How to quickly obtain data on the stability of protein formulations
Proteins are essential for life. They are responsible for structure and functioning of living cells, they are elements of growth and repair, and they help us fight infections. We find them in our food, (biological) drugs, cosmetics and others.
In solution, proteins are prone to associate. This can lead to protein crystallization, to the formation of amorphous aggregates, or to the liquid-liquid phase separation where the two liquid phases differ in the concentration of the protein. Instability of protein solutions can be both desired (e.g. protein isolation, crystallization for structure determination) and undesired (e.g. causing diseases such as cataract of the eye lens or Alzheimer‘s disease; short shelf-life of biological drugs, etc).
Phase transition in protein formulations may appear due to many factors: type of the protein and its concentration, pH and temperature of the solution, type and amount of additives (e.g. salts, sugars).
This application note discusses how to quickly obtain data on the stability of protein formulations, made possible with the use of the real time digital camera of the Crystalline instrument. It includes a case study on the stability of iysozyme formulations.