Vaporizer, capillary column chromatography

A gas chromatograph with a capillary column coupled to a mass spectrometer is an ideal analytical partnership. Effluent from the column has an elevated temperature and the molecules of interest are in a vapor state and ready to enter the ion source. This eliminates the need for desolvation that is required in high-performance liquid chromatography (HPLC)-MS. 

Vapor phase chromatography was performed on an OV 101, fused silica, 20-m capillary column. 

The purity of the Dess-Martin periodinane (2) was assayed by treatment of 2 (1 equiv) with an excess of benzyl alcohol (2 equiv) in methylene chloride (CH2CI2) followed by analysis of the reaction mixture for benzaldehyde by capillary vapor phase chromatography (15-m fused silica capillary column, Durawax DX3 stationary phase, 120°C). After correction for response factors, the purity was established to be >95%. 

Figure 1 Analysis of a standard volatile mixture. Column 80 m X 0.53 mm i.d. SPB-1 (5nm film). Carrier gas helium (flow rate 8.6 ml min ). Oven temperature 40°C (6 min), then to 80°C at 5°C min then to 200°C at 10°C min (run time 26 min). Injection 10pi vapor. Detector sensitivities (fsd) FID, 3.2nA ECD, 64 kHz. Peaks 1, propane 2, FC 12 3, dimethyl ether 4, isobutane 5, butane 6, BCF 7, ethanol 8, acetone 9, 2-prop-anol 10, FC 11 11, FC 113 12, halothane 13, butanone 14, hexane 15, chloroform 16, 1,1,1-trichloroethane 17, carbon tetrachloride 18, trichloroethylene 19, methyl isobutyl ketone 20, 1,1,2-trichloroethane (internal standard) 21, toluene 22, tet-rachloroethylene 23, 2,2,2-trichloroethanol 24, ethyl benzene (internal standard). (Reproduced with permission from Streete PJ, Ruprah M, Ramsey JD, and Flanagan FtJ (1992) Detection and identification of volatile substances by head-space capillary gas chromatography to aid the diagnosis of acute poisoning. Analyst 117 111 1-1127. The Royal Society of Chemistry.)...

Bosboom, J.C. Janssen, H.G. Mol, H.G.J. Cramers, C.A. Large-volume injection in capillary gas chromatography 9. using a programmed-temperature vaporizing injector in the on-column or solvent-vent injection mode. J. Chromatogr. A,... 

The three kinds of solvents (sulfolane, glycerol and dioctyl phthalate) used in this experiment were all analytical reagent. Samples were all analyzed by gas chromatography, and it s model was SP-6800. Besides, the detector was hydrogen flame detector, and the capillary column s model was SE-54, 25 metres long. When samples were analyzed, the vaporizing chamber temperature was 250°C, the detector temperature was 200°C and the column temperature was 90°C. The carrier gas was nitrogen gas, whose pressure was 0.04 MPa. 

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