Abstract: Device for removing substances from blood and other fluids such as water, wastewater, chemicals and other biofluids, includes i) an electrocatalytic decomposition filter including a DC power source, a set of electrodes with a catalytic surface or in direct contact with sorbents offering catalytic activity, ii) an electrosorption filter including a DC power source, a set of electrodes, nanostructured sorption material and/or a porous polymer matrix, iii) an inlet for entry of blood or blood plasma or dialysate fluid into the device, iv) an outlet for the removal of purified blood, blood plasma, ultrafiltrate or dialysate fluid from the device, and v) a conduit connecting the inlet with the outlet and holding the electrosorption filter such that the blood, blood plasma, ultrafiltrate or dialysate fluid is forced through the electrosorption and electrocatalytic decomposition filter, and vi) a sensor and control system to safeguard the device from producing oxidative stress.