Conventional and Enantioselective GC microfabricated columns versus FSOT columns in the analysis of real world samples in the flavour and fragrance field

Microfabricated columns are highly attractive for gas chromatography because of the number of possible applications in particular for on-site environmental monitoring and in-field analysis. Microfabricated columns are therefore ideal for mobile micro GC instruments because of their small size and low thermal mass affording rapid temperature programming with relatively low power. Silicon micro-electromechanical system (MEMS) technologies are often adopted for microfabricated column preparation. This study adopts etched silicon columns (equivalent, for both pneumatic impedance and chromatographic performance, to a 100 μm dc conventional capillary column) fabricated in silicon substrates that are statically coated with a 0.1-0.2-μm-thick film of different stationary phases. Microfabricated columns 1.68 and 3.20 m long coated with conventional polysiloxane, polyethylene glycol and 30% 2,3 diethyl – 6 t-butyldimethylsilyl-β-cyclodextrin in PS-086. All columns showed an efficiency comparable to that of corresponding conventional columns, i.e. 10000 theoretical plates per meter for SE 52 and 7000 for CD columns respectively using hydrogen as carrier gas. The performance of the resulting microfabricated columns were tested with a conventional GC system and their performance compared to those of conventional columns of the same length and phase ratio and under the same analysis conditions. Comparison was carried out by analyzing a set of essential oils from different plants, volatile fractions and aromas from different food sampled by HS-SPME, and enantiomer separation of racemate standards and real-world samples.