Categorized | Alcojet, Citrajet, Laboratory

Residue-Free Glassware Cleaner for Lab Washer

Q: I am currently looking for a residue-free glassware cleaner to use in our new lab dishwasher. We would like to make sure that residue is not left behind on our glassware after washing. This is a normal portable dish washer that is typically used in the home. Could you recommend a detergent for us to use?

A: Thanks for your question about a residue-free glassware cleaner for use in a portable home dish washer with a deionized water hook up. We recommend that you use Alcojet® Low Foaming Powdered Detergent, and that you add some Citrajet® Low-Foam Liquid Acid Cleaner/Rinse to the rinse aid compartment.

Use Alcojet detergent to fill the dispenser cup when cleaning.  Of course a portable household washer has some limitations regarding the ability to do an acid rinse cycle that would be a typical feature of a Miele, Lancer, or Labconco lab washer, but by adding Citrajet to the rinse aid dispenser, at least you will get some acid rinsing.

Acid rinsing is very desirable to be sure that any free base forms of APIs are effectively removed. Acid rinsing also controls any scale buildup.  At least your washer has deionized water used in it.

We do not recommend using any Jet Dry or other household rinse aid products in this washer because those products are designed to leave water repelling hydrophobic residues on glassware.

Please be very careful loading the racks with glassware to avoid loading anything that has an upward facing trough or cup such as the underside of a large graduated cylinder loaded upside down.  These cups or troughs will hold enough wash solution to contaminate the rinse water which will then leave water spots on the glassware when it dries.

Unfortunately some household washers have a section of pipe in the sump that holds wash water and contaminates the rinse water, so without using a product like Jet Dry it can be very difficult to get spot free glassware without having the Jet Dry residues.

Alcojet will work perfectly well as the alkaline detergent.  Putting some Citrajet in the rinse aid dispenser will get you a little bit of acid rinsing.  Taking some care in how you orient glassware to make sure it does not trap wash water and using a deionized water rinse will give you the best chance at getting residue free glassware.

If you are doing glassware with lots of free base actives that really need more acid cleaning, then with a household-type lab washer, you can run the cycles through the pre-wash, wash, and then at the beginning of the 1st rinse cycle, you open the door and pour in 2.5 ounces of Citrajet, close the door, and let the rest of the rinsing and cleaning proceed.

You can also consult Lab Washer Guide for more information on labware washing best practices.

To request these 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.

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Contact us any time: cleaning@alconox.com