Chemometrics-assisted excitation–emission fluorescence spectroscopy on nylon-attached rotating disks. Simultaneous determination of polycyclic aromatic hydrocarbons in the presence of interferences

Abstract

This work presents a green and very simple approach which enables the accurate and simultaneous determination of benzo[a]pyrene, dibenz[a,h]anthracene, benz[a]anthracene, and chrysene, concerned and potentially carcinogenic heavy-polycyclic aromatic hydrocarbons (PAHs) in interfering samples. The compounds are extracted from water samples onto a device composed of a small rotating Teflon disk, with a nylon membrane attached to one of its surfaces. After extraction, the nylon membrane containing the concentrated analytes is separated from the Teflon disk, and fluorescence excitation-emission matrices are directly measured on the nylon surface, and processed by applying parallel factor analysis (PARAFAC), without the necessity of a desorption step. Under optimum conditions and for a sample volume of 25 mL, the PAHs extraction was carried out in 20 min. Detection limits based on the IUPAC recommended criterion and relative errors of prediction were in the ranges 20-100 ng L(-1) and 5-7%, respectively. Thanks to the combination of the ability of nylon to strongly retain PAHs, the easy rotating disk extraction approach, and the selectivity of second-order calibration, which greatly simplifies sample treatment avoiding the use of toxic solvents, the developed method follows most green analytical chemistry principles.

Magnetic headspace adsorptive extraction of chlorobenzenes prior to thermal desorption gas chromatography-mass spectrometry

“…However, the main restriction of SPME is the small amount of sorbent present on the fiber, which leads to certain sensitivity problems [11][12][13], thus limiting extraction capacity and, consequently, sensitivity cannot be increased by increasing sample volume. To overcome these problems, there are certain modifications to conventional SPME, based on other configurations of SPME and miniaturization of the conventional solid-phase extraction method such as micro-solid-phase extraction (μ-SPE) [14], stir-cake sorptive extraction (SCSE) [15], rotating-disc sorbent extraction (RDSE) [16], stir-rod sorptive extraction (SRSE) [17], stir-bar sorptive extraction (SBSE) [18], microextraction by packed syringe (MEPS) [19], dispersive μ-SPE (dispersive μ-SPE) [20] and headspace sorptive extraction (HSSE) [11,21].…”

Rapid determination of benzo[a]pyrene by membrane enrichment coupled with solid‐phase constant‐wavelength synchronous fluorescence spectrometry

“…Among the four candidate membranes, the Nylon membrane filter was the best because it showed strong absorbance and low background and contributed the best signal‐to‐background ratio. The ability of the nylon membrane to retain PAHs and other organic compounds, such as benz[a]anthracene and benzo[k]fluoranthene, on its surface has been described in other studies . A Nylon membrane is an appropriate enrichment material for solid‐phase fluorescence determination.…”

“…Nonpolar interactions are expected between hydrophobic PAHs and the methylene chains of nylon. Mass transfer towards the membrane is favored by the fact that PAHs dissolve in the aqueous phase . Therefore, a Nylon membrane filter was selected as the solid‐phase medium for enrichment in the subsequent experiments.…”

Experimental and chemometric strategies for the development of Green Analytical Chemistry (GAC) spectroscopic methods for the determination of organic pollutants in natural waters

“…Recently, and taking advantage of the known ability of the nylon membrane to retain and concentrate PAHs in its surface, benzo[a]pyrene, dibenz[a,h]anthracene, benz[a]anthracene and chrysene were simultaneously extracted from the sample with a nylonbased RDSE device, and then determined by EEFMs, directly recorded on the nylon surface (Cañas et al, 2014). The studied PAHs were quantified with the aid of PARAFAC algorithm at part-per-trillion levels in a very interfering medium.…”