Undergraduate Research Center

Posters at the Capitol 2010

Keaten Holley (left) pictured with Dr. Andrienne Friedli

Department of Physics
Middle Tennessee State University
Mentor: Dr. Daniel Erenso Link to: POSTER

Elasticity of human red blood cells (RBCs) is studied by means of laser tweezers exerting forces to cause mechanical deformations to the cells in a particular environment. In this case we have studied elasticity of fresh RBCs as compared to refrigerated RBCs in their own human blood serum. The deformations we have observed have been the result of dragging an RBC through a viscous fluid. A more typical method of directly deforming human RBCs with laser tweezers requires exposure of a cell to two laser traps at once. This exposure to high energy photons brings the cell membrane's structural integrity into question. We thus opted to use this unique method of having a viscous drag force oppose the force of a single laser trap as means of deformation. The validity of our measurements is hoped to be assessed using the dual laser trap method measurements taken in human blood serum using the same laser tweezers setup. We found some interesting, non-linear behavior between the net force on the red blood cell and its longitudinal displacement, contrasting that of typical stretching measurements with force probes. Our current focus is to investigate the elasticity of blood cells infected with sickle cell anemia. As only refrigerated blood is available for these types of measurements, refrigeration effects have become pertinent as to validate our current measurements observing deformation of sickle RBCs as we continue to research this area of study.