Ultrafast Gas Chromatographic Separation of Organophosphor and Organosulfur Compounds Utilizing a Microcountercurrent Flame Photometric Detector

Abstract

A microcountercurrent flame photometric detector (microcc-FPD) was adapted and optimized for ultrafast gas chromatographic (GC) separation and detection of organophosphor (OP) and organosulfur (OS) compounds on short chromatographic columns. Air and hydrogen are introduced to the microcc-FPD from opposite directions, creating a hydrogen-rich flame. In this microcc-FPD, combustion takes place between the burner tips without touching them. The separation between the tips and the flame reduces heat loss from the flame to the surrounding environment, resulting in low hydrogen consumption and a compact flame. The microcc-FPD is capable of detecting very narrow (13 ms) chromatographic peaks. An ultrafast GC separation of a group of six OP and OS compounds is achieved within less than 5 s using fast temperature programming of a 0.5-m-long microbore column. Very fast separations are also demonstrated on a 1-m-long microfabricated column consisting of 150-microm-wide, 240-microm-deep channels, etched in a 1.9-cm square silicon chip, covered with a Pyrex wafer, and statically coated with dimethyl polysiloxane. With a hydrogen flow rate of 10 mL/min, the detection limit for OP is 12 pg of P/s and 3 ng of S/s for OS compounds at a signal-to-noise ratio of 2. The coupling of a microfabricated column and a miniature FPD is an important step toward the development of a miniaturized GC-FPD capable of ultrafast detection of low levels of OP and OS compounds.

In situ determination of nerve agents in various matrices by portable capillary electropherograph with contactless conductivity detection

“…Usually, GC [9] and HPLC [10] are coupled to an element specific detector (FPD) [11][12][13] or to a mass spectrometer (MS) [14][15][16] because these detection techniques provide very reliable identification of separated compounds. Each of these techniques has advantages and drawbacks for on-site analysis.…”

Gas Chromatography in Screening of Chemicals Related to the Chemical Weapons Convention

“…The capability of fast GC together with transportable GC/MS for fast analysis has been well demonstrated by Mustacich (37) and Contreras et al (38) An ultrafast GC analysis of dimethyl methylphosphonate and diisopropyl methylphosphonate was achieved within <5 s using very fast temperature programming and a 0.5-m-long microbore column. (39) Comprehensive GC (GC × GC) is based on continuous collection of the effluent from the GC column and periodic reinjection of a small portion of the effluent to a second column of different properties. (40) The major advantage of this technique is improved separation power and it has been successfully used for the analysis of CWC-related chemicals in complex sample matrices.…”

Temperature‐programmed multicapillary gas chromatograph microcolumn for the analysis of odorous sulfur pollutants

“…Kendler et al. demonstrated that GC separation of a group of organophosphor compounds and benzothiophene was achieved by a micro chromatographic column coated with 200–300 nm thick dimethyl polysiloxane (100%) using a microcountercurrent flame photometric detector. Also, Radadia et al.…”

“…The microfabricated column with embedded microposts was described by Sun [12] which can be effectively used in the field of environmental monitoring. Kendler et al [13] demonstrated that GC separation of a group of organophosphor compounds and benzothiophene was achieved by a micro chromatographic column coated with 200-300 nm thick dimethyl polysiloxane (100%) using a microcountercurrent flame photometric detector. Also, Radadia et al utilized a 100 μm wide and 3 m long serpentine micromachined channel filled with the mixture of methyl (95%) + phenyl (5%) polysiloxanes and dicumyl peroxide as stationary phase for the separation of organophosphonate and organosulfur compounds (isopropyl sulfide, chloroethyl methyl sulfide, and isopropyl sulfonyl chloride) utilizing a microcountercurrent flame photometric detector [14].…”