Investigation of enhancement in thermal stability of trypsin in modified Mg/Al layered double hydroxides

Abstract

Mg/Al Layered Double Hydroxides (LDHs) were functionalized to immobilize the serine protease, trypsin. Three methods were implemented for immobilization: physical adsorption, entrapment and covalent cross-linking. Trypsin was immobilized in Mg/Al-NO 3-LDH via simple adsorption. The same LDH host was modified with Sodium Dodecyl Sulphate (SDS) which assembles inside the double layer, for the enzyme to be entrapped. For covalent cross linking, LDH host was modified with vertical pillars of glutamate ions which were cross-linked to horizontally aligned dicarbonyl linkers. This cross linkage firmly holds the enzyme via Schiff's base linkages using the free amino groups of the enzyme. Thermal stability and storage stability of the immobilized enzyme was studied in comparison with the free enzyme using trypsin activity assay experiments. The enzyme showed remarkable stability against autolysis even at higher temperatures showing the potential of modified LDHs to store trypsin at room temperature.

Review on sterilization techniques, and the application potential of phage lyase and lyase immobilization in fighting drug-resistant bacteria

“…Different proteins, such as trypsin, glucose oxidase, and laccase, were immobilized by the embedding method. [110][111][112]…”

“…Different proteins, such as trypsin, glucose oxidase, and laccase, were immobilized by the embedding method. 110–112 The embedding process is similar to adsorption in that it does not modify the enzyme, preserving its original structure and reducing enzyme activity loss. The embedding of laccase was successfully prepared on a polyn-isopropyl acryphthalide microgel by polymerization.…”