Multicommutation in Flow Systems: A Useful Tool for Pharmaceutical and Clinical Analysis

Multicommutation is a methodology of increasing use for the development of chemical analysis systems. Specifically, it refers to continuous-flow configurations designed with computer-controlled commutators. The flow system, based on the implementation of solenoid valves in Flow Injection Analysis (FIA), is called Multicommutated Flow System (MCFIA). These flow systems can be easily re-configured by just changing the procedure with the software, resulting in increased versatility, potential for automation and minimization of both reagent consumption and waste generation. The use of solenoid pumps for propelling the solutions has been recently introduced and is known as Multipumping Flow Systems (MPFS). Finally, Multisyringe Flow Injection Analysis (MSFIA) has been developed implementing multicommutation principles in a modified Sequential Injection Analysis (SIA) system. This review covers a brief description about the fundamentals of the above mentioned methodologies as well as their application to pharmaceutical and clinical analysis. Several examples are given and some particular aspects are highlighted, such as the differences between measuring the analytical signal in solution or on a solid support (flow-through optosensor), a detailed classification of the reported methods in terms of the flow technique employed, or the novelty of each published method.