Unlock Exclusive Discounts & Flash Sales! Click Here to Join the Deals on Every Wednesday!

Analysis of bone collagen by matrix-assisted laser desorption/ionisation time-of-flight mass spectrometry (CAT#: STEM-ST-0310-LJX)

Introduction

Species identification of fragmentary bone, such as in rendered meat and bone meal or from archaeological sites, is often difficult in the absence of clear morphological markers. Here we present a robust method of analysing genus-specific collagen peptides by mass spectrometry simply by using solid-phase extraction (a C18 ZipTip®) for peptide purification, rather than liquid chromatography/mass spectrometry (LC/MS). Analysis of the collagen from 32 different mammal species identified a total of 92 peptide markers that could be used for species identification, for example, in processed food and animal feed. A set of ancient (>100 ka@10°C) bone samples was also analysed to show that the proposed method has applications to archaeological bone identification.




Principle

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.

Applications

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

Procedure

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.

Materials

• Sample Type:
Bone collagen

Notes

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.