantaneously without thermal decomposition. MALDI is a mass spectrometry ionization method for direct evaporation and ionization of non-volatile samples.

For measuring the molecular weight of biological macromolecules, such as the molecular weight distribution of peptides, proteins, nucleic acids, polymers and oligomer analysis.

1. Mix the sample with the appropriate matrix material and load it onto the metal plate.
2. Pulsed laser light is used to irradiate the sample and trigger ablation and desorption of the sample and matrix materials.
3. Analyte molecules are ionized by protonation or deprotonation in the thermal plume of the ablated gas and are then accelerated to a mass analyzer for analysis.

• Sample Type:
Gram-positive cocci

1. During shutdown, if the nitrogen is not turned off, the pressure should be properly lowered to avoid moisture.
2. Keep an eye on instrument drift during manual measurement. If there is drift, the instrument needs to be calibrated with standard peptide or standard protein.