Discover, Mars 6, Discover SP-D

Protein hydrolysis is a tried and tested digestion procedure from the 1950s (Stein and Moore) of proteins and peptides for analyzing amino acids. Amino acid analysis (AAA) is used to quantify the individual amino acids of the respective sample and is a prerequisite for identifying the amino acid sequence of the protein/peptide.

The hydrolysis step is typically carried out at a temperature of 110 °C with a 6N hydrochloric acid and cleaves all bonds between the individual amino acids of the protein/peptide to be analyzed. This step is very time-consuming and typically takes 20 to 24 hours. In addition, inert reaction conditions are created so that the oxygen in the air cannot react with the amino acids. This hydrolysis step can be carried out in the gas phase to achieve low detection limits, especially for small sample quantities (500 picomoles/100 µg). Larger sample quantities are often processed in direct contact with hydrochloric acid (liquid phase hydrolysis).

With the help of microwave-assisted protein hydrolysis, liquid hydrolysis in the Mars 6 or Discover SP-D as well as gas phase hydrolysis in the Discover can be carried out quickly and gently.

Hydrolysis technologies

Gas-phase hydrolysis

With the help of microwave technology, a number of advantages can be achieved in this established process:

1. The time saved by using microwave technology is also enormous in protein hydrolysis. Instead of running the decomposition reactions overnight, the microwave can achieve comparable results in just 15 minutes.
2. The digestion efficiency is increased. Especially with hydrophobic proteins, digestion under microwave activation has been significantly improved.
3. Up to 10 standard HPLC autosampler vials (100 - 300 µl) can be used in one run. Every 15 min. 10 samples can be hydrolyzed again and thus an extremely high sample throughput can be realized.

Liquid hydrolysis

Protein hydrolysis is used to cleave all peptide compounds in a protein chain. The resulting free amino acids are quantified using amino acid analysis. The proteins are isolated from living organisms (biochemistry, biotechnology...), from food and animal feed (dairies, meat and sausage products, breweries and the beverage industry) or from blood and urine for diagnostic purposes. Protein hydrolysis with microwave support in the MARS 6 and Discover allows fast and reproducible cleavage of peptide or protein chains. The hydrolysis time can be reduced from several hours to minutes. In addition, the equipment required for microwave hydrolysis is less than for the classic technique.