Kinetic determination of propyl gallate in edible and cosmetic oils with sensitized terbium(III) luminescence detection

Abstract

A very fast, selective kinetic method for the determination of propyl gallate is proposed. The analytical parameter used for this purpose is the initial rate of the luminescence reaction between propyl gallate and terbium(Ir1) in the presence of sodium dodecyl sulfate, and is calculated from the slope of a kinetic plot of the luminescence signal as a function of time. The luminescence signal arises from an intramolecular energy transfer between excited propyl gallate and terbium(m), which is followed by the lanthanide emission. Kinetic data can be obtained within only 0.2 s, which entails using the stopped-flow mixing technique but facilitates automation. The calibration graph is linear over the range 0.08-1.0 pg ml-1 propyl gallate and the detection limit is 0.02 pg ml-1. The relative standard deviation is close to 2%. The proposed method was applied to the determination of propyl gallate in various edible and cosmetic oil samples with a mean recovery of 99.1 YO.

Simultaneous Stopped-Flow Determination of Butylated Hydroxyanisole and Propyl Gallate Using a T-Format Luminescence Spectrometer

“…A series of assays were carried out to find a fluorescent chemical system suitable for the determination of BHA and compatible with the spectral features of the terbium(III)-PG system, which allows the sensitive and selective determination of PG (Panadero et al, 1995). Several long-wavelength dyes, namely, oxazine (Nile Blue, Cresyl Violet) and thiazine (Toluidine Blue, Azure A, Azure B) dyes, were assayed with this purpose.…”

“…This process gives rise to a large Stokes shift and narrow and intense emission bands, which avoid or minimize selectivity limitations of luminescence methods. The formation of this chelate was previously applied to the determination of PG (Panadero et al, 1995) in a micellar medium containing sodium dodecyl sulfate (SDS) and Triton X-100. However, as mentioned below, the presence of SDS caused a notable increase on the blank signal of the NB-BHA system, which required a modification of the experimental conditions of the PG system.…”

Design of Lanthanide Complex Probes for Highly Sensitive Time-Resolved Fluorometric Detection Methods and Its Application to Biochemical, Environmental and Clinical Analyses

“…The first description on the use of lanthanide ions as luminescent detection chromophores in liquid chromatography was by DiBella et al [39] for the detection of aromatic ketones and aldehydes. Since then, the method has been extended to a number of other compounds including tetracyclines [40,41], single-stranded nucleic acids [42], nalidixic acid and bleomycins [43], indoles and heterocyclics [44], orotic acid [45,46], steroids such as progesterone and testosterone [47,48], diphacinone [49], fluoroquinolines [50], propyl gallate [51], ochratoxin A and citrinin [52], theopylline [53], and hydrolysis products of dexrazoxane [54]. Inorganic ions have been measured using quenched lanthanide luminescence detection in electrophoretic techniques has also been described [46,48,55].…”

Monoparameter sensors for the determination of the antioxidants butylated hydroxyanisole and n-propyl gallate in foods and cosmetics by flow injection spectrophotometry

“…2,7 Kinetic techniques offer a means to determine synthetic antioxidantsboth individual and mixtures-in foods and cosmetics. 8,9 Flow injection sensors provide a very simple and fast approach, and one that has shown its usefulness for the automatic individual determination of phenolic antioxidants. [10][11][12] The flow approach used in this paper to determine single antioxidants employs such intrinsic properties as the strong UV absorption and transient retention in a solid phase placed into the flow-through cell.…”