Dissertation
The flow of sickle blood through glass capillaries and its diagnostic implications
Doctor of Philosophy (Ph.D.), Drexel University
Jul 2018
DOI:
https://doi.org/10.17918/D8SQ2J
Abstract
Sickle Cell Anemia is a genetic disease arising from a point mutation on the [beta]-subunit of hemoglobin, the oxygen-carrying protein found in red blood cells. This change in a single amino acid ([beta]6: Glu to Val) leads to polymerization of sickle hemoglobin into stiff fibers that cause the cell to become rigid upon deoxygenation. Sickle cell disease affects approximately 80,000 Americans, and it is estimated that 300,000 children are born each year with sickle cell disease. In this work we investigate whether there is sufficient information contained within the flow of blood through narrow glass capillaries to detect the presence of sickle hemoglobin. Blood samples are observed to flow through these capillaries via capillary action, and a relative viscosity is deduced. We observe the flow of blood in both oxygenated and deoxygenated states. We observe the deoxygenated flow of blood is considerably slower than the flow of oxygenated blood for sickle blood, while there is no change in AA blood. We find that the relative viscosities for oxygenated and deoxygenated blood vary by genotype. Sickle disease detection is most reliably achieved by observing the ratio of deoxygenated to oxygenated relative viscosity. We find an average ratio value of 2.8 for sickle genotypes, while the ratio for AA was measured as 1.1. We find that the sickle genotypes are distinguishable as well, though with less resolution. The method is expected to be resistant to confounding effects such as temperature differences and viscosity increasing conditions, such as malarial infections. We find that this method is able to indicate the presence of anemia as well as sickle cell therapy efficacy. We also report on the formation of a dense phase behind the advancing meniscus in deoxygenated sickle blood flow experiments. This cap grows linearly with displacement. We find the cap to be the probable source of the deviation from Lucas-Washburn behavior. An analysis of all deoxygenated flow measurements showed that these characteristic deviations can be described by an added back-pressure in the Lucas-Washburn equation. This back-pressure term was found to be of the same functional form as the hydrostatic back-pressure due to gravity in the vertical rise through capillaries.
Metrics
23 File views/ downloads
30 Record Views
Details
- Title
- The flow of sickle blood through glass capillaries and its diagnostic implications
- Creators
- Christopher D. Brown - DU
- Contributors
- Frank Ferrone (Advisor) - Drexel University (1970-)
- Awarding Institution
- Drexel University
- Degree Awarded
- Doctor of Philosophy (Ph.D.)
- Publisher
- Drexel University; Philadelphia, Pennsylvania
- Number of pages
- xiii, 148 pages
- Resource Type
- Dissertation
- Language
- English
- Academic Unit
- College of Arts and Sciences; Physics; Drexel University
- Other Identifier
- 8121; 991014632233304721