Jun 05, 2025
Sodium Alginate Hydrogel with Crosslinking
- Miranda Shou1
- 1University College London (UCL)
Protocol Citation: Miranda Shou 2025. Sodium Alginate Hydrogel with Crosslinking. protocols.io https://dx.doi.org/10.17504/protocols.io.4r3l2pw6jg1y/v1
License: This is an open access protocol distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited
Protocol status: Working
We use this protocol and it's working
Created: June 05, 2025
Last Modified: June 05, 2025
Protocol Integer ID: 219691
Keywords: sodium alginate hydrogel with crosslinking instruction, sodium alginate hydrogel, based sodium alginate, sodium alginate, cyanobacteria, algae, crosslinking instruction, alginate hydrogel, sodium
Abstract
Instructions for how to make cyanobacteria/algae based sodium alginate based hydrogel
Guidelines
Be careful when pouring boiling hot water, carrying your mug of tea, and ensure it has cooled a bit before you drink it.
Materials
Water, Water kettle, Your favourite mug, PG Tips English teabags, Skimmed (0%) milk, Spoon, McVities Digestive biscuit.
Troubleshooting
Prepare and Weigh the Raw Materials
Weigh 2.4g sodium alginate, 2.6g methylcellulose, 45 ml of DI water, 0.1M calcium chloride spray (1.1g CaCl2 powder dissolved in 100ml DI water).
Mixing Materials
Mix sodium alginate, methylcellulose, and DI water in a beaker until most of the large particles are dissolved.
It is a bit tricky to mix all of the material at once. It could be easier to add the dry powders first and DI water portion by portion to mix all material in a gelatinous consistency. Use an overhead mixer if making a large portion of the gel.
Wait for Material Gelling
Seal the material mix on the side for 30 minutes.
Add Algae/Cyanobacteria in the Hydrogel
Add 1% of microbial culture in the hydrogel with a spatula. Mix the culture and hydrogel well into a homogeneous culture.
Use the microbial hydrogel in applications like biophotovoltaics or engineered living materials.
Ready to Use
Depends on uses, crosslink the alginate material by spraying with a 0.1M CaCl2 mist on the top surface or soaking it in a 0.1M CaCl2 bath for cross surface crosslinking effect.