The visible light transmittance of the membrane was measured with a UV-vis spectrometer (GENESYS 15, Thermo Scientific). The morphology and microstructure of these To effectively replicate the unhealthy blood of CKD patients, 25 distinct uremic toxins (Table ) were added to plasma prior to incubation with PCL sheets. A complex solution containing these UTXs was precisely prepared, divided into aliquots, frozen(-80 o C), freezedried, added to 1 mL of plasma as a powder, mixed thoroughly, and allowed to dissolve completely over a 30 min period at room temperature.