Understanding of peak deterioration in hyphenated speciation systems due to gas–liquid separation in the hydride generation interface

In hyphenated speciation systems with a hydride generation interface one of the processes influencing peak deterioration is gas–liquid separation. A mathematical model was developed to calculate attenuation, signal tailing and resolution loss of HPLC peaks due to gas–liquid separation. It was shown experimentally — using an HPLC–hydride generation–atomic fluorescence spectrometry system for arsenic speciation — that the mathematical model predicts peak deterioration well. This allowed us to study the parameters influencing the deterioration, viz. gas–liquid separation parameters (gas–liquid separator head space volume and purge gas volume flow-rate) and HPLC peak parameters [width (ratio) and resolution] theoretically, simulating HPLC peaks with gaussian functions.