IGEM:IMPERIAL/2009/cell encapsulation methods

Alginate encapsulation
Sodium alginate forms solid gel upon complexation with Ca2+.

Advantages

 * mild
 * non-toxic
 * low cost
 * ease of handling

Disadvantages

 * leaking (for pure alginate)

Spray coating of fats
Active material dissolved in polymer and trapped in dried particle.

Advantages

 * Can handle labile particles due to short contact time

Disadvantages

 * Must be heat resistant for spray-dry encapsulation

Rennet- Gelling
Milk proteins form gels upon Rennet action

Advantages

 * milk is common food item

Disadvantages

 * storage problem

Crystal Layer
Cell is encapsulated in a salt crystal

Advantages

 * Outer layer coating controlled by cell
 * can be visually seen

Disadvantages

 * Unable to secrete
 * Broken down easily in stomach acid

| Crystal Encapsulation Tutorial