Preparation of gold nanoparticles and barium coordination polymer doped polypyrrole solid-phase microextraction coating for the detection of nitropolycyclic aromatic hydrocarbons

Solid-phase microextraction - a future technique in pharmacology and coating trends

Traditional sample preparation techniques based on liquid-liquid extraction (LLE) or solid-phase extraction (SPE) often suffer from a major error due to the matrix effects caused by significant co-extraction of matrix components. The implementation of a modern extraction technique such as solid-phase microextraction (SPME) was aimed at reducing analysis time and the use of organic solvents, as well as eliminating pre-analytical and analytical errors. Solid-phase microextraction (SPME) is an innovative technique for extracting low molecular weight compounds (less than 1500 Da) from highly complex matrices, including biological matrices. It has a wide range of applications in various types of analysis including pharmaceutical, clinical, metabolomics and proteomics. SPME has a number of advantages over other extraction techniques. Among the most important are low environmental impact, the ability to sample and preconcentrate analytes in one step, simple automation, and the ability to extract multiple analytes simultaneously. It is expected to become, in the future, another method for cell cycle research. Numerous available literature sources prove that solid-phase microextraction can be a future technique in many scientific fields, including pharmaceutical sciences. This paper provides a literature review of trends in SPME coatings and pharmacological applications.

Exploring the optimal electropolymerization strategy for the preparation of solid-phase microextraction fibers using pyrrole-dopamine copolymers

In-situ electropolymerization of conductive polymers on the surface of stainless-steel substrates is a well-established but promising procedure for the preparation of solid-phase microextraction (SPME) tools. Herein, different electrochemical methods including constant potential (CP), constant potential pulse (CPP), and cyclic voltammetry (CV) were utilized to fabricate SPME fibers by in-situ electropolymerization of pyrrole-dopamine copolymers (PPY/PDA) on the surface of stainless-steel fibers. The coated fibers were characterized and applied for the direct-immersion SPME (DI-SPME) sampling of ultra-trace amounts of plant hormones including abscisic acid (ABA), gibberellic acid (GA3), and indole acetic acid (IAA) in fruit juices, followed by HPLC-UV determination. The results showed that CV electropolymerization is significantly more efficient than the two other methods. The coatings created by the CV method were satisfactorily uniform, adhesive, and durable and exhibited higher extraction performance compared to the CP and CPP procedures. The important experimental variables of the proposed DI-SPME-HPLC method were evaluated and optimized using response surface methodology with a Box-Behnken design. The developed method showed wide-range linearities, spanning from 0.05 to 20μg mL-1 for GA3, and 0.02 to 20μg mL-1 for ABA and IAA. The limits of detection were obtained 0.01μg mL-1 for GA3, and 0.005μg mL-1 for ABA and IAA. The fiber was successfully employed for the simultaneous DI-SPME-HPLC analysis of plant hormones in fruit juice samples.

Conductive Polymer-Based Nanocomposites as Powerful Sorbents: Design, Preparation and Extraction Applications

Conductive polymers as composite materials have been attracted tremendous attention due to their versatile and excellent features such as tunable conductivity, facile synthesis and fabrication, high chemical and thermal stability etc. These characteristics make them versatile and let them being used in numerous fields including microelectronics, optics and biosensors. Throughout the mentioned fields, conductive polymers particularly perform as effective sorbents. Although tremendous efforts have been put into this topic, to the best of our knowledge, a comprehensive up-to-date review on the applications of conductive polymers as efficient sorbents has not been reported. The main objective of this paper is to make a significant contribution to the recent literature toward the synthesis and extraction applications of conductive polymers as efficient sorbents.

Triazine-based covalent organic polymer: A promising coating for solid-phase microextraction

Advancement of novel coating materials for solid-phase microextraction is highly needed for sample pretreatment. Herein, a triazine-based covalent organic polymer was constructed from the monomers of cyanuric chloride and trans-stilbene via the Friedel-Crafts reaction and thereafter used as a solid-phase microextraction fiber coating for the extraction of polycyclic aromatic hydrocarbons and their nitrated and oxygenated derivatives. The newly-developed solid-phase microextraction method coupled with gas chromatography/flame ionization detection gives enhancement factors of 548-1236 and limits of detection of 0.40-2.81 ng/L for the determination of polycyclic aromatic hydrocarbons and their derivatives. The one fiber precision for five replicate determinations of the analytes and the fiber-to-fiber precision with three parallel prepared fibers, expressed as relative standard deviations, was in the range of 4.6-9.4% and 6.2-10.9%, respectively. The relative recoveries of the analytes for environmental water samples were in the range of 88.6-106.4% with the relative standard deviations ranging from 4.0 to 11.7% (n = 5).

Synthesis of hypercrosslinked polymers for efficient solid-phase microextraction of polycyclic aromatic hydrocarbons and their derivatives followed by gas chromatography-mass spectrometry determination

Three novel hypercrosslinked polymers (HCPs) were synthesized via Friedel-Crafts reaction employing 1,3,5-tris(bromomethyl)-2,4,6-trimethylbenzene as alkylating agent, and triphenylbenzene, tetraphenylethylene and p-quaterphenyl as the aromatic units, respectively. The prepared HCPs were applied as solid-phase microextraction coatings for direct immersion extraction of polycyclic aromatic hydrocarbons (PAHs) and their oxygenated and nitrated derivatives in environmental water samples. The key factors affecting the extraction efficiency including extraction time, extraction temperature, stirring rate, ionic strength and desorption conditions, were carefully studied. Coupled with gas chromatography mass spectrometry analysis, a new method for determining PAHs and their derivatives was developed. Under the optimized conditions, the limits of detection (S/N=3) and limits of quantitation (the lowest concentration for quantification) of the method were in the range of 2.5-25.0 and 7.5-75.0 ng L^-1, respectively. The recoveries of spiked samples were in the range of 73.1-118.3% with relative standard deviations less than 13.0%. The developed method was applied for the simultaneous determination of nine PAHs and their derivatives in environmental water samples, showing good accuracy and reliability.