Reported herein is an entrapment method for enzyme immobilization
that does not require the formation of new covalent bonds. Ionic liquid
supramolecular gels are formed containing enzymes that can be shaped
into gel beads and act as recyclable immobilized biocatalysts. The
gel was formed from two components, a hydrophobic phosphonium ionic
liquid and a low molecular weight gelator derived from the amino acid
phenylalanine. Gel-entrapped lipase fromAneurinibacillus
thermoaerophiluswas recycled for 10 runs over 3 days without
loss of activity and retained activity for at least 150 days. The
procedure does not form covalent bonds upon gel formation, which is
supramolecular, and no bonds are formed between the enzyme and the
solid support.