Point of care diagnostic of the non-linear rheology of biofluids

Treballs Finals de Grau de Física, Facultat de Física, Universitat de Barcelona, Curs: 2020, Tutor: Aurora Hernández-MachadoWe determine the theoretical model for the characterization of the behaviour of Newtonian and non-Newtonian fluids inside a microchannel with segments of different widths. This is done in order to examine the accuracy of a prototype which consists in microscale electronic detection of a fluid/air front advance in order to disclosure different diseases that can be distinguished by the change in the normal rheological characteristics of blood or plasma. We will also test the accuracy of the device when examining Newtonian fluids

Blood Rheological Characterization of β-Thalassemia Trait and Iron Deficiency Anemia Using Front Microrheometry

The purpose of this work is to develop a hematocrit-independent method for the detection of beta-thalassemia trait (β-TT) and iron deficiency anemia (IDA), through the rheological characterization of whole blood samples from different donors. The results obtained herein are the basis for the development of a front microrheometry point-of-care device for the diagnosis and clinical follow-up of β-TT patients suffering hematological diseases and alterations in the morphology of the red blood cell (RBC). The viscosity is calculated as a function of the mean front velocity by detecting the sample fluid-air interface advancing through a microfluidic channel. Different viscosity curves are obtained for healthy donors, β-TT and IDA samples. A mathematical model is introduced to compare samples of distinct hematocrit, classifying the viscosity curve patterns with respect to the health condition of blood. The viscosity of the fluid at certain shear rate values varies depending on several RBC factors such as shape and size, hemoglobin (Hb) content, membrane rigidity and hematocrit concentration. Blood and plasma from healthy donors are used as reference. To validate their potential clinical value as a diagnostic tool, the viscosity results are compared to those obtained by the gold-standard method for RBC deformability evaluation, the Laser-Optical Rotational Red Cell Analyzer (LoRRCA).LM-M and JF-T received funding from programs Doctorat Industrial (2018 DI 068) and (2018 DI 064) from AGAUR (Generalitat de Catalunya). EK receives funding from Institut Josep Carreras (IJC) under program Equality Plus, project number 2019-1-TR01-KA202-076789. TA acknowledges funding under grant numbers MTM2015-71509-C2-1-R and MDM-2014-0445. TA has been partially funded by the CERCA Program of the Generalitat de Catalunya. AH-M acknowledges funding under project FIS2016-78883-C2-1P, Ministerio de Ciencia e Innovacion (Spain) under project PID2019-106063GB-100 and AGAUR (Generalitat de Catalunya) under project 2017 SGR-1061. CT-S and AH-M acknowledge partial support from ANID/PCI (Chile) under project MEC80180021

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

Altres ajuts: Generalitat de Catalunya: 2018/DI-068, 2018/DI-064The 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