The advantages of immobilized over soluble enzymes arise from their enhance
d stability and ease of separation from the reaction media, leading:to sign
ificant savings in enzyme consumption. Immobilization methods range from bi
nding to prefabricated carrier materials to packaging in enzyme crystals or
powders. During their use, mass-transfer effects can produce substrate or
pH gradients, which reduce the reaction rates and product yields. The costs
of immobilized enzymes must be minimized in order to increase their compet
itiveness for technical applications.