*2.1. Blood Collection*

Fresh total blood was collected from the jugular veins of 3 healthy adult male sheep (aged about 4 years old, with a body weight of around 80 kg) for fixed shear stress and microfluidic channel tests. A large bore needle (16G) was applied to collect 400 mL blood into a 500 mL sterile PVC bag prefilled with 56 mL of citrate phosphate dextrose adenine (CPDA-1) anticoagulant; the procedure was performed according to American Society for Testing Materials (ASTM) Standard Practices F1830, and the aseptic technique was followed strictly. The fresh sheep blood was stored and transported with the temperature between 2 and 8 ◦C, and the time interval from collection to experiment was within 8 h. Before the experiment started, the collected sheep blood was kept quiescent in room temperature and rewarmed slowly to 24 ◦C while maintaining the temperature of 37 ◦C with a water bath during

the experiment process. According to ASTM Standard Practices F1841, the hematocrit of blood applied in the tests was adjusted to 30% by a phosphate-buffered saline.
