Abstract
Erythrocytes can be used to entrap drugs, enzymes or other molecules with active properties, with various encapsulation procedures. The carrier is nonimmunogenic, biodegradable, and circulates freely throughout the body. Urease was covalently immobilized on activated methoxypolyethyleneglycol-5000 (PEG-5000) (1:3 molar ratio). Urease and PEG-Urease were encapsulated in erythrocyte (1/1) (v/v) by using slow dialysis methods. To optimize the loading of erythrocyte, the above base procedure was varied to test the effect of some parameters. Dialysis time, dialysis temperature, storage condition for erythrocyte conjugate, Urease and PEG-Urease concentration were investigated.