Microrheometer for Biofluidic Analysis: Electronic Detection of the Fluid-Front Advancement

• Main Authors: Lourdes Méndez-Mora, Maria Cabello-Fusarés, Josep Ferré-Torres, Carla Riera-Llobet, Samantha Lopez, Claudia Trejo-Soto, Tomas Alarcón, Aurora Hernandez-Machado
• Format: Article
• Language: English
• Published: MDPI AG 2021-06-01
• Series: Micromachines
• Subjects: rheometer; microrheometer; rheology; hemorheology; viscosity; blood
• Online Access: https://www.mdpi.com/2072-666X/12/6/726

The motivation for this study was to develop a microdevice for the precise rheological characterization of biofluids, especially blood. The method presented was based on the principles of rheometry and fluid mechanics at the microscale. Traditional rheometers require a considerable amount of space, are expensive, and require a large volume of sample. A mathematical model was developed that, combined with a proper experimental model, allowed us to characterize the viscosity of Newtonian and non-Newtonian fluids at different shear rates. The technology presented here is the basis of a point-of-care device capable of describing the nonlinear rheology of biofluids by the fluid/air interface front velocity characterization through a microchannel. The proposed microrheometer uses a small amount of sample to deliver fast and accurate results, without needing a large laboratory space. Blood samples from healthy donors at distinct hematocrit percentages were the non-Newtonian fluid selected for the study. Water and plasma were employed as testing Newtonian fluids for validation of the system. The viscosity results obtained for the Newtonian and non-Newtonian fluids were consistent with pertinent studies cited in this paper. In addition, the results achieved using the proposed method allowed distinguishing between blood samples with different characteristics.