title: Large volume injection in gas chromatography using the through oven transfer adsorption desorption interface operating under vacuum.
abstract: The present work describes a modification of the Through Oven Transfer Adsorption Desorption (TOTAD) interface, consisting of coupling a vacuum system to reduce the consumption of the helium needed to totally remove the eluent for large volume injection (LVI) in gas chromatography (GC). Two different retention materials in the liner of the TOTAD interface were evaluated: Tenax TA, which was seen to be unsuitable for working under vacuum conditions, and polydimethylsiloxane (PDMS), which provided satisfactory repeatability as well as a good sensitivity. No variability was observed in the retention times in either case. Solutions containing organophosphorous pesticides in two different solvents, a polar (methanol/water) and a non-polar (hexane) solvent, were used to evaluate the modification. The vacuum system coupled to the TOTAD interface allowed up to 90% helium to be saved without affecting the performance.
authors.affiliation: Escuela Técnica Superior de Ingenieros Agrónomos, Universidad de Castilla-La Mancha, Campus Universitario s/n, 02071 Albacete, Spain.
authors.forename: Álvaro
authors.initials: Á
authors.lastname: Aragón
authors.affiliation: Escuela Técnica Superior de Ingenieros Agrónomos, Universidad de Castilla-La Mancha, Campus Universitario s/n, 02071 Albacete, Spain.
authors.forename: Rosa M
authors.initials: RM
authors.lastname: Toledano
authors.affiliation: Escuela Técnica Superior de Ingenieros Agrónomos, Universidad de Castilla-La Mancha, Campus Universitario s/n, 02071 Albacete, Spain.
authors.forename: Sara
authors.initials: S
authors.lastname: Gea
authors.affiliation: Escuela Técnica Superior de Ingenieros Agrónomos, Universidad de Castilla-La Mancha, Campus Universitario s/n, 02071 Albacete, Spain. Electronic address: josemanuel.cortes@uclm.es.
authors.forename: José M
authors.initials: JM
authors.lastname: Cortés
authors.affiliation: Facultad de Educación, Universidad de Castilla-La Mancha, Campus Universitario s/n, 02071 Albacete, Spain.
authors.forename: Ana M
authors.initials: AM
authors.lastname: Vázquez
authors.affiliation: Escuela Técnica Superior de Ingenieros Agrónomos, Universidad de Castilla-La Mancha, Campus Universitario s/n, 02071 Albacete, Spain.
authors.forename: Jesús
authors.initials: J
authors.lastname: Villén
keywords: Large volume gas chromatography injection; Polydimethylsiloxane; Tenax; Through Oven Transfer Adsorption Desorption interface; Vacuum