title: Electrochemical assay of the antioxidant ascorbyl palmitate in mixed medium.
abstract: Electrooxidation of ascorbyl palmitate (AP) over gold screen-printed electrode (AuSPE) and gold nanoparticles modified graphite (AuNPs/gr) was examined in mixed water-alcohol medium. Voltammetric and amperometric studies showed that: (i) AP oxidation on the AuSPE proceeds at higher potential than on AuNPs/gr; (ii) the current density on AuNPs/gr was 2.4 times higher than on AuSPE; (iii) the linear dynamic range for AuNPs/gr doubled that for AuSPE. At the optimal for AuNPs/gr operating potential (250 mV) the following operational parameters were determined: sensitivity 1.627 ± 0.138 μA mM(-1) mm(-2); linearity up to 500 μM; LOD=5.8 μM. Quantification of the AP content in a real sample - stabilised flaxseed oil, was performed.
authors.affiliation: Department of Chemical Technology, Plovdiv University, 24, Tsar Assen St., BG-4000 Plovdiv, Bulgaria.
authors.forename: Olga
authors.initials: O
authors.lastname: Teneva
authors.affiliation: Department of Physical Chemistry, Plovdiv University, 24, Tsar Assen St., BG-4000 Plovdiv, Bulgaria. Electronic address: nina.dimcheva@uni-plovdiv.net.
authors.forename: Nina
authors.initials: N
authors.lastname: Dimcheva
mesh_terms: D000975:Antioxidants / Q000032:analysis*; D001205:Ascorbic Acid / Q000031:analogs & derivatives* / Q000032:analysis; D055664:Electrochemical Techniques / Q000295:instrumentation / Q000379:methods*; D004566:Electrodes; D006046:Gold / Q000737:chemistry*; D006108:Graphite / Q000737:chemistry*; D008043:Linseed Oil / Q000737:chemistry; D053768:Metal Nanoparticles / Q000737:chemistry*; D010084:Oxidation-Reduction
chemical_list: D000975:Antioxidants; D006046:Gold; D006108:Graphite; D008043:Linseed Oil; D001205:Ascorbic Acid; C031226:6-O-palmitoylascorbic acid
keywords: Antioxidants; Ascorbyl palmitate; Au-nanoparticles; Electrocatalysis; Electrochemistry