Cleaning Endoscopes with Enzyme Cleaner

Q. What are the guidelines for cleaning endoscopes when soaking the instrument in an enzyme cleaner? I have heard the enzyme can become inactive. How and why does that happen, and how can I be sure my detergent is still working?

A. Cleaning endoscopes can certainly be quite a challenge.  Your set up, endoscope type, and washing conditions can all have an effect.  We at Alconox, Inc. have a great deal of experience and can create customized procedures for your needs.  And as always, we are happy to assist you as needed.  Just let us know!

Regarding your specific question, on the market, there are liquid concentrates and powdered enzyme cleaners. Liquid concentrate enzyme cleaners are thought to be easier to handle, dissolve and dose.

The issue with liquid enzyme cleaners is that the enzyme is active in the liquid state.  As such, the protein enzyme may eat itself (autocatalysis) or otherwise degrade and lose activity over time (because, after all, it is active and enzymes are made of protein).  The detergent formulator may use excess enzyme and more expensive ingredients to stabilize the enzyme in order to get any kind of useful shelf life.  Extra care in the storage and handling conditions with the shelf life and monitoring may be required with liquid enzyme cleaners as well.

Powdered enzymatic cleaners such as Tergazyme® Enzyme-Active Powdered Detergent are highly stable in the powder state and only become active when dissolved in solution. This also results in a substantially more economical and reliable cleaner.  The shelf life of Tergazyme powder in a sealed or tightly closed container is two years.  (Please note that due to the above reason, we recommend usage of the Tergazyme detergent solution within 8 hours to ensure highest proteolytic activity.)

This is a general abbreviated procedure when using Tergazyme detergent:

  1. create a warm (< 130F / 55C to avoid enzyme degradation) 3% Tergazyme solution
  2. soak and actuate (to ensure complete surface contact) endoscope instrument for 20 minutes
  3. thorough rinsing with DI or similar quality water

Again, we are happy to discuss the details further as this cleaning procedure is a highly critical step.  Disinfection/sanitization/sterilization alone, without a prior thoroughly cleaned endoscope, may lead to contamination events.

To request Tergazyme enzymatic cleaner or any Alconox, Inc. detergents for free, please complete the questionnaire at Get Sample.  For more information about any one of our Alconox, Inc. detergents, consult the technical bulletin for each product. Or click here to access each of our detergent’s  Safety Data Sheets.

Do you have a critical cleaning question, about cleaning endoscopes, or any topic, for the experts at Alconox, Inc.?  Search TechNotes to see if it’s been answered before or Ask Alconox.

Contact us any time: cleaning@alconox.com