Automated sample deoxygenation for improved luminescence measurements

Abstract

Quenching of luminescence by molecular oxygen Is an Inherent limitation In fluorescence and phosphorescence analysis. Consequently, greater analytical sensitivity, as well as lower detection limits, can be achieved by removal of oxygen from the sample prior to luminescence analysis. An automated system for rapid deoxygenation Is described In this paper. This apparatus combines a multiple sampling valve and a membrane barrier to generate a concentration gradient for sample deoxygenation. This automatic, multisample, on-line deoxygenation technique reduces sample handling to a minimum because deoxygenation and luminescence analysis occur within a closed system. The usefulness of this procedure Is discussed In terms of automation, reproducibility, detection limit, deoxygenation efficiency, and applications to a variety of compounds. In addition, potential application of this procedure to other analytical subdsciplines Is also discussed. © 1987, American Chemical Society. All rights reserved.