“Rinse three times.” The standard rule of scientific dishwashing which will inevitably become how you wash dishes at home. What took me a while (perhaps too long) to understand was just how many considerations there are when it comes to dishwashing.

The lesson: a dishwashing plan should be a component of your experimental design.

Far too often, data can be “noisy” or “messy” because of a lack of understanding in how our scientific dishes need to be cleaned before and after our experiments.

Let’s start simple and stay within the realm of “rinse three times” by first asking what are we rinsing off? There are four general types of detergents: anionic, cationic, non-ionic, and zwitterionic (no, that last word is not a typo). The decision of which is based on proteins – use an ionic if you want to disrupt and denature proteins, or if you need to preserve protein structure and function, use a non-ionic or zwitterionic.

When we have dishes that have the potential to be harbouring bacteria, viruses, fungi, and spores – an autoclave sterilization will decontaminate those biohazards. (if using plastics, be mindful that it is autoclave safe, otherwise you’ll have quite a mess on your hands!)

Proteins and biologicals addressed, what about oils?

When water-based detergents just aren’t enough (i.e., you have oils or grease residues), you need a solvent rinse. Choose wisely as not all are compatible – acetone and ethanol are common choices.

Now we’ve got the bulk of the “stuff” off – but scientific analyses can be sensitive. Trace metal analysis and dissolved organic carbon are two examples where washing dishes at the sink are not enough.

Acid washing is a great tool to remove inorganic residues like mineral build up or adhered metals.

High heat (500 C) is also a useful tool for the cleaning of glassware, especially for use in carbon-based analyses.

How clean your dishes are will determine how clean your data will be.

A bonus tip, if you read to the bottom of this: rumor has it, a Instant Pot on the sterlize setting works as a portable autoclave in a pinch.