Preparation and evaluation of thermally stable nano‐structured self‐doped polythiophene coating for analysis of phthalate ester trace levels

Abstract

Nano-structured self-doped polythiophene (SPT) electrodeposited in the presence of fluorinated organic acid was applied as a thermally stable conductive polymer-based solid-phase microextraction (SPME) fiber candidate. Quantitative determination of trace levels of phthalate esters including dimethyl phthalate (DMP), diethyl phthalate (DEP), dibutyl phthalate (DBP), and diethylhexyl phthalate (DEHP) was carried out using this novel fiber, coupling with gas chromatography-flame ionization detector (GC-FID). The SPT coating was proved to be stable at high temperatures (∼350°C) with a high extraction capacity and long lifetime (more than 60 times). Improved temperature resistance was obtained by the presence of sulfonated groups in the backbone of polymer. Thermal stability of novel SPT was superior to common polythiophene (synthesized in LiClO(4) ). The extraction procedure was optimized by means of the Taguchi orthogonal array experimental design with an OA(16) (4(5) ) matrix including extraction temperature, extraction time, salt concentration, stirring rate, and headspace volume. The good linearity was obtained for most compounds with correlation coefficients (R(2) ) of between 0.993 and 0.995. The detection limits were lower than 0.12 ng/mL for dimethyl phthalate, DEP, dibutyl phthalate, and diethylhexyl phthalate. The method was successfully applied to the analysis of water samples with the recoveries from 90±1 to 107±1%.

Electrochemical preparation of zinc oxide/polypyrrole nanocomposite coating for the highly effective solid-phase microextraction of phthalate esters

“…When performing experiment with aqueous sample at temperatures of >90°C, the possibility of leaking small amount of water vapor into the needle rises. Expansion of water vapor would produce loss of analyte in the septum purge line and could affect the proper quantitation . Therefore, the higher temperatures >90°C were not tested for practical problems and the extraction temperature was set at 90°C in the subsequent experiments.…”

Development of Novel Solid-Phase Microextraction Fibers

“…Based on the preparation protocol, the fibers were reported with thicknesses ranging from dozens to hundreds micrometers and often possessed rather rough and granulated morphologies. To date, various analytes including organochlorine pesticides [191], phenols [192], phthalate esters [193], antibiotic drugs [194][195][196], and adrenolytic drugs [197], have been analyzed in different sample matrices, even in human plasma [195][196][197] and whole blood [194]. It is notable that Olszowy et al [196] have used several different poly(3-alkylthiophene)-coated SPME fibers to extract linezolid, which showed that the functional groups on the monomeric units could affect the EEs.…”

Nanostructured copper-coated solid-phase microextraction fiber for gas chromatographic analysis of dibutyl phthalate and diethylhexyl phthalate environmental estrogens

“…Phthalates are primarily used as plasticizers in polymeric materials to increase their flexibility though weak secondary molecular interactions with polymer chains . Of the 18 commercial phthalate esters, the share of diethylhexyl phthalate (DEHP) is about 50% .…”

“…The Environmental Protection Agency (EPA) of the United States has regulated the admissible concentration level in drinking water of 6 μg/L for DEHP . The determination of phthalates usually involves capillary GC with flame ionization detection (FID) or MS, and HPLC with diode‐array and MS/MS detection, after sample preparations for enrichments, such as LLE , SPE , SPME , and so on.…”