SFC-FID chromatogram

Figure 7.3 SFE-SFC-FID chromatogram of an HDPE/(Irgafos 168, Irganox 1010) extract. After Tikuisis and Dang [112]. Reprinted with permission from T. Tikuisis and V. Dang, in Plastics Additives, An A-Z Reference (G. Pritchard, ed.), Chapman Hall, London, pp. 80-94. (1998) Copyright CRC Press, Boca Raton, Florida...

Figure 6 shows the SFC-FID chromatogram of TNS-9. It exhibits a series of similar multiplets, each consisting of 6 or 7 major peaks or shoulders. Spiking experiments, in which standards were injected... 

Figure 6. SFC-FID chromatogram of Tergitol Nonionic Surfactant-9. Conditions 10 m X 50 urn i.d. X 0.1 tim film DB-17 column, column temperature = lOO C, detector temperature = 70 C, pressure program = 150 atm for 5 min, ramp to 360 atm at 3 atm/min.

Figure 2A. SFC-FID chromatograms of carotenoids separated on DB-17 stationary phase. See Figure 1 for key to compound structures.

Figure 9.19 SFC-FID chromatogram of silylated Maltrin 100. Column, 10 m x 50/im DB-1 mobile phase, CO2 at 89°C [67].

Comparison of FID and FT-IR Detection. Figure 2a shows the flame ionization detector (FID) chromatogram from the capillary SFC separation of the pesticide mixture. This trace was obtained without the SFC/FT-IR flow cell by connecting the capillary separation coluurm directly to the end-of-coluurm restrictor mounted in the FID. This serves as a reference to show the chromatographic separation obtained before connection to the SFC/FT-IR interface. 

Figure 2. a) FID chromatogram from capillary SFC separation of pesticide mixture, b) Gram-Schmidt reconstructed chromatogram of the same separation. 

Figure 9 is the FID chromatogram of a capillary SFC separation of a commercially available pyrethrin extract. The active components are Pyrethrin I at 22.54 min and Pyrethrin II at 23.91 min. Both show good peak shape with no evidence of thermal decomposition. The group of peaks eluting before retention time 19 minutes are from the petroleum based extract matrix. The solvent peak at 8.79 min is methanol. The small peaks at 21.98 and 23.45 minutes are Cinerin I and II respectively. These are related components in the extract having the same structure as pyrethrin except for that the terminal methylene in the pyrethrins is replaced by a methyl group. 

Figure 9. FID chromatogram from capillary SFC separation of pyrethrin extract.

Figure 12.18 LC-SFC analysis of mono- and di-laurates of poly (ethylene glycol) ( = 10) in a surfactant sample (a) normal phase HPLC trace (b) chromatogram obtained without prior fractionation (c) chromatogram of fraction 1 (FI) (d) chromatogram of fraction 2 (F2). LC conditions column (20 cm X 0.25 cm i.d.) packed with Shimpak diol mobile phase, w-hexane/methylene chloride/ethanol (75/25/1) flow rate, 4 p.L/min UV detection at 220 nm. SFC conditions fused-silica capillary column (15 m X 0.1 mm i.d.) with OV-17 (0.25 p.m film thickness) Pressure-programmed at a rate of 10 atm/min from 80 atm to 150 atm, and then at arate of 5 atm/min FID detection. Reprinted with permission from Ref. (23).

FIGURE 4.5 Chromatograms of a-phenylethanol enantiomers nsing (a) SFC and (b) open tubular column GC. Conditions (a) 12 cmx250 p.m ID capillary packed with 5-p.m porous (300 A) silica particles encapsulated with fS-CD polymethylsiloxane (10% w/w) and end-capped with HMDS, 30°C, 140 atm, CO2, FID, 10 cmxl2 p.m ID restrictor, (b) 25 mx250 p.m ID cyano-deactivated capillary cross-linked with fi-CD polymethylsiloxane (0.25 xm df) 130°C He FID. (Reprinted from Wu, N. et al. 2000. J. Microcol. Sep. 12 454-461. With permission.)... 

Figure 1 SFC chromatogram of soybean oil sample. Carbon dioxide mobile phase at 200 C, 10 m x 50 pm i.d. SB-Methyl-100 column, linear density programmed at 0.005 g/mL/min, FID at 375 C. Fatty acid group identification P-Palmitic, O-Oleic, S-Stearic, L-Linoleic, Ln-Linolenic.

Figure 4. SFC chromatograms of celery seed oil. CO2 50 C, FID at 325 C, multi-ramp density programmed. Top chromatogram (A)—4 m X 50 pm i.d. SB-Methyl-100 column bottom (B)—4 m x 50 iTO i d. SB-Biphenyl-30 column.

Figure 2. SFC chromatogram of silylated Maltrin 100. Conditions 10 m X 50/im ID open-tubular column poly (5% phenyl (methylsiloxane stationary phase COj mobile phase 89 °C FID. (Reprinted with permission from Ref 9).

As an example, in natural product analysis, SFC offers perspectives in the analysis of several classes of compounds that present difficulties in either conventional liquid chromatography (LC) or GC. In this area, it is very common that the analytes do not have chromophore groups, thus making difficult the detection through UV-Vis, the most popular HPLC detector. At the same time, several of them are not volatile enough to be analyzed by GC. In this case, the use of SFC with capillary columns and FID detection is a valuable tool. Fig. 3 shows a chromatogram... 

Capillary SFC using carbon dioxide as mobile phase and a FID as detector has been applied to the analysis of several essential oils and seemed to give more reliable quanti cation than GC, especially for oxygenated compounds. However, the separation ef ciency of GC for monoterpene hydrocarbons was, as expected, better than that of SFC. Manninen et al. (1990) published a comparison of a capillary GC versus a chromatogram obtained by capillary SFC from a linalool-methyl chavicol basil oil chemotype exhibiting a fairly good separation by SFC. 

Figure 8.3 (a) SFC chromatogram of a polydimethylsiloxane. Conditions column, 20 m X 50 pm id SB-methyl mobile phase, CO2 at 120 °C with asymptotic density programming, detector FID. (b) SFC chromatogram of epoxy acrylate oligomers. Conditions column 20 m x 50 pm id SB-biphenyl-100 mobile phase, CO2 at 70 C with linear density programming detector FID. Source Author s own files)... 

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