Alginate Worms

Alginate Worms

Create your own worms with alginate! A molecule made up of incredibly long chains of sugar (that is; a polysaccharide) and naturally produced by some types of seaweed.


  • Sodium Alginate

  • Calcium Chloride

  • Warm & Cold Water

  • Food colouring

  • Plastic syringes (without needle)

  • Petri dishes (or other recipient)

How to prepare?

  1. We prepared a solution of calcium chloride. For this, we dissolved Calcium Chloride in water (1g per 100ml).

  2.  Then, we dissolved Sodium Alginate in water, which will be the material for your slimy worms. You’ll probably need to use the warm water here and stir quite a lot!

  3. Finally, we added food colouring to make everything easier to see, fancier and more beautiful

  4. Use a syringe to take some coloured alginate from our bottles.

  5.   Go to one of our Petri dishes (scientific name for the small and round plastic trays placed on the table) which contain some solution of calcium chloride and press your syring to create the worms.

  6. Use your hands and squish the worms!!

Some science behind it

§  The worms you have made are made of calcium alginate. Alginate is a polymere, that is, a chain of many, many, many identical molecules. Polymeres can be either natural (like alginates) or human-made (like plastics).

§  Some brown species of seaweed such as kelp (Laminaria sp.) naturally produce alginates. These algae are very common in Scottish waters and play an important role in our marine ecosystems.

§  You also produce polymers! Glycogen is a polymere made up of long chains of sugar that our muscles produce to store energy.

§  Some medicines, like Gaviscon®, use alginates to protect the drug from the acids in your tummy,

Risks & Important Stuff

There are no many risks associated to this activity, more than the use of warm water. The worms are actually edible, but we do not recommend to eat them under any circumpstance.