Direct injection on capillary columns for gas chromatography

Abstract

SummaryDiscrimination may occur when injecting samples onto gas chromatography capillary columns, whereby peak areas for higher boiling point compounds are smaller than they should be compared to lower boiling compounds. This problem is most important in quantitative work on solutes having a wide range of volatility. An all-glass inlet system was used. Injections were made with a 10-1.11 syringe onto a column without an injection point heater and with the column oven about 20°C below the boiling point of the solvent used for the solutes. Discrimination did not occur in a range of CI2 to C36 n-alkanes.

Separation of amino acids in plant tissue extracts by capillary zone electrophoresis with indirect UV detection using aromatic carboxylates as background electrolytes

“…The determination of free amino acids in plant tissue has been achieved by chromatographic methods, including gas chromatography (GC) or gas chromatography-mass spectrometry (GC-MS) and high performance liquid chromatography (HPLC) [3][4][5]. GC or GC-MS methods are based on a variety of derivatization procedures [6][7][8][9], they offer high sensitivity and resolution. However, such complicated derivatization procedures are time-consuming.…”

Selective and Sensitive Determination of Protein and Non-Protein Amino Acids by Capillary Gas Chromatography with Nitrogen-Phosphorus Selective Detection

“…Although NPD-GC is selective and sensitive for nitrogencontaining compounds, there have been few applications to the analysis of amino acids (Butler and Darbre, 1974;Adams et al, 1977;Chauhan et al, 1982;MacKenzie and Holme, 1984;MacKenzie, 1986;Philpott and Van der Merwe, 1991). Therefore, we investigated a selective and sensitive method for the determination of protein and nonprotein amino acids by a combination of convenient derivatization as previously described and an NPD-GC technique.…”

“…Several gas chromatographic (GC) methods for the simultaneous determination of protein and non-protein amino acids have been developed on the basis of the preparation of N(O,S)-heptafluorobutyryl isobutyl esters (Chauhan et al, 1982;MacKenzie and Holme, 1984;Schneider et al, 1985), N,(O,S)-isobutoxycarbonyl (iso-BOC) tert-butyldimethylsilyl (tert-BDMS) derivatives (Oh et al, 1994(Oh et al, , 1995Kim et al, 1996), N(O)-tert-BDMS derivatives (Woo and Lee, 1995) and ethyl chloroformate derivatives (Hušek, 1995;Cao and Moini, 1995). However, some of these methods require anhydrous conditions, high temperatures and long reaction times for the derivatization, and time-consuming GC separation.…”

A Comparative Study of Five Different Methods for the Determination of 3-Methoxy-4-hydroxymandelic Acid in Urine

“…1 -*uo u >ILJ LILI chromatography (GLC) with flame Ionisation detecgether with 3-methoxy-4-hydroxyphenylethyIene-/0 Λ χ , , . /-,' ^x , ,... r u ΟΛ«/ r t .. tlon (8)(9)(10)(11)(12)(13)(14)(15) or electron capture detection (16,17). glycol it accounts for about 80% of the overall turn-."…”