Basic Rules for Handling Biocatalysts

Like with chemical catalysts, a few guidelines should be observed with biocatalysts to preserve activity and to handle them safely. Depending on the formulation -liquid, lyophilized, spray-dried, immobilized - different rules apply. Enzymes are often perceived as unstable and delicate entities, however, when treated in the right way, they can be as sturdy as almost any chemical catalyst. For optimal stability, enzyme preparations are usually stored best in their original commercial form, either as lyophilizate, spray-dried powder or (stabilized) liquid. 

Direct contact with enzymes should be avoided. This is particularly important with respect to the inhalation of aerosols (from liquid formulations) or protein dust from lyophilized or spray-dried protein preparations. Depending on the person, the tendency to develop allergies (itching, red stains) can be very different. However, the development of serious health problems due to contact with cell-free protein formulations is extremely unlikely. 

Occasionally, the use of an enzyme inhibitor may be necessary to suppress undesired side reactions due to further metabolism. You should be aware that the majority of them (in particular serine hydrolase inhibitors) are extremely toxic and must be handled with the utmost care, like (for example) osmium tetraoxide. 

The following processes lead to rapid enzyme deactivation and thus should be 

Liquids. Liquid enzyme formulations usually contain a significant amount of stabilizing agents, such as carbohydrates, polyols and inactive (filler) proteins. In addition, side-products from the fermentation may be present. In general, they tend to stabilise enzymes and thus their removal (e.g., by dialysis) is not recommended. The same apphes to dilution, as concentrated protein solutions are usually more stable. Liquid formulations should be stored in the cold (0 to +4°C), but avoid freezing If long-term storage is required, two options are possible (if in doubt, test both methods on a sample first and check for any loss of activity)  

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