IGEM:IMPERIAL/2009/alginate encapsulation
Pure alginate encapsulation
resistance to acidity
entrapment of bifidobacteria in alginate microspheres
diameters of 40–80 μm
- insignificant protection
larger alginate (1–3 mm) microspheres
- protected entrapped cells
methodology
1) cell in gelatin microsphere
2) Alginate solution was added. Kept for 20 min
3) CaCl2 added for 20 min to initiate the external Ca2+ cross-linking of the peripheral alginate layer
Paper for encapsulation in alginate and acidity tests
alginate–chitosan–alginate (ACA)
one of the most widely studied microcapsules for its good biocompatibility and the low cost of chitosan
By having alginate crosslinked with other molecules, this reduces the leakage of drugs from the microcapsule
methodology
1) microbial cells obtained by high speed centrifugation were suspended in 1.5% alginate solution 2) The cell-alginate suspension was extruded into 100 mM CaCl2 solution 3) The microbeads were hardened for 30 min. Chitosan solution was added. 4) alginate solution was added to counteract excess charges on the membranes
Metabolic activity of E.coli in ACA
an innovative method for cultivating microorganisms by encapsulating them within agar spheres
Alginate and chitosan review