US 6,151,113 A · ELSD diffuser

Abstract

An evaporative light scattering detector (1) has a solvent nebuliser (4) through which an atomised spray of solute solvent solution passes, a heated evaporation chamber (5) and a detector system (6). A diffuser trapping device (7), supported by fine wires, is positioned in the evaporation chamber (5) at about two fifths of the height of the chamber from the top. The diffuser trapping device (7) is made from randomly coiled stainless steel ribbon which gives it a large surface area. The detection system (6) is positioned at the bottom of the evaporation chamber through which a beam of collimated light passes and is scattered by the solvent and detected by a light sensitive device (14). The diffuser trapping device (7) aids evaporation of the solvent and prevents large particles from travelling further down the evaporation chamber (5).

Claims11

Dependent claims

An evaporative light scattering detector (ELSD) comprising:

a solvent nebuliser,
a heated evaporation chamber,
a detection chamber into which is directed a collimated light beam normal to the flow of nebulised solvent,
a light sensitive device for detecting scattered light, and
a diffuser-trapping device positioned within said evaporation chamber at a depth of between one third and two thirds of the height of said evaporation chamber and extending substantially across the full diameter of said chamber,
said diffuser-trapping device being formed of a material, and having a porous structure, such that it (i) traps large droplets of said solvent from said nebuliser in said porous structure and, (ii) enhances heat transfer from said heated evaporation chamber to said droplets to enhance their evaporation.

3 more elements

Dependencies are inferred from the claim text.

ELSD diffuser

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ELSD diffuser

Life of this patent

Abstract

Claims11