Application of digital-movie-based flow colorimetry to hue-based end point detection of acid-base titration by feedback-based flow ratiometry using universal indicator.

A digital-movie-based flow colorimetry for pH measurement using a universal indicator has been applied to the end point detection of acid-base titrations. A two-channel flow system of feedback-based flow ratiometry, primarily consisting of two peristaltic pumps, a digital microscope-based detector, and a laptop computer, was constructed; a Visual Basic.NET program written in-house was used for automating the analytical processes.