How Dirty Are You? Part 2…Pipet Bulbs…The Answer

Check out the first How Dirty Are You? blog about Parafilm.

The How Dirty Are You? pipet bulb blog showed some interesting data…mainly that I need to clean my pipet bulbs and periodically replace them. I am happy to report that I have changed my pipet bulb twice since and even do some solvent rinses.

The question I posed in the initial blog was about a high intensity peak found when a latex bulb was rinsed with acetonitrile. The question I asked was what type of common additive was responsible for producing such a high signal…

Was it a Dye, Antioxidant or UV Stabilizer?

Some people indicated that they thought it was a phthalate. This is a very good guess based on the numerous times phthalates appear in blank samples, but in this case the compound was identified as butylated hydroxytoluene (BHT).



BHT is an antioxidant compound that is used in everything from rubber to food, pharmaceuticals…even embalming fluid! This stuff is everywhere.

PHOTO: food 2


BHT lotion 1


latex bulb cgram update



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