title: Liquid chromatographic methods to analyze hindered amines light stabilizers (HALS) levels to improve safety in polyolefins.
abstract: A chromatographic method using ultra performance LC with ultraviolet spectrophotometry detection system (UPLC-UV-visible (UV/Vis)) (UPLC, ultra performance LC) was developed to determine Chimassorb 944 and Tinuvin 770, high- and low-molecular mass hindered amine light stabilizers, respectively. The use of a bridge ethylene hybrid-based particles C(18) UPLC column, being compatible with a buffered mobile phase adjusted to pH 11.5, was used to achieve a satisfactory elution of possible non-ionizated units of polymeric Chimassorb 944. In addition, a HPLC with positive ion mode ESI and hybrid linear ion trap (LTQ) Fourier transform (FT) Orbitrap MS detection system (HPLC-UV/Vis-ESI-LTQ(FT)Orbitrap) was used for screening and identification purposes. Reliable determinations of monomeric units of Chimassorb 944 and molecule of Tinuvin 770 were achieved by HPLC-ESI(+)-LTQ FT Orbitrap MS method using scan mode. Quality parameters of UPLC-UV/Vis method were evaluated. Obtained LODs and LOQs were 3.41 and 11.4 mg/L for Tinuvin 770 and 0.83 and 2.78 mg/L for Chimassorb 944, respectively. Satisfactory quality parameters of this chromatography method provided the chance to count on a good tool to know the compliance with legal requirements.
authors.affiliation: Laboratorio de Química, Centro de Investigacións Tecnológicas, Universidad de A Coruña, Ferrol, Spain.
authors.forename: Rosalía
authors.initials: R
authors.lastname: Noguerol-Cal
authors.forename: Jose Manuel
authors.initials: JM
authors.lastname: López-Vilariño
authors.forename: Gerardo
authors.initials: G
authors.lastname: Fernández-Martínez
authors.forename: M Victoria
authors.initials: MV
authors.lastname: González-Rodríguez
authors.forename: Luis F
authors.initials: LF
authors.lastname: Barral-Losada