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• A biocompartible covalent triazine framework (CTF) based SPME fiber was developed. • The CTF fiber showed high-coverage capture capacity for in vivo plant metabolites. • A total of 100 plant metabolites were identified using the CTF/GC-QTOF-MS method. • The cabbage possesses different nutrient characteristics in different growth stages. • Significant difference in plant metabolism was found after fipronil exposure. An in vivo solid-phase microextraction (SPME) fiber with high-coverage capture capacity of plant endogenous substances based on the porous covalent triazine framework (CTF) material was developed. The CTF fiber coupled with gas chromatographic quadrupole time-of-flight mass spectrometer (GC-QTOF-MS) analysis was used for monitoring untargeted endogenous metabolites in living Chinese cabbage plants (Brassica campestris L. ssp. chinensis Makino (var. communis Tsen et Lee)). A total of 100 endogenous substances were identified, mainly including aldehydes, ketones, acids, alcohols, phenols, alkanes, alkenes, esters, isorhodanates, nitriles, as well as indole and its derivatives. Using the in vivo metabolites analysis method, Chinese cabbage plants at different growing stages demonstrated significantly statistical differences in plant metabolism. In addition, metabolic dysregulation of Chinese cabbage plants under fipronil pesticide contamination was observed. To summarize, the proposed approach provides a feasible method to capture metabolic information in living vegetables and for risk assessment of pesticide use during agricultural production. [ABSTRACT FROM AUTHOR]

For decades, researches have been involving in improving and optimizing solid-phase microextraction (SPME) technique to fit the growing environmental analysis demand. But it is more significant now to introduce meaningful information into the analysis line instead of improving every step in SPME. Herein, we design a carbon dots (CDs) based SPME platform and report its unique application in selective early screening and sensitive detection of 2-nitroaniline. The fluorescence quenching state of the CDs fiber after extraction could be used to prejudge whether an environmental sample contains 2-nitroaniline exceeding the maximum permitted level (30 μg L−1) regulated by the Chinese Ministry of Environmental Protection or not. Photo-induced electron transfer (PET) is believed to be the primary quenching route that leads to electron transfer from the electron-rich CDs to the electron-deficient analyte. A preliminary in vivo study on Daphnia magna and a 2-nitroaniline assay in environmental water and biofluid samples suggested the safety and the excellent qualitative ability of the proposed platform. As a result, the innovative incorporation of fluorescence sensing and SPME not only achieves the information imbedding of environmental analysis system, but also combines the advantages of two techniques including early visual-screening, reusability (≥50 times), high specificity and excellent quantitative ability (detection limit: 0.011 μg L−1). We believe this study can open new avenues in the field of environmental toxicant monitoring. Image 1 • A carbon dots (CDs) based solid-phase microextraction (SPME) platform was designed. • Nitroaniline's concentration level could be prejudged by the device's fluorescence. • The quenching point of the CDs fiber could be tuned as needed. • 2-Nitroaniline in urine/environmental samples was visual-screened and quantified by GC-MS. [ABSTRACT FROM AUTHOR]

Abstract The exploitation of desired materials with specific properties for water remediation has become an irresistible trend. Generally, materials favorable to the elimination of hazardous contaminants are always beneficial to the detection of these compounds. Nevertheless, few researches combined these two procedures into a treating line. Therefore, a Prussian blue nanoparticles-doped graphene oxide (PBGO) composite was successfully synthesized and prepared as a solid-phase microextraction (SPME) coating for pollutant detection and a three-dimensional (3D) aerogel for contaminant removal in this study. Owing to its highly conjugated structure, abundant oxygen sites and periodical cyano groups, the composite achieved satisfactory enrichment capacity towards specific pollutants. The combination of elimination and determination of organic contaminants by using the PBGO composite not only possessed satisfactory performance but also avoided the separation process and secondary pollution. Finally, the PBGO SPME coating was utilized for the sensitive detection of several hazardous contaminants in environmental water samples with satisfactory recoveries. We think the combination of a PBGO composite with the green sample pretreatment technique (SPME) and pollutant elimination will not only help to facilitate the improvement in analytical fields, but also provide a secondary pollution-free way to explore the adsorption properties of adsorptive materials for environmental contaminants. Graphical abstract Image 1 Highlights • A PBGO composite was synthesized and fabricated as SPME coating and 3D aerogel. • The composite achieved sensitive and selective adsorption ability to specific pollutants. • The composite possessed favorable detection and removal performance towards the pollutants. • The SPME coating was used for detection of contaminants in environmental water samples. [ABSTRACT FROM AUTHOR]

Abstract Analysis of organic pollutants is usually accomplished in centralized laboratories. However, the time-delayed and time-consuming process is insufficient and risky for precisely detection due to the contamination of vials, the losses of analytes during transportation and storage. Herein, a rapid and highly sensitive on-site detection approach was developed without using any vials by coupling an on-site pre-equilibrium solid phase microextraction (SPME) sampling method with a portable gas chromatography mass spectrometer (portable GC-MS), for the determination of three families of persistent organic pollutants (polychlorinated biphenyls, organochlorine pesticides and polycyclic aromatic hydrocarbons). Based on sampling-rate (SR) calibration method, the concentrations of target analytes in aquatic systems could be easily determined. Limits of detection (LODs) in the low parts-per-tillion levels (≤5.25 ng·L−1) were obtained for most of the investigated analytes with a total analysis time only ∼30 min. The proposed on-site detection approach was then successfully applied in the determination of persistent organic pollutants in real aquatic environment. A comparable result obtained by liquid extraction (LE) equipped with laboratorial GC-MS demonstrated the accuracy of the on-site detection method. In general, this study demonstrated a rapid and highly sensitive on-site approach, avoiding any risks of contamination during sampling and analysis, for determination of POPs as well as the potential applications for other organic pollutants in aquatic phase. Graphical abstract Image 1 Highlights • An on-site detection approach is developed based on SPME sampling technique. • The method avoids the contamination, losses, time-delayed and time-consuming issues. • The total analysis time is only ∼30 min. • Lower LODs are obtained comparing with existing on-site detection methods. • A great application potential for other analytes. [ABSTRACT FROM AUTHOR]

Abstract Recent works of designing excellent adsorbents emphasized on the specific surface areas and porosities of the materials. This study presents the influence of morphological modulation on extraction efficiencies of materials for the first time. Sea urchin-like nanoporous carbon (NPC), derived from metal organic framework (MOF), was synthesized and fabricated as solid phase microextraction (SPME) device. The morphological modulated structure of the NPC, with enhanced effective adsorption sites produced by the pointed and sharp edges, could improve the extraction efficiencies of the NPC. Comparing with the unmodulated one, NPC with morphological modulation possessed higher extraction efficiencies (2 flod) as well as accelerated sampling rates (5 flod) on benzene series compounds (BTEX), improving the sensitivity of the sampling method (limits of detection ranged from 0.08 ng L−1 to 0.36 ng L−1). Moreover, it was also the first time that the moisture sensitive MOF-derived NPC was exploited as the SPME adsorbent. In general, this study was expected to be an important advance in broadening the approaches on designing a superior SPME adsorbents not only emphasizing on the specific surface area as well as porosity but also the morphology. Highlights • The morphological modulated MOF-derived nanoporous carbon was synthesized. • Novel SPME fiber was fabricated with the nanoporous carbon and silicone sealant. • The unique morphology remarkably improved extraction performance and sampling rates. • The fiber was employed for the determination of BTEX in real aqueous samples. [ABSTRACT FROM AUTHOR]

Adsorption capacity is the major sensitivity-limited factor in solid-phase microextraction. Due to its light-weight properties, large specific surface area and high porosity, especially tunable pore structures, the utilization of porous organic polymers as solid-phase microextraction adsorbents has attracting researchers' attentions. However, these works mostly concentrated on the utilization of specific porous organic polymers for preparing high-performance solid-phase microextraction coatings. The relationship between pore structures and adsorption performance of the porous organic polymers still remain unclear. Herein, three porous organic polymers with similar properties but different pore distributions were prepared by condensation polymerization reaction of phloroglucinol and terephthalaldehyde, which were fabricated as solid-phase microextraction coatings subsequently. The adsorption capacity of the porous organic polymers-coated fibers were evaluated by using benzene and its derivatives (i.e.,benzene, toluene, ethylbenzene and m -xylene) and polycyclic aromatic hydrocarbons as the target analytes. The results showed that the different adsorption performance of these porous organic polymers was mainly caused by their different pore volumes instead of their surface areas or pore sizes. Finally, the proposed method by using the mesoporous organic polymer coating was successfully applied to the determination of benzene and its derivatives in environmental water samples. As for analytical performance, high pre-concentration factors (74–2984), satisfactory relative recoveries (94.5 ± 18.5–116.9 ± 12.5%), intraday precision (2.44–5.34%), inter-day precision (4.62–7.02%), low limit of detections (LODs, 0.10–0.29 ng L −1 ) and limit of quantifications (LOQs, 0.33–0.96 ng L −1 ) were achieved under the optimal conditions. This study provides an important idea in the rational design of porous organic polymers for solid-phase microextraction or other adsorption applications. [ABSTRACT FROM AUTHOR]

This study presents the preparation and the characterizations of six tri-metal centered metal-organic frameworks (tM-MOFs) as solid-phase microextraction (SPME) adsorbents. Possessing different proportions of Al, Ga and In atoms in their frameworks, the tM-MOF-based SPME coatings exhibited different extraction performance towards the organic pollutants. Extraction results showed that the M4 (Al 0.593 Ga 0.167 In 0.240 (O 2 C 2 H 4 )(h 2 fipbb)) coating exhibited the best enrichment ability among six tM-MOFs. In addition, it showed better extraction efficiency towards the analytes than three single-metal centered MOFs coatings and a commercial polydimethylsiloxane (PDMS) coating. The adsorption process of the M4 coating was physical adsorption and it was mainly affected by the diffusion process of the compound from the sample to the material, which is the same with the adsorption processes of the single-metal centered MOFs coatings. Under optimal conditions (extraction time, 3 min; NaCl concentration, 25% (w/v); desorption temperature, 270 °C; extraction temperature, 30 °C), the M4 coating achieved low detection limits (0.13–0.88 ng L −1 ) and good linearity (5–2000 and 5–5000 ng L −1 ) for benzene series compounds. The repeatabilities (n = 5) for single fiber were between 4.3 and 8.1%, while the reproducibilities (n = 3) of fiber-to-fiber were in the range of 7.9–12.7%. Finally, a M4 coated SPME fiber was successfully applied to the analysis of environmental water samples with satisfactory recoveries (80.8%–119.5%). [ABSTRACT FROM AUTHOR]

Graphene, a novel class of carbon nanostructures, has received great attention as sorbents due to its fascinating structures, ultrahigh specific surface area, and good extraction ability. In this paper, a new type of hierarchical graphene was synthesized through employing a mild and environment-friendly method. Such 3D interconnected graphene own a high specific surface area up to 524 m 2 g −1 , which is about 2.5 fold larger than the graphene, since the synthetic material has interlayer pores between nanosheets and in-plane pores. Then a superior solid-phase microextraction fiber was fabricated by sequentially coating the stainless steel fiber with silicone sealant film and hierarchical graphene powder. Since the novel hierarchical graphene possessed large surface area and good adsorption property, the as-prepared fiber exhibited good extraction properties of the organochlorine pesticides (OCPs). As for the analytical performance, the as-prepared fiber achieved low detection limits (0.08–0.80 ng L −1 ) and wide linearity (10–30,000 ng L −1 ) under the optimal conditions. The repeatability (n=5) for single fiber were between 5.1% and 11%, while the reproducibility (n=3) of fiber-to-fiber were range from 6.2% to14%. Moreover, the fiber was successfully applied to the analysis of OCPs in the Pearl River water. [ABSTRACT FROM AUTHOR]

A series of knitting aromatic polymers (KAPs) were successfully synthesized using a simple one-step Friedel-Crafts alkylation of aromatic monomers and were characterized by transmission electron microscopy (TEM), Fourier transform infrared (FTIR) spectroscopy, and X-ray photoelectron spectroscopy (XPS). Then, as-synthesized KAPs with large surface areas, unique pore structures and high thermal stability were prepared as solid-phase microextraction (SPME) coatings that exhibited good extraction abilities for a series of benzene compounds (i.e., benzene, toluene, ethylbenzene and m -xylene, which are referred to as BTEX) and polycyclic aromatic hydrocarbons (PAHs). Under the optimized conditions, the methodologies established for the determination of BTEX and PAHs using the KAPs-triPB and KAPs-B coatings, respectively, possessed wide linear ranges, low limits of detection (LODs, 0.10–1.13 ng L −1 for BTEX and 0.05–0.49 ng L −1 for PAHs) and good reproducibility. Finally, the proposed methods were successfully applied to the determination of BTEX and PAHs in environmental water samples, and satisfactory recoveries (93.6–124.2% for BTEX and 77.2–113.3% for PAHs) were achieved. This study provides a benchmark for exploiting novel microporous organic polymers (MOPs) for SPME applications. [ABSTRACT FROM AUTHOR]

Mesoporous TiO 2 nanoparticles were synthesized with the hydrothermal method and characterized by powder X-ray diffraction (PXRD) and transmission electron microscope (TEM). Then a superior solid-phase microextraction (SPME) fiber was fabricated by sequentially coating the stainless steel fiber with silicone sealant film and mesoporous TiO 2 powder. The developed fiber possessed a homogeneous surface and a long life-span up to 100 times at direct immersing (DI) extraction mode. Under the optimized conditions, the extraction efficiencies of the self-made 17 μm TiO 2 fiber for six organochlorine pesticides (OCPs) were higher than those of the two commercial fibers (65 μm PDMS/DVB and 85 μm PA fibers) which were much thicker than the former. As for analytical performance, low detection limits (0.08–0.60 ng L −1 ) and wide linearity (5–5000 ng L −1 ) were achieved under the optimal conditions. The repeatabilities ( n = 5) for single fiber were between 2.8 and 12.3%, while the reproducibilities ( n = 3) of fiber-to-fiber were in the range of 3.7–15.7%. The proposed fiber was successfully applied to the sensitive analysis of OCPs in real water samples and four of the six analytes were detected from the rainwater and the lake water samples. [ABSTRACT FROM AUTHOR]

Metal-organic frameworks (MOFs) have received great attention as novel sorbents due to their fascinating structures and intriguing potential applications in various fields. In this work, a MIL-101(Cr)-coated solid-phase microextraction (SPME) fiber was fabricated by a simple direct coating method and applied to the determination of volatile compounds (BTEX, benzene, toluene, ethylbenzene, m -xylene and o -xylene) and semi-volatile compounds (PAHs, polycyclic aromatic hydrocarbons) from water samples. The extraction and desorption conditions of headspace SPME (HS-SPME) were optimized. Under the optimized conditions, the established methods exhibited excellent extraction performance. Good precision (<7.7%) and low detection limits (0.32–1.7 ng L −1 and 0.12–2.1 ng L −1 for BTEX and PAHs, respectively) were achieved. In addition, the MIL-101(Cr)-coated fiber possessed good thermal stability, and the fiber can be reused over 150 times. The fiber was successfully applied to the analysis of BTEX and PAHs in river water by coupling with gas chromatography–mass spectrometry (GC–MS). The analytes at low concentrations (1.7 and 10 ng L −1 ) were detected, and the recoveries obtained with the spiked river water samples were in the range of 80.0–113% and 84.8–106% for BTEX and PAHs, respectively, which demonstrated the applicability of the self-made fiber. [ABSTRACT FROM AUTHOR]

Microplastics (MPs) can adsorb toxic chemicals in biological or environmental matrixes and thus influence their behavior and availability. In order to investigate how the combined pollution of MPs and toxic organic chemical influence microbial growth and metabolism, Escherichia coli (E. coli) was grown in a complex, well-defined media and treated with polystyrene microplastics (PS MPs) and dichloro-diphenyl-tricgloroethane (DDT) at human relevant concentration levels. In vivo metabolites captured by a novel solid phase microextraction (SPME) probe, were used to reflect the metabolic dysregulation of E. coli under different pollution stresses. Results showed that the toxic effect of DDT displayed a distinct dose-dependent phenomenon while the existence of PS decreased the growth and metabolic interference effect of DDT on E. coli. Adsorption results revealed a mechanism that PS weakened the adverse impact of DDT by decreasing its free concentration in the treated culture media. Tricarboxylic acid (TCA) cycle related enzymes activities and antioxidant defense related substances of E. coli also proved the mechanism. The current study is believed to broaden our understanding of the ecotoxicity of MPs with toxic organic chemicals on microorganism. ga1 • DDT displayed a distinct dose-dependent toxicity on E. coli. • Microplastics weakened the toxicity of DDT by decreasing its free concentration. • In vivo metabolites properly reflect the metabolic dysregulation of E. coli. • Degradation path of DDT in E. coli was derived from the detected intermediates. • TCA cycle and antioxidant related enzymes activities varied under contaminations. [ABSTRACT FROM AUTHOR]

At present, researches on various areas have been benefited from the advancement in solid-phase microextraction (SPME) technique, which covers a wide scope of analytes with different properties, facilitates on-site sampling and sample preparation, allows automated operation with high sample throughput, and facilitates long-range monitoring. As the scope of SPME grows, further increases in the specificity, speed and efficiency of this technique are still urgently needed. Application of auxiliary energies is one of the efficient strategies to achieve the aforementioned purpose. This review offers a brief discussion concerning several physical assistive technologies of SPME (e.g. vacuum, ultrasound, microwave, electrical driving force, magnetism, etc.) with respect to targeted or untargeted analysis of different substances in environmental, biological and food samples. Achievements, limitations, and future trends of these applications are also discussed. This review article is believed to be conductive to future applications of auxiliary energy assisted SPME methods in various fields. • Auxiliary energy assisted SPME applications are reviewed. • Vacuum, ultrasound, microwave, electrical driving force and magnetism are introduced. • Advantages and limitations of the current SPME assistive technologies are discussed. • Future recommendations of auxiliary energy assisted SPME are proposed. [ABSTRACT FROM AUTHOR]

In this study, a nitrogen-rich triazine-based porous polymer (NTP) was prepared by the Schiff base mechanism. The NTP contains a high nitrogen content (35.47%) with a larger BET surface area and an adsorption average pore diameter of 860 m2 g−1 and 3.92 nm, respectively. In addition, secondary amines (–C–NH–) and triazine nitrogen (–C N–) in NTP provide a large number of nitrogen active sites, which facilitate the adsorption of triazole pesticides. The synthesized NTP was then used as the solid phase microextraction (SPME) extraction phase material to fabricate the NTP-SPME fiber, which had significantly higher performance in extracting triazole fungicides compared to the commercial fibers (p < 0.05). Subsequently, the bioaccumulation and elimination of three triazole fungicides (myclobutanil, propiconazole, and difenoconazole) in living vegetables were tracked by in vivo SPME sampling and quantified using a gas chromatography quadrupole time-of-flight mass spectrometry. The results showed that the concentrations of myclobutanil, propiconazole and difenoconazole were highest on the first day and showed a trend of first decreasing then equilibrium during bioaccumulation and gradually decreasing during elimination. The highest concentrations of myclobutanil, propiconazole, and difenoconazole in cabbage stems were 997.57 ± 51.42, 841.20 ± 21.42, and 56.82 ± 1.30 ng/g, respectively. In addition, concentrations of difenoconazole were much lower than those of other pesticides throughout the experimental period, which may be related to the difficulty of uptake by cabbage roots due to its strong hydrophobicity and low solubility. This study highlights the application of NTP-SPME for tracking triazole fungicides in living Chinese cabbage plants, which provides valuable information to rationale use of triazole fungicides and their ecological risk assessment. [Display omitted] • A novel SPME fiber was made based on a nitrogen-rich triazine-based porous polymer. • The NTP-SPME fiber has satisfactory extraction performance for triazole pesticides. • In vivo SPME was employed to sample triazole pesticides in living vegetables. • Bioaccumulation and degradation of triazole fungicides were traced in cabbage plants. [ABSTRACT FROM AUTHOR]

3D graphene-carbon nanotubes (G-CNTs) composite with unique morphology and structure was prepared by one-step insertion of CNTs into graphene. Subsequently, the G-CNTs composite as a fiber coating material for solid-phase microextraction (SPME) was fabricated on the surface of a stainless steel wire by direct coating method. The prepared coating was tested by the extraction of benzene homologues (BTEX, benzene, toluene, ethylbenzene and m-xylene). Compared with a commercial polydimethylsiloxane (PDMS) fiber, the home-made coating exhibited higher extraction performance for BTEX, and the reasons were discussed systematically. Under the optimized conditions, the prepared coating coupled with chromatography-mass spectrometry (GC–MS) for the analysis of BTEX exhibited wide linear ranges, low limits of detection (3 S/N) (LODs, 0.59–2.68 ng L −1 ), low limits of quantification (10 S/N) (LOQs, 1.96–8.92 ng L −1 ), good repeatability (3.2–5.5%, n = 6) and reproducibility (3.7–9.1%, n = 3). Finally, the developed method was successfully applied to the analysis of BTEX in environmental water samples with satisfactory recoveries (84.7–108.1%). This study is expected to further the exploration of high-performance SPME coating materials, and broaden the applications of graphene-based materials. [ABSTRACT FROM AUTHOR]

• Metal-organic framework NH 2− MIL101 shows good affinity toward bile acids (BAs). • A core-shell NH 2− MIL101@mSiO 2 based solid-phase microextraction (SPME) probe was design. • The home-made probe shows satisfactory extraction performance and good biocompatibility. • The differences in BA composition in pancreatic cancer patients and cholelithiasis patients were found. In recent years, bile acids (BAs), the important component of bile, were found closely related to the occurrence and development of diseases, therefore, determination of BAs in bile samples is of great significance. However, biological matrix complexity and low concentrations of BAs were still challenging for BA detection in small amount of bile samples. In this work, a core-shell NH 2 -MIL101@mSiO 2 was designed to improve the capture ability of BAs in biological samples, as well as possess good biocompatibility. Subsequently, solid-phase microextraction (SPME) probe of the NH 2 -MIL101@mSiO 2 was coupled with HPLC-MS/MS to establish the analysis method for detecting eight BAs in bile samples. The established method received extraction efficiencies of (30–2143)-fold higher than those of the commercial probes and low limit of detection (LOD ≤ 0.21 ng mL−1). The miniaturization of SPME sampling devices, as well as the low LOD of this work, endowed this method advantage of low consumption of bile samples (30 μL). Based on the proposed method, eight BAs in bile samples of pancreatic cancer patients and cholelithiasis patients were detected successfully. A distinct difference was found in the concentrations of four targeted BAs in bile samples from pancreatic cancer patients and cholelithiasis patients. This work provided a method for quantification of eight BAs in small volume human bile samples, and it could open up a perspective regarding the relationship between BA metabolism and the occurrence of diseases. [ABSTRACT FROM AUTHOR]