An online fiber-optic UV-visible detector for continuous free-flow electrophoresis

A PC‐controlled, scanning online UV detector for continuous free‐flow electrophoresis (CFFE) was designed to allow for single UV wavelength monitoring across a 1‐D array of 48 longitudinal flow cells interfaced to a CFFE apparatus. In the detection scheme, the UV light is sequentially passed through each of the flow cells. The design integrates online acquisition of absorbance spectra of components separated by CFFE. Benzoic acid standard solutions were used to examine the performance of the detector. Chloroquine diphosphate and 4‐nitrophenol were used as test solutes to determine the detector's ability to distinguish analytes separated in the CFFE.