Hemocompatible surfaces

The interaction of blood and material is crucial to the success of blood-contacting medical devices. The morbidity arising from the material-induced thrombosis along with the risk of infections are the major limiting factors of a wide range of implantable biomedical devices including complex extracorporeal membrane oxygenators (ECMOs) used in artificial lungs-supporting systems. In contrast to the healthy endothelium, which actively resists thrombosis, artificial surfaces promote adverse interactions with blood components including protein adsorption, platelet activation-aggregation, and activation of complement and inflammation. Long-term use of anticoagulants to counteract this often exposes patients to hemostasis disorders and at the risk of hemorrhage. We aim to develop active biocompatible surface coatings for medical devices, particularly ECMO surfaces to reduce protein fouling, thrombosis, and infection. This, in turn, will prolong the lifetime of ECMO, assist in miniaturizing the complex artificial lungs assisting system and potentially reduce the amount of anticoagulants used.

(A) Schematic illustration of the semi-static blood experiment evaluating the antiplatelet effect of the microgel coating. The washed coated TPX membranes after incubation with human whole blood for 90 min visually indicate the effect of microgel coating towards clot formation (B) The visual inspection of the ECMO fibers right after the blood flow experiment. SEM micrographs revealing the status of clot formation on membrane surfaces after exposing to blood: (C) bare membrane showing the red blood cells embedded in the tangled fibrin network (D) The washed surface of the coated membrane (E) periphery of the coated membrane (F) the absence of any fibrin network on the surface of the coated fiber (G) bare fiber with a dense layer of clot formed after contacting the blood inflow.

Smriti Singh

(A) Schematic illustration of the semi-static blood experiment evaluating the antiplatelet effect of the microgel coating. The washed coated TPX membranes after incubation with human whole blood for 90 min visually indicate the effect of microgel coating towards clot formation (B) The visual inspection of the ECMO fibers right after the blood flow experiment. SEM micrographs revealing the status of clot formation on membrane surfaces after exposing to blood: (C) bare membrane showing the red blood cells embedded in the tangled fibrin network (D) The washed surface of the coated membrane (E) periphery of the coated membrane (F) the absence of any fibrin network on the surface of the coated fiber (G) bare fiber with a dense layer of clot formed after contacting the blood inflow.

Smriti Singh

1. Hosseinnejad, A.; Fischer, T.; Jain, P.; Bleilevens, C.; Jakob, F.; Schwaneberg, U.; Rossaint, R.; Singh, S.*, Enzyme mimetic microgel coating for endogenous nitric oxide mediated inhibition of platelet activation. Journal of colloid and interface science 2021, 601, 604-616.

2. Hosseinnejad, A.; Ludwig, N.; Wienkamp, A. K.; Rimal, R.; Bleilevens, C.; Rossaint, R.; Rossaint, J.; Singh, S.*, DNase I functional microgels for neutrophil extracellular trap disruption. Biomaterials science 2021, 10 (1), 85-99.