Method

List of Reagents and Instruments

A. Equipment

• Beakers
• Graduated cylinder
• Pipets
• Constant temperature bath
• Freezer

B. Reagents

• Gelatin Solution, 10 wt%
• Hardening Solution
  • 20 vol% Formaldehyde
  • 50 vol% Ethanol
  • 30 vol% Water
• Enzyme

Procedures

1. Dissolve 10 g gelatin in 100 ml of water to prepare a 10% (wt.) aqueous solution. Heating the solution gently to facilitate the dissolution process.
2. Adjust the temperature of the gelatin solution to 35-40ºC. The temperature is kept relatively high so that the gelatin solution is not too viscous, but not so high as to cause enzyme denaturation.
3. Add approximately 0.015 g of the enzyme powder (or an equivalent of concentrated enzyme solution) to 10 ml of the gelatin solution.
4. Add 2 ml of the Hardening Solution to the above enzyme solution.
5. Pour the solution into a mold or a small beaker. Freeze at -28ºC for 4 hours to facilitate the gel formation. If this temperature is not readily available, a regular freezer will also suffice for the purpose of demonstrating the technique.
6. When the gel is set, warm the gel to room temperature simply by leaving it on a lab bench.
7. Cut the gel into small cubes of approximately 3mm per side.
8. Gently wash the gel liberally with deionized water.

Discussions

References

1. E. de Alteriis, P. Parascandola, S. Salvadore, and V. Sardi, Enzyme immobilization within insolubilized gelatin, J. Chem. Tech. Biotechnol., 35B, 60, 1985.