Described is a detector for receiving the eluent from a liquid- or supercritical-fluid chromatograph in which a signal indicative of the presence of an analyte in the eluent is generated by the scattering of light by desolvated particles of the analyte. The detector includes a nebulizer for generating an aerosol from the eluent in a chamber that has a wall in thermal communication with a heat sink. Changes in the temperature of the wall during an analysis of the eluent are reduced by the transfer of heat to the first heat sink.