| Popis: |
A flow-through permittivity measurement device, suitable as a detector in high-performance liquid chromatography, is described. The bridge method is used, with a planar cell of 7-μl capacity, thermostatted with high precision. The detection limit corresponds to a permittivity change of about 0.5·10 −6 . The range is linear up to a sample concentration of about 10%. The contribution to the chromatographic peak width is about 3 μl or 0.12 sec, whichever is greater. Sensitivities for a number of compounds were measured and compared with the differences in the dielectric constants of the sample and eluent. |
