High-sensitivity micro-gas chromatography using stochastic injection techniques

In this paper we report an improvement by an order of magnitude of the detection limit of micro gas chromatography systems through the use of m-sequence stochastic injection patterns. Using a sequence length of 127 and using a concentration level of 10 ppb for a BTEX mixture, we obtained an improvement by a factor of 9 in SNR, almost at the theoretical limit of 11 (~√(127)). We also successfully demonstrate that it is possible to simultaneously analyze multiple samples streams in parallel using a single micro-column and the proposed injection technique.