(369e) Sensor Integrated Continuous Microfluidic Mixer for Protein Screening at Constant Supersaturation

Sensors are great assets to quick and sensitive detection inside miniaturized devices were the amount of sample is small. Connecting an integrated microfluidic system to a control unit increases the accuracy of the experiments due to the automated adjustments of parameters. One of the examples for the potential application of a sensor integrated microfluidic system is screening crystalline materials where there is a high demand for accurate measurement of the concentration within the crystallization zone. In our previous studies, we developed a continuous microfluidic mixer for screening crystalline materials at the constant supersaturation, where the homogeneous concentration was calculated using COMSOL Multiphysics. However, it was not possible to perform an in-situ measurement for the actual concentration to experimentally verify that. Here we have coupled the microfluidic mixer design with an electrochemical sensor to enable in-situ measurement of the actual concentration inside the mixing zone. Moreover, integration of a sensor within the continuous microfluidic platform we can control the imposed supersaturation by manipulation of the flowrates. To validate the sensor integrated platform experimentally, we have done the protein crystallization of lysozyme and NaCl. Products of this crystallization process can exhibit different morphologies according to the ratio of the starting solutions. Several different experimental conditions are explored to study the morphologies obtained at assigned initial concentration as well as the growth kinetics.