by Keyword: Enzyme immobilization
Witzdam, L, Vosberg, B, Grosse-Berkenbusch, K, Stoppelkamp, S, Wendel, HP, Rodriguez-Emmenegger, C, (2024). Tackling the Root Cause of Surface-Induced Coagulation: Inhibition of FXII Activation to Mitigate Coagulation Propagation and Prevent Clotting Macromolecular Bioscience 24, e2300321 
Factor XII (FXII) is a zymogen present in blood that tends to adsorb onto the surfaces of blood-contacting medical devices. Once adsorbed, it becomes activated, initiating a cascade of enzymatic reactions that lead to surface-induced coagulation. This process is characterized by multiple redundancies, making it extremely challenging to prevent clot formation and preserve the properties of the surface. In this study, a novel modulatory coating system based on C1-esterase inhibitor (C1INH) functionalized polymer brushes, which effectively regulates the activation of FXII is proposed. Using surface plasmon resonance it is demonstrated that this coating system effectively repels blood plasma proteins, including FXII, while exhibiting high activity against activated FXII and plasma kallikrein under physiological conditions. This unique property enables the modulation of FXII activation without interfering with the overall hemostasis process. Furthermore, through dynamic Chandler loop studies, it is shown that this coating significantly improves the hemocompatibility of polymeric surfaces commonly used in medical devices. By addressing the root cause of contact activation, the synergistic interplay between the antifouling polymer brushes and the modulatory C1INH is expected to lay the foundation to enhance the hemocompatibility of medical device surfaces.© 2023 The Authors. Macromolecular Bioscience published by Wiley-VCH GmbH.
JTD Keywords: adsorption, binding, c1-esterase-inhibitor, coatings, contact activation, factor-xii, fxii activation, hemocompatibility, hemocompatible surface modification, heparin, polymer brushes, system, thrombosis, Adsorption, Anticoagulation, Antifouling agent, Article, Beta-fxiia, Biocompatibility, Blood, Blood clotting, Blood clotting factor 12, Blood clotting factor 12a, Blood clotting factor 12a inhibitor, Blood coagulation, C1-esterase-inhibitor, Cell activation, Chemical activation, Coagulation, Coating (procedure), Complement component c1s inhibitor, Complement system, Controlled study, Dendrimers, Enzyme immobilization, Enzymes, Erythrocyte, Esters, Factor xii, Factor xii activation, Factor xiia, Fibrin deposition, Functional polymers, Fxii activation, Haemocompatibility, Hemocompatibility, Hemocompatible surface modification, Hemostasis, Heparin, Human, Hydrogel, Medical devices, Metabolism, Plasma kallikrein, Plasma protein, Plastic coatings, Platelet count, Polymer, Polymer brushes, Polymerization, Polymers, Property, Root cause, Surface plasmon resonance, Surface property, Surface reactions, Surface-modification, Thrombocyte adhesion, Β-fxiia
Apriceno, A, Silvestro, I, Girelli, A, Francolini, I, Pietrelli, L, Piozzi, A, (2021). Preparation and characterization of chitosan-coated manganese-ferrite nanoparticles conjugated with laccase for environmental bioremediation Polymers 13, 1453
Bioremediation with immobilized enzymes has several advantages, such as the enhancement of selectivity, activity, and stability of biocatalysts, as well as enzyme reusability. Laccase has proven to be a good candidate for the removal of a wide range of contaminants. In this study, naked or modified MnFe O magnetic nanoparticles (MNPs) were used as supports for the immobilization of laccase from Trametes versicolor. To increase enzyme loading and stability, MNPs were coated with chitosan both after the MNP synthesis (MNPs-CS) and during their formation (MNPs-CS ). SEM analysis showed different sizes for the two coated systems, 20 nm and 10 nm for MNPs-CS and MNPs-CS , respectively. After covalent immobilization of laccase by glutaraldehyde, the MNPs-CS -lac and MNPs-CS-lac systems showed a good resistance to temperature denaturation and storage stability. The most promising system for use in repeated batches was MNPs-CS -lac, which degraded about 80% of diclofenac compared to 70% of the free enzyme. The obtained results demonstrated that the MnFe O -CS system could be an excellent candidate for the removal of contaminants. 2 4 in situ in situ in situ in situ 2 4 in situ
JTD Keywords: bioremediation, chitosan, diclofenac, diclofenac removal, immobilized enzyme, laccase, magnetic nanoparticles, phase, removal, supports, Bioremediation, Chitosan, Diclofenac removal, Enzyme immobilization, Immobilized enzyme, Laccase, Magnetic nanoparticles