A monosegmented flow-batch system for slow reaction kinetics: Spectrophotometric determination of boron in plants

► This study introduces the first monosegmented flow-batch (MSFB) system. ► The MSFB combines favourable characteristics of both FBA and MSFA. ► Slow kinetics applied without impairing the sensitivity or sampling throughput. ► The MSFB displays high frequency (and discrete) sampling throughput. ► Calibration solutions prepared in-line. This work introduces the monosegmented flow-batch (MSFB) analysis concept. This system combines favourable characteristics of both flow-batch and the monosegmented analysers, allowing use of the flow-batch system for slow reaction kinetics without impairing sensitivity or sampling throughput. The MSFB was evaluated during spectrophotometric determination of boron in plant extracts, which is a method that involves a slow reaction between boron and azomethine-H. All calibration solutions were prepared in-line, and all analytical processes completed by simply changing the operational parameters in the MSFB control software. The limit of detection was estimated at 0.008mgL−1. The measurements could be performed at a rate of 120 samples per hour with satisfactory precision. The proposed MSFB was successfully applied to analyse 10 plant samples and the results are in agreement with the reference method at a 95% level of confidence.