Versatile automated continuous flow system (VersAFlo) for bioanalysis and bioprocess control

Abstract

Flow injection analysis provides a convenient platform for the use of biosensors in the monitoring of bioprocesses. A major requirement in bioprocess monitoring is real time information about various process parameters like concentration of products and substrates, flow rates, and injection volumes. Depending on the application, the monitoring requirements vary and this results in a need for different measurement flow schemes. Common flow schemes employed with biosensing are FIA, SIA, BIA and multi-commuted flow. In this work, a versatile platform to employ biosensors for continuous analysis of bioprocesses with precise control of flow, volume and defined events has been developed. The system is based on National Instruments LabVIEW and employs piston-, peristaltic pumps, motorized injection valves and 2-way and 3-way solenoid valves. The system supports data acquisition, controls interface with devices and visualization of data from multiple detectors used in biosensing. The system was successfully evaluated for the analysis of a model analyte, human immunoglobulin G (IgG), employing continuous flow-ELISA in competitive mode with optical detection. The flow-immunosensor showed very good linearity; from 5 to 400 μg/ml. The system had excellent reproducibility and stability with a relative standard deviation of 4.75%. The immunosensor was also subjected to a model first order kinetics of target analyte concentration and the results from the sensor agreed well with the estimated concentration. The flexibility of the system gives that different flow configurations easily can be set up and the dynamic range of analysis can be adapted by varying different flow conditions for measurement, thereby controlling different reaction times in the biosensor system. The system could be useful for online analysis and control of bioprocesses employing biosensors. Further, with automated data collection and analysis, the system provides excellent basis for cross platform data communication for integrated control.