High throughput urease immobilization onto a new metal-organic framework called nanosized electroactive quasi-coral-340 (NEQC-340) for water treatment and safe blood cleaning

Abstract

In this contribution, urease was efficiently immobilized onto the new MOF called NEQC-340 for utilizing toward safe blood cleaning and water treatment. Upon this immobilization, the biochemical properties, shelf-life, and reusability of the enzyme were enhanced. The NEQC-340 was synthesized using tris(p-aminophenyl)amine as the amino-linker. The NEQC-340 was characterized by FT-IR, EDX, XRD, SEM, and DLS analysis and then used for urease immobilization (NEQC-340@Urease). The immobilization efficiency was calculated as 90.0 % along with retaining about 87.7 % of enzyme initial activity at optimal conditions. The best pH for both urease and NEQC-340@Urease was found to be 7.0 while the optimum temperature was estimated at about 37.0 °C and 45.0 °C for the free urease and NEQC-340@Urease, respectively. The value of Km was calculated as 22.65 mM and 33.28 mM and the Vmax was found to be 5.26 μmol mg−1 min−1 and 4.41 μmol mg−1 min−1 for the free urease and NEQC-340@Urease, respectively. Moreover, 81.0 % of NEQC-340@Urease initial activity was saved after 15 days of storage, also, it was retained 55.0 % of its activity after 10 reuse. Since NEQC-340@Urease derivatives showed high blood compatibility, they were utilized for both safe blood cleaning (efficiency, 87.0 %) and water bio-treatment (efficiency, 91.0 %) via urea biodegradation.