A flexible loop-type flow modulator for comprehensive two-dimensional gas chromatography.
The present investigation is focused on a simple flow modulator (FM), for comprehensive two-dimensional gas chromatography (GC×GC). The interface is stable at high temperatures, and consists of a metallic disc (located inside the GC oven) with seven ports, which are connected to an auxiliary pressure source via two branches, to the first and second dimension, to a waste branch (linked to a needle valve) and to an exchangeable modulation loop (2 ports). The ports are connected via micro-channels, etched on one of the inner surfaces of the disc. Modulation is achieved using a two-way electrovalve, connected on one side to the additional pressure source, and to the two metal branches, on the other. An FM enantio-GC×polar-GC method (using a flame ionization detector) was optimized (a 40-μL loop was employed), for the analysis of essential oils. As an example, an application on spearmint oil is shown; the method herein proposed was subjected to validation. Finally, an FM GC×GC diesel experiment was carried out, using an apolar-polar column combination, to demonstrate the effectiveness of the modulator in the analysis of a totally different sample-type.
Dipartimento Farmaco-chimico, Università degli Studi di Messina, Messina, Italy.
Peter Quinto
PQ
Tranchida
Giorgia
G
Purcaro
Alessandro
A
Visco
Lanfranco
L
Conte
Paola
P
Dugo
Peter
P
Dawes
Luigi
L
Mondello
D002849:Chromatography, Gas / Q000295:instrumentation* / Q000379:methods; D004867:Equipment Design; D005742:Gasoline / Q000032:analysis; D006838:Hydrocarbons / Q000032:analysis; D031337:Mentha spicata / Q000737:chemistry; D008956:Models, Chemical; D009822:Oils, Volatile / Q000032:analysis; D015203:Reproducibility of Results
D005742:Gasoline; D006838:Hydrocarbons; D009822:Oils, Volatile