Figure 5.

(A) Schematic diagram for measuring blood viscosity under an unknown flow rate supplied by a peristaltic pump. Most of the blood samples were circulated in the closed fluidic network, which includes a reservoir, a peristaltic pump, and the left side channel of the microfluidic device. (B) Temporal variations of blood flow rate with a periodic (T = 2.92 ± 0.12 s), supplied by the peristaltic pump which operated at a pumping speed of ω = 2. After passing through the half-circular chamber of the microfluidic device, the fluctuations in blood flow rate was completely removed owing to the compliance effect of the chamber. The number of indicating channels filled with blood in the right side channel (N_Blood) was kept consistent at 15 (N_Blood = 15), which is equivalent to the blood flow rate of Q_Blood = 5 mL/h, as identified by the experimental procedure using the blood samples collected from the outlet (A). (C) Variations of viscosity (μ_Blood) and flow rate (Q_Blood) of blood sample with respect to hematocrits ranging from 20% to 50%. (D) Variations in N_Blood and Q_Blood with respect to the pumping speeds from ω = 2 to ω = 3. The inset represents the relationship between Q_Blood and N_Blood.