Supercritical fluid chromatography–supersonic jet spectroscopy: II. Capillary column SFC with a sheath‐flow nozzle

Abstract

Abstract. Supersonic jet spectroscopic detection has been successfully coupled to capillary supercritical fluid chromatography by introduction of the supercritical effluent into a secondary flow of argon, before supersonic expansion of the combined flow through a converging nozzle. At pressures of 6-10 atm, the flowing sheath of argon efficiently carries eluting sample through a 25-p,m nozzle orifice into the supersonic jet. Dead volumes are negligible in this arrangement, and high-resolution fluorescence excitation spectra are obtained. Perylene and benzo[a]pyrene were selectively detected in a standard reference coal tar sample at detection limits of 150 pg and 5 ng, respectively.

The Gulf Oil Spill

“…Raman spectroscopy (UV-RRS), x-ray excited optical luminescence spectroscopy (XEOL), laser-induced molecular fluorescence (LIMF), supersonic jet/laser induced fluorescence (SSJ/LlF), low-temperature fluorescence spectroscopy (LTFS), high-resolution low-temperature spectrofluorometry, low-temperature molecular luminescence spectrometry (LT-MLS), and supersonic jet spectroscopy/capillary supercritical fluid chromatography (SJS/SFC) (Asher 1984; Garrigues and Ewald 1987;Goates et al 1989;Jones et al 1988;Lamotte et al 1985;Lin et al 1991;Popl et al 1975;Richardson and Ando 1977;Saber et al 1991;Vo-Dinh and Abbott 1984;Vo-Dinh 1981;Woo et al 1980). More recent methods for the determination of PAHs in environmental samples include GC-MS with stable isotope dilution calibration (Bushby et al 1993), capillary electrophoresis with UV-laser excited fluorescence detection (Nie et al 1993), and 6.…”

Signal Enhancement by Crossing the Sample Flow at a Small Angle against the Laser Beam in Multiphoton Ionization Mass Spectrometry

“…In order to solve this problem, it is suggested using a technique of supersonic jet expansion: the analyte with a larger molecular weight than the carrier gas of helium can be more efficiently localized at the center part of the jet, thus providing a rod-shaped interaction zone and greater signal enhancement. 16 To investigate the effect of the laser pulse energy on the signal intensity, the mass spectra were measured at a pulse energy of 80 μJ. As shown in Fig.…”

“…To exactly satisfy the requirement provided by the Ministry of Health, Labour and Welfare, Japan, the DL value needs to be further improved 4 fold for octaCDD. This could be achieved with the use of a supersonic jet expansion technique to increase the density of the analyte at the center part of the molecule beam, 16 the use of a pulse-shortening procedure in the process of second harmonic generation, 20 and the use of a fiber laser producing highly repetitive high-average-power subpicosecond pulses. 21,22 Carcinogenic PAH contained in PM2.5 is a subject of intense interest in Japan.…”

Critical assessment: Use of supersonic jet spectrometry for complex mixture analysis (IUPAC Technical Report)

“…This carbonization is minimized by lowering the heating temperature and also by rapid increase in the temperature and decrease in the time of heating. A supercritical fluid containing analytes can be expanded into a vacuum to form a supersonic jet [28][29][30]. Especially, carbon dioxide (CO 2 ) has a low critical temperature (31.0 °C), so that it can be used for the measurement of nonvolatile or thermally labile molecules.…”