Antibody Purification through the use of Protein Hydrogels
Mentor 1
Ionel Popa
Location
Union Wisconsin Room
Start Date
27-4-2018 1:00 PM
Description
Here we describe a force-clamp rheometry method to characterize biomechanical properties of protein-based hydrogels. Our method uses an analog proportional-integral-derivative (PID) system to apply controlled-force protocols on cylindrical protein-based hydrogel samples, which are tethered between a linear voice-coil motor and a force transducer. During operation, the PID system adjusts the extension of the hydrogel sample to follow a predefined force protocol by minimizing the difference between the measured and setpoint forces. This unique approach of protein-based hydrogel attachment enables tethering extremely low-volume hydrogel samples (< 5 µL) with different protein concentrations. Under force ramp protocols, where the applied stress increases and decreases linearly in time, the system enables the study of the elasticity and hysteresis behavior associated with the (un)folding mechanics of protein-based hydrogel samples and to measure the standard elastic and visco-elastic parameters. Under constant-force, where the force pulse has a square-like shape, the elastic response due to the change in force is decoupled from the visco-elastic response, which comes from protein domain unfolding and refolding. Due to its low-volume sample and versatility in applying various mechanical perturbations, force-clamp rheometry is optimized to investigate the mechanical response of proteins under force using a bulk approach.
Antibody Purification through the use of Protein Hydrogels
Union Wisconsin Room
Here we describe a force-clamp rheometry method to characterize biomechanical properties of protein-based hydrogels. Our method uses an analog proportional-integral-derivative (PID) system to apply controlled-force protocols on cylindrical protein-based hydrogel samples, which are tethered between a linear voice-coil motor and a force transducer. During operation, the PID system adjusts the extension of the hydrogel sample to follow a predefined force protocol by minimizing the difference between the measured and setpoint forces. This unique approach of protein-based hydrogel attachment enables tethering extremely low-volume hydrogel samples (< 5 µL) with different protein concentrations. Under force ramp protocols, where the applied stress increases and decreases linearly in time, the system enables the study of the elasticity and hysteresis behavior associated with the (un)folding mechanics of protein-based hydrogel samples and to measure the standard elastic and visco-elastic parameters. Under constant-force, where the force pulse has a square-like shape, the elastic response due to the change in force is decoupled from the visco-elastic response, which comes from protein domain unfolding and refolding. Due to its low-volume sample and versatility in applying various mechanical perturbations, force-clamp rheometry is optimized to investigate the mechanical response of proteins under force using a bulk approach.
