Integration of a microextraction system - Solvent extraction of a Co-2-nitroso-5-dimethylaminophenol complex on a microchip

A newly designed microchannel for solvent extraction was fabricated in a qu artz glass chip and applied to solvent extraction of a Co-2-nitroso-5-dimet hylaminophenol complex. The aqueous solution of Co complex and toluene were introduced into the microchannel, and the Co complex extracted in toluene was detected by thermal lens microscopy (TLM). The Co complex was quickly e xtracted into toluene when the flow was stopped. The observed extraction ti me, ca. 50 s, was almost equivalent to the value calculated using the diffu sion distance and diffusion coefficient. The dependence of the TLM signal o n the concentration of the Co complex showed good linearity in the range of 1 . 10(-7)-1 . 10(-6) M. (C) 2000 Elsevier Science B.V. All rights reserve d.