Development of a simple gradient LC-IR interface for the detection of terpenoids from the alpha-pinene-ozone reaction

The development of a simple interface between liquid chromatography and inf rared spectroscopy (LC-IR) using a coaxial sprayer is described for less vo latile analytes. The system consists of a transfer capillary, in which the analytes are transported from the separation column of the gradient-LC to t he outlet of the sprayer. This transfer capillary is coaxially surrounded a t the outlet by a stainless steel sprayer capillary, which is resistively h eated and flushed with nitrogen gas. The samples are sprayed in the manner that the eluent is vaporized by the heated nitrogen when exiting the capill ary, while the analytes are deposited on a moving slide made of infrared tr ansparent material (ZnSe or CaF2). Afterwards the deposited compounds are a nalyzed with an infrared microscope in transmission. First results from rea ction products of the gas phase reaction of alpha -pinene with ozone are pr esented. (C) 2001 Elsevier Science B.V. All rights reserved.