title: Fast simultaneous determination of BHA and TBHQ antioxidants in biodiesel by batch injection analysis using pulsed-amperometric detection.
abstract: We report the first amperometric method for the simultaneous determination of butylated hydroxyanisole (BHA) and tert-butylhydroquinone (TBHQ) in biodiesel using batch-injection analysis (BIA) coupled to pulsed-amperometry. A sequence of potential pulses was selected in order to detect TBHQ and BHA separately in a single injection step at a glassy-carbon electrode. Samples were diluted in 50% v/v hydroethanolic solution with 0.1 mol L(-1) HClO(4) (supporting electrolyte) before injection using an electronic pipette. The method is highly precise (RSD<1%, n=10), fast (170 injections h(-1)), accurate (recovery between 100 and 110%), presents low detection limits (73 and 75 nmol L(-1) BHA and TBHQ, respectively), and can be easily adapted for on-site determinations.
authors.affiliation: Universidade Federal de Uberlândia Instituto de Química, Av. João Naves de Ávila, Bloco 1D 38.400-902 2121, Uberlândia, MG, Brazil.
authors.forename: Thiago F
authors.initials: TF
authors.lastname: Tormin
authors.forename: Rafael R
authors.initials: RR
authors.lastname: Cunha
authors.forename: Eduardo M
authors.initials: EM
authors.lastname: Richter
authors.forename: Rodrigo A A
authors.initials: RA
authors.lastname: Munoz
mesh_terms: D000975:Antioxidants / Q000032:analysis* / Q000737:chemistry; D056804:Biofuels / Q000032:analysis*; D002083:Butylated Hydroxyanisole / Q000032:analysis* / Q000737:chemistry; D004563:Electrochemistry / Q000379:methods*; D006873:Hydroquinones / Q000032:analysis* / Q000737:chemistry; D007267:Injections / Q000379:methods*; D013997:Time Factors
chemical_list: D000975:Antioxidants; D056804:Biofuels; D006873:Hydroquinones; D002083:Butylated Hydroxyanisole; C018855:2-tert-butylhydroquinone