Engineering aspects of FlowNMR spectroscopy setups for online analysis of solution-phase processes

Abstract

Online analysis and monitoring of solution phase chemistry by way of nuclear magnetic resonance spectroscopy on a recirculating sample from an external reaction vessel (FlowNMR) has proven to be a valuable tool for understanding the dynamic behaviour of complex solution-phase systems in real time. A variety of flow cells and setups have been used at both low and high magnetic field strengths for various applications, and the choice of materials, dimensions and components can have a profound impact on the quality and relevance of the data obtained. Here we review some fundamental engineering aspects of FlowNMR setups to help avoid common pitfalls and work towards establishing good practice quality guidelines (GxP) for FlowNMR investigations in academia and industry.