Coupling of large volume injection with flow modulated two-dimensional gas chromatography

Area of Science:

• Analytical Chemistry
• Chromatography

Background:

• Large volume injection (LVI) coupled with comprehensive two-dimensional gas chromatography (GC×GC) offers powerful analysis of complex trace samples.
• Optimizing LVI parameters is crucial for samples with wide boiling ranges.

Purpose of the Study:

• To optimize LVI parameters for GC×GC analysis of samples with a wide boiling range.
• To evaluate injection parameters for peak shape, reproducibility, and peak volume.

Main Methods:

• Utilized a pneumatic modulator based on capillary flow technology for LVI-GC×GC coupling.
• Optimized a split-splitless LVI method using 25 microliters of a 27-compound mixture simulating diesel oil.
• Employed non-polar (Rxi-5ms) and polar (HP-INNOWax) columns for GC×GC separation.

Main Results:

• Solvent vent injection proved unsuitable due to peak splitting and loss of volatile compounds.
• The optimized split-splitless LVI method showed no peak distortion for target compounds.
• Relative peak volumes ranged from 60-120% for all compounds, with 13 compounds showing 80-120%.

Conclusions:

• A robust split-splitless LVI method was successfully developed and optimized for GC×GC.
• This optimized method is suitable for analyzing complex samples with wide boiling ranges using LVI-GC×GC.