No abstract

Data processing of force-displacement curves generated by atomic force microscopes (AFMs) for elastic moduli and unbinding event measurements is very time consuming and susceptible to user error or bias. There is an evident need for consistent, dependable, and easy-to-use AFM data processing software. We have developed an open-source software application, the force review automation environment (or FRAME), that provides users with an intuitive graphical user interface, automating data processing, and tools for expediting manual processing. We did not observe a significant difference between manually processed and automatically processed results from the same data sets.

Current microfluidic assays, which aim at quantifying mechanical properties of sickle cell red blood cells (SS-RBCs), suffer from a number of drawbacks in functionalization and flow control. Specifically, physical adsorption functionalization techniques produce inconsistent functional surfaces, and common volumetric flow pumps cannot be used to adjust the flow inside microchannels with minimal delay. We have designed an experimental setup that alleviates these complications by implementing aspiration for microchannel assembly that enables the use of most functionalization techniques and a pressure controller that allows instant and precise changes in the microchannel flow. Utilizing this setup, we have quantified SS-RBC adhesion to the integrin αvβ3, a specific adhesion protein expressed on the endothelium, as well as measured the shear modulus and viscosity of the SS-RBC plasma membrane.