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Breakpoint chlorination is applied to remove ammonia in water treatment. Trichloramine (NCl

Water utilities encounter unpredictable odor issues that cannot be explained by routine water parameters during spring runoff, even in the summer and fall. Highly water-soluble organics (

N-Nitrosamine disinfection byproducts (DBPs) are a health concern because they are probable human carcinogens. Complex organic nitrogenous compounds, nitrosamine precursors, are largely unidentified in source water. Using stable isotopic labeling-enhanced nontargeted analysis, we identified a natural product N-heterocyclic amine 1-methyl-1,2,3,4-tetrahydro-β-carboline-3-carboxylic acid (MTCCA) in source water. Interestingly, we discovered that chloramination of MTCCA-containing water could produce four nitrosamines: methylethylnitrosamine, N-nitrosopyrrolidine, N-nitrosoanatabine, and N-nitrosoanabasine. Computational modeling and experimental results helped explain potential pathways of nitrosamines generated from chloramination of MTCCA. Further investigations confirmed widespread occurrence of MTCCA in source water and wastewater. Its concentration ranged from high in upstream creeks (23.2-332.2 ng L-1) to low in the river (5.7-37.6 ng L-1) during the 2020 spring runoffs, indicating that sources of MTCCA came from creeks around farms. Analysis of wastewater before and after ultraviolet, as well as microfiltration with subsequent ozonation treatments, showed increased MTCCA after treatments, demonstrating a difficulty to degrade and remove MTCCA in water. This study discovered the extensive presence of MTCCA in source water and wastewater, suggesting that natural N-heterocyclic compounds may serve as a new source of nitrosamine precursors.

Chlorine, chlorine dioxide, and ozone are widely used as disinfectants in drinking water treatments. However, the combined use of different disinfectants can result in the formation of various organic and inorganic disinfection byproducts (DBPs). The toxic interactions, including synergism, addition, and antagonism, among the complex DBPs are still unclear. In this study, we established and verified a real-time cell analysis (RTCA) method for cytotoxicity measurement on Chinese hamster ovary (CHO) cell. Using this convenient and accurate method, we assessed the cytotoxicity of a series of binary combinations consisting of one of the 3 inorganic DBPs (chlorite, chlorate, and bromate) and one of the 32 regulated and emerging organic DBPs. The combination index (CI) of each combination was calculated and evaluated by isobolographic analysis to reflect the toxic interactions. The results confirmed the synergistic effect on cytotoxicity in the binary combinations consisting of chlorite and one of the 5 organic DBPs (2 iodinated DBPs (I-DBPs) and 3 brominated DBPs (Br-DBPs)), chlorate and one of the 4 organic DBPs (3 aromatic DBPs and dibromoacetonitrile), and bromate and one of the 3 organic DBPs (2 I-DBPs and dibromoacetic acid). The possible synergism mechanism of organic DBPs on the inorganic ones may be attributed to the influence of organic DBPs on cell membrane and cell antioxidant system. This study revealed the toxic interactions among organic and inorganic DBPs, and emphasized the latent adverse outcomes in the combined use of different disinfectants.

Amino acids (AAs) are prevalent in source water, particularly during spring run-off. Monitoring of amino acids in source water is desirable for water treatment plants (WTP) to indicate changes in source water quality. The objective of this study was to establish analytical procedures for reliable monitoring of amino acids in source water. Therefore, we examined two different methods, large volume inject (LVI) and solid phase extraction (SPE), for sample preparation prior to HILIC-MS/MS. The LVI-HILIC-MS/MS method can provide fast and sensitive detection for clean samples, but suffers from matrix effects, resulting in irreproducible separation and shortening column lifetime. We have demonstrated that SPE was necessary prior to HILIC-MS/MS to achieve reproducible and reliable quantification of AAs in source water. A natural heterocyclic amine 1-methyl-1,2,3,4-tetrahydro-β-carboline-3-carboxylic acid (MTCCA) was also included in the method to indicate changes in other natural nitrogenous compounds in source water. The SPE-HILIC-MS/MS method was able to achieve limits of detection from 2.6-3400 ng/L for the amino acids and MTCCA with RSDs (n=3) of 1.1%-4.8%. As well, retention times (RT) of the analytes were reproducible with variation less than 0.01 min (n=3) through the entire project. We further applied the SPE-HILIC-MS/MS method to determine AAs in authentic source water samples collected from two drinking water treatment plants (WTPs) during the 2021 spring run-off season. The results support that the SPE-HILIC-MS/MS method does not require derivatization and can provide reliable, accurate, and robust analysis of AAs and MTCCA in source water, supporting future monitoring of source water quality.

Ecotoxicological risks of neonicotinoid insecticides are raising significant concerns, including their potential role in bee population declines. Neonicotinoids are water-soluble, systemic insecticides, and exposure of nontarget organisms such as pollinators occurs mainly through residues in nectar and pollens of flowering plants. To better elucidate the underlying mechanisms for such nontarget exposure, it is highly valuable to develop analytical capabilities for in vivo monitoring of neonicotinoids in live plants. In this study, we developed a novel biomimetic water-swelling solid-phase microextraction (SPME) probe, with limits of detection for neonicotinoids as low as 0.03 ng mL-1, and applied it for in vivo detection of seven neonicotinoids in plant sap. The preparation of this fiber was simple and free of stringent or complex physical-chemical reactions. Equilibrium in neonicotinoid accumulation on the fiber was reached in

As a typical class of emerging organic contaminants (EOCs), the environmental transformation and abatement of preservative parabens have raised certain environmental concerns. However, the remediation of parabens-contaminated water using natural matrixes (such as, naturally abundant minerals) is not reported extensively in literature. In this study, the transformation kinetics and the mechanism of ethylparaben using natural sphalerite (NS) were investigated. The results show that around 63% of ethylparaben could be absorbed onto NS within 38 hr, whereas the maximum adsorption capacity was 0.45 mg/g under room temperature. High temperature could improve the adsorption performance of ethylparaben using NS. In particular, for the temperature of 313 K, the adsorption turned spontaneous. The well-fitted adsorption kinetics indicated that both the surface adsorption and intra-particle diffusion contribute to the overall adsorption process. The monolayer adsorption on the surface of NS was primarily responsible for the elimination of ethylparaben. The adsorption mechanism showed that hydrophobic partitioning into organic matter could largely govern the adsorption process, rather than the ZnS that was the main component of NS. Furthermore, the ethylparaben adsorbed on the surface of NS was stable, as only less than 2% was desorbed and photochemically degraded under irradiation of simulated sunlight for 5 days. This study revealed that NS might serve as a potential natural remediation agent for some hydrophobic EOCs including parabens, and emphasized the significant role of naturally abundant minerals on the remediation of EOCs-contaminated water bodies.

Comprehensive identification of byproducts including intermediate transformation products (TPs) of micropollutants in source water is challenging and paramount for assessment of drinking water quality and treatment technologies. Here, we have developed a nontargeted analysis strategy coupled with computational toxicity assessment to identify indistinguishable TPs including isomers with large differences in toxicity. The new strategy was applied to study the UV treatment of water containing micropollutant 2-mercaptobenzothiazole (2-MBT), and it enabled successful identification of a total of 22 organic TPs. Particularly, the structures of nine new TPs were identified for the first time; in addition, three isomers (P2, P3, and P4) were distinguished from the toxic contaminant 2-hydroxybenzothiazole (2-OH-BT). Computational assessments indicate that estrogenic activity of the three isomers (P2-P4) is higher than that of 2-OH-BT. Mass balance study shows that the 22 organic products accounted for 70% of the 2-MBT degraded, while 30% may degrade to inorganic products. Most TPs are resistant to UV photolysis. Computational toxicity assessment predicted the TPs to increase inhibition of human thyroperoxidase activity although they have lower aquatic toxicity compared to original 2-MBT. This study emphasizes the importance of monitoring the 2-MBT photodegradation products and the overall toxicity of finished water whose production included a UV light-based treatment process.

Exploring the presence of polycyclic aromatic hydrocarbons (PAHs) in aquatic environment is an important task. Metal-organic frameworks (MOF) are commonly used as sorbents for enriching PAHs but their crystal synthesis, sorbent preparation and robustness remain challenging. In the present study, under mild conditions, a novel sheathed MOF fiber coating was fabricated via in situ heteroepitaxial growth of copper-2,5-diaminoterephthalate (Cu-DAT) crystals and subsequent polyimide (PI) sheath. The copper hydroxide nanotubes were first synthesized on the copper wire to provide a substrate for further in situ heteroepitaxial Cu-DAT growth, and the coating was then sheathed with PI via a simple dip-coating procedure. The well-ranged copper hydroxide nanotubes, the unique adsorption property of Cu-DAT, and the PI sheath, the prepared fiber all contributed to a successful solid-phase microextraction (SPME) device for detecting PAHs. Results demonstrated that the SPME methods using the novel fiber possessed great sensitivity, wide linear range, good reproducibility, and the robustness was significantly improved with PI sheath. The novel SPME material was successfully applied for detection of PAHs in river water samples and in vivo detection of PAHs in fish dorsal muscle. In general, this study explored an effective and convenient method to prepare high-efficient MOF-based SPME fiber for PAHs analysis in complex environmental water samples and living organisms via in situ growth and polymer sheath.

Conflicts often exist between the use of pesticides for public health protection and organic farming. A prominent example is the use of insecticides for mosquito control in rice fields designated for organic farming. Rice fields, with static water and other conducive conditions, are favorable mosquito habitats. Best management practices are urgently needed to ensure the integrity of organic farming while addressing the need for public health protection. In this study, we evaluated aerial ultra-low-volume (ULV) applications of two classes of mosquito adulticides, pyrethrins and organophosphates, and their deposition and residues on rice plants throughout an active growing season in the Sacramento Valley of California. Frequent applications of pyrethrin synergized with piperonyl butoxide (PBO) and rotating applications of synergized pyrethrins and naled, an organophosphate, were carried out on two large blocks of rice fields. Aerial ULV application of either synergized pyrethrins or naled was able to generate uniform droplets above the fields with high efficacy for mosquito control. Rice leaf samples were collected before and after a subset of applications, and rice grains were sampled at harvest. Frequent applications of synergized pyrethrins resulted in some accumulation of the synergist PBO on rice leaves, but pyrethrins and naled dissipated rapidly from the leaves after each application with no noticeable accumulation over repeated applications. At harvest, no detectable residues of the pesticides or PBO were found in the rice grains. The absence of pesticide residues in the rice grains at harvest suggested that the ULV aerial application led to deposition of only very low levels of residues on rice plants during the growing season. When coupled with the short persistence and/or poor mobility of the insecticides, such applications resulted in negligible pesticide residues in rice grains.

Tetrodotoxin (TTX) is one of the most toxic substances of non-protein in nature. In present study, a rapid and sensitive method based on in vivo solid-phase microextraction (SPME) coupled to liquid chromatography tandem mass spectrometry (LC-MS/MS) was developed to detect the endogenous TTX in pufferfish (Fugu). Fiber evaluation experiments demonstrated that, compared with the commercial PDMS and PA fibers, the home-made electrospun PS@PDA-GA fibers exhibited much better extraction performance towards to TTX in water (120 times and 20 times, respectively), under the optimized conditions. Then, the home-made SPME fibers were employed to extract TTX in spiked homogeneous fish muscle samples, and a LC-MS-MS was used for the analysis. The reproducibilities (RSDs of inter and intra fiber were 12.1%, and 7.9% respectively), linear range (10-1000ngg-1, R2=0.9963) and sensitivity (the LOD was 2.3ngg-1) of the method were found to be excellent and satisfactory for further in vivo experiments. Especially the LOD of the established method is lower than the National Standard Method of China (GB/T 23217-2008, LOD 50ngg-1). Subsequently, the method was successfully applied to detect the TTX in the dorsal muscle of living pufferfish, and the accuracy was verified with traditional liquid extraction (LE) method. In general, this is the first study to detect TTX in pufferfish by in vivo sampling method, which provided a promising alternative method for the studies of TTX, and also advanced the implementation of SPME for more in vivo studies.

Nanostructured materials have great potential for solid phase microextraction (SPME) on account of their tiny size, distinct architectures and superior physical and chemical properties. Herein, a core–shell TiO2@C fiber for SPME was successfully fabricated by the simple hydrothermal reaction of a titanium wire and subsequent amorphous carbon coating. The readily hydrothermal procedure afforded in situ synthesis of TiO2 nanowires on a titanium wire and provided a desirable substrate for further coating of amorphous carbon. Benefiting from the much larger surface area of subsequent TiO2 and good adsorption property of the amorphous carbon coating, the core–shell TiO2@C fiber was utilized for the SPME device for the first time and proved to have better performance in extraction of polycyclic aromatic hydrocarbons. In comparison to the polydimethylsiloxane (PDMS) and PDMS/divinylbenzene (DVB) fiber for commercial use, the TiO2@C fiber obtained gas chromatography responses 3–8 times higher than those obtained ...

Detection of pollutants in animals and plants is crucial for understanding their capability and assessing the risk they pose to the environment and ecology. At present, the research on this area has been benefited from the advances in in vivo solid-phase microextraction (SPME), which reduces the sacrifice of animals and plants, facilitates on-site sampling and sample preparation, enables detection of unstable analytes, and facilitates long-term monitoring. This study summarizes the recent applications of in vivo SPME in detecting pollutants in animals and plants. The samplers, quantification methods, and various cutting-edge applications are discussed in detail. The future trends of using in vivo SPME in environmental analysis are also discussed.

In this study, the phase I metabolism of fenthion was monitored in three common vegetables in different chamber situations via an in vivo solid-phase microextraction method. The phase I metabolic pathways of fenthion were evaluated based on the in vivo monitoring results and their comparisons among the chamber situations. Enzyme catalysis was found to play a basic and dominant role, whereas light catalysis could promote subsequent transformations that were difficult for enzyme catalysis. Moreover, according to the concentrations of the metabolites and their toxicity, the total concentrations and total toxicity weighted concentrations were calculated to reveal actual residual levels. The relative total and weighted exposure potency values were calculated to account for the fact that only the parent pesticide was considered in the diet exposure risk assessment. In result, both total and weighted approaches indicated a much higher exposure risk. Present study uncovered the potential pesticide exposure risk associated with phase I metabolism and highlighted the toxicity weighted approach, both of which more realistically reflect the exposure risk than the parent compound concentration does. In general, this study may facilitate further illustrating the phase I metabolism of ubiquitous agricultural pesticides, and provide a more realistically understanding of their exposure risk.

An in vivo uptake and elimination tracing study based on solid phase microextraction (SPME) was conducted to investigate the accumulation, persistence and distribution of organochloride pesticides (OCPs) and organophosphorus pesticides (OPPs) in malabar spinach (Basella alba L.) plants. Uptake and elimination of the pesticides were traced in leaves, stems and roots of living malabar spinach plants. Root concentration factor (RCF), distribution concentration factor (DCF) and transpiration stream concentration factor (TSCF) were calculated based on the in vivo tracing data. The tracing data showed that the OCPs were much more accumulative and persistent than the OPPs in roots, while they were similarly accumulative and persistent in leaves and stems. RCF values of the OPPs or OCPs were likely to increase with the increase in LogKow values except fenthion. Obtained DCF values indicated that OPPs and OCPs were more accumulative in the organs containing more lipids. TSCF values showed that the translocation of OPPs and OCPs from roots to foliage was firstly dependent on the hydrophobicity of the compounds, but also significantly affected by the water solubility. This is the first study of generating RCF, DCF and TSCF data in living plants by in vivo sampling method, which provides a foundation to promote the application of in vivo SPME and improve understanding of contaminant behaviors in living plants.

In this study, the biocompatible copolymer Poly(lactic acid-co-caprolactone) (PLCL) doped with sulfonated γ-Al2O3 nanoparticles was used for electrospun on stainless wires. The electrospun fibers were further sheathed by the self-polymerization of norepinephrine, a catecholamine found both in neurotransmitters and mussel adhesive proteins, to improve the surface hydrophilicity and provide a smooth bio-interface. The modified electrospun fibers on stainless wires were developed as novel custom-made solid-phase microextraction (SPME) fibers. These fibers exhibited much higher extraction efficiency compared to the polydimethylsiloxane (PDMS) fibers, especially to the sulfonamides. The custom-made SPME fibers also showed excellent stability with the relative standard deviations (RSDs) of intra-fiber ranged from 1.98% to 9.86% and RSDs of inter-fiber ranged from 4.36% to 15.6%. Moreover, these fibers were also demonstrated to be anti-biofouling and suitable for in vivo sampling. The custom-made SPME fibers were successfully applied to determine the Pharmaceutical concentrations in living fishes and vegetables. The accuracies were verified by the comparison with liquid extraction and the sensitivities were demonstrated to be satisfying with the limits of detection (LODs) ranged from 0.16ng/g to 5.35ng/g in fish muscle and 0.02ng/g to 8.02ng/g in vegetable stem.

A novel solid-phase microextraction (SPME) fiber was prepared by gluing poly(diallyldimethylammonium chloride) (PDDA) assembled graphene oxide (GO)-coated C18 composite particles (C18@GO@PDDA) onto a quartz fiber with polyaniline (PANI). The fiber surface coating was sequentially modified with bioinspired polynorepinephrine, which provided a smooth biointerface and makes the coating suitable for in vivo sampling. The novel custom-made coating was used to extract acidic pharmaceuticals, and high-performance liquid chromatography tandem mass spectrometry (HPLC-MS/MS) was employed for analysis. The custom-made coating exhibited a much higher extraction efficiency than the previously used commercial polydimethylsiloxane (PDMS) and polyacrylate (PA) coatings. The custom-made coating also possessed satisfactory stability (the relative standard deviations (RSDs) ranged from 1.60% to 10.3% for six sampling-desorption cycles), interfiber reproducibility (the RSDs ranged from 2.61% to 11.5%), and resistance to matrix effects. The custom-made fibers were used to monitor the presence of acid pharmaceuticals in dorsal-epaxial muscle of living fish, and satisfactory sensitivities (limits of detection ranged from 0.13 ng/g to 7.56 ng/g) were achieved. The accuracies were verified by the comparison with liquid extraction. Moreover, the novel fibers were successfully used to monitor the presence of acidic pharmaceuticals in living fish, which demonstrated that the custom-made fibers were feasible for possible long-term in vivo continuous pharmaceutical monitoring.

In vivo solid-phase microextraction (SPME) sampling method coupled with gas chromatography-mass spectrometry (GC-MS) analysis was employed to trace the uptake and elimination of organophosphorus pesticides (OPPs) in two kinds of edible plants, cabbage (Brassica parachinensis) and aloe (Barbadensis). The metabolism of fenthion in aloe was also investigated by the liquid chromatography tandem mass spectrometry analysis (LC-MS/MS) to understand the fate of OPPs in living plants better. Transpiration stream concentration factor (TSCF) and depuration rate constants of the OPPs in living plants were obtained therein. The health risk of the OPPs treated aloe was estimated by the maximum residue limit (MRL) approach, and it revealed that the OPPs were rather safe for their fast degradable property. However, peak concentration of fenthion-sulfoxide was found to exceed the MRL and was higher than that of the parent fenthion, which indicated the potential risk of pesticide metabolites. This study highlighted the application of in vivo SPME for contaminant tracing in different living edible plants. The in vivo tracing method is very convenient and can provide more data to evaluate the risk of different pesticides, which are very important for the safety of agriculture production.

Carbohydrates are known to be involved in a wide range of biological and pathological processes. However, due to the presence of multiple hydroxyl groups, carbohydrate recognition is a particular challenge. Herein, we reported an ultrasensitive solid-phase microextraction (SPME) probe based on phenylboronic acid (PBA) functionalized carbon nanotubes (CNTs) for direct in vitro or in vivo recognition of carbohydrates in biofluids as well as semi-solid biotissues. The coating of the proposed probe possessed a 3D interconnected porous architecture formed by the stacking of CNTs. As a result, the binding capacity toward carbohydrates was excellent. The proposed approach was demonstrated to be much superior to most carbohydrate sensors, including higher sensitivity, wider linear range, and excellent qualitative ability in multi-carbohydrate systems. Thus, this approach opens up new avenues for the facile and efficient recognition of carbohydrates for important applications such as glycomics.

As emerging contaminants, synthetic musks (SMs) cause worldwide concern due to their bioaccumulation in biota. However, the environmental fates of SMs in biota are poorly understood. Here, for the first time, the uptake and elimination behaviors, as well as the transferable capacities, of SMs in living edible biota (fish and aloe) were revealed. Fish muscle was approximately 100–2000 times more efficient in accumulating SMs than was aloe leaf, and nitro musks showed a higher bioaccumulation potential than did polycyclic musks in biota. In addition, the transferable capabilities of SMs by root uptake in aloe were poor. This investigation also showed that both nitro musks and polycyclic musks that accumulated in biota exhibited excellent elimination rates in clean water, and the elimination rates were greater than 78% and 80% in fish (3 d) and aloe (2 d), respectively. Furthermore, the calculated results suggest that SMs might act as chemosensitizers and enhance the accumulation of normally excluded toxicants in biota in a real aquatic environment.

Driven by the development of mass spectrometry (MS), omics strategies become powerful tools for comprehensive analysis of organics in water. Various separation and ionization techniques have been developed in recent years for MS based omics analysis of water to achieve better resolution, sensitivity, and throughput. Additionally, advances in computer algorithms and enlargement of online databases have enabled batch processing of massive amounts of MS data, drastically shortening analysis time and increasing compound coverage. With such improvements, omics screening of organics in water becomes feasible, leading to high throughput analysis that can tentatively identify thousands of unknowns in a single run. Targeted analysis utilizes existing information of selected compounds to narrow scan ranges, collect further data on selected analytes and quantify these target compounds. Herein, we review recent advances in MS-based omics strategies integrating nontargeted and targeted techniques for analysis of organics in water and discuss existing challenges and future trends.

In recent years, pharmaceuticals have received increasing attentions because of their potential risks to the environment, but researches focusing on their impacts on defense system of living plants are still lacking. As an important class of phytohormones, jasmonates play crucial roles in plant defense system against environmental stress. In order to investigate the effect of pharmaceuticals uptake on endogenous jasmonates, an in vivo solid phase microextraction (SPME) method was established to simultaneously detect and monitor both pharmaceuticals and jasmonates in living plants. The proposed method exhibited wide linear ranges, high sensitivity (limits of detection ranging 0.0043–0.035 ng g−1 for pharmaceuticals and 0.091–0.22 ng g−1 for jasmonates, respectively), and satisfactory reproducibility (relative standard deviation of intrafiber ranging 4.2%–8.6% and interfiber ranging 5.2%–8.2%, respectively). Subsequently, this method was successfully applied to track the concentrations of each pharmaceutical and corresponding jasmonates in living Malabar spinach plants (Basella alba. L) exposed to three common pharmaceuticals (i.e. gemfibrozil, mefenamic acid and tolfenamic acid) over 15 days. In result, all pharmaceuticals appeared to trigger intensive biosynthesis of jasmonic acid (JA) (3.1–9.4 times of control) while reduced the concentration of methyl jasmonate (MeJA) (18.3%–38.1% of control). We inferred that uptake of pharmaceuticals acted as an abiotic stress and stimulated the plant defense response because of the variation of jasmonates. To the best of our knowledge, this is the first study applying SPME to detect and track both pharmaceuticals and phytohormones in living plants, which not only provided a glimpse to the adverse effect of pharmaceuticals on plants as well as the regulation of endogenous jasmonates, but also set a promising template for future in vivo analysis of xenobiotics and plant endogenous substances.

In recent years, great concerns have been raised about salicylic acid (SA) and its derivatives as plant regulators. Therefore, precise determination of the distribution of SAs in the living plants is necessary for not only fundamental researches but also the regulating mechanisms. In this study, a custom-made solid phase microextraction (SPME) fiber based on diallyl dimethyl ammonium chloride-assembled graphene oxide-coated C18 composite (C18@GO@PDDA) was proposed for in vivo detection of salicylic acid, acetylsalicylic acid (ASA), 4-methyl salicylic acid（4-SA）and 3-methyl salicylic acid (3-SA) in aloe plants. Under the optimized conditions, the analytical performance evaluated in homogenized aloe plant tissues exhibited low detection limits (1.8–2.8 μg g−1), wide linear ranges (10–5000 μg g−1), and satisfactory reproducibility (relative standard deviations less than 8.4% and 9.3% for inter-fiber and intra-fiber assays, respectively). Under cadmium stress, the developed method was applied for the in vivo tracing of four salicylic acids in aloe plants. A 48-h in vivo tracing revealed that salicylic acids were involved in the pathway of cadmium stress tolerance. To our best knowledge, it is the first effort to realize the in vivo analysis of SA and its derivatives in plants, and it has a made a great step forward in the area of plant hormone analysis.

Decreasing the tedious sample preparation duration is one of the most important concerns for the environmental analytical chemistry especially for in vivo experiments. However, due to the slow mass diffusion paths for most of the conventional methods, ultrafast in vivo sampling remains challenging. Herein, for the first time, we report an ultrafast in vivo solid-phase microextraction (SPME) device based on electrosorption enhancement and a novel custom-made CNT@PPY@pNE fiber for in vivo sampling of ionized acidic pharmaceuticals in fish. This sampling device exhibited an excellent robustness, reproducibility, matrix effect-resistant capacity, and quantitative ability. Importantly, the extraction kinetics of the targeted ionized pharmaceuticals were significantly accelerated using the device, which significantly improved the sensitivity of the SPME in vivo sampling method (limits of detection ranged from 0.12 ng·g–1 to 0.25 ng·g–1) and shorten the sampling time (only 1 min). The proposed approach was succe...

Sensitivity and selectivity of the solid phase microextraction (SPME) in analysis are mostly determined by the coating material of the fiber used. Graphene oxide (GO) has attracted great attention because of its large specific surface area, rich oxygen functional groups, good dispersibility in aqueous solution and high reactivity. However, the low thermal stability of the functional groups limits the wide application of GO in SPME coating design. Highly cross-linked polyoxyethylene (POE) is a substrate widely used for composite material construction, which could significantly improve the thermal stability, water resistance as well as biocompatibility of the functional materials. In this study, we incorporated GO with highly cross-linked POE as a novel fiber coating material for SPME through the gluing approach. The obtained fiber possessed a wrinkled shape surface, which could increase the accessible surface area. In addition, the thermal and chemical stability of the fiber coating were also improved, rendering the fiber rigid enough for more than 100 repetitive extraction cycles. The performance of this developed SPME method for phenols was evaluated by headspace extraction of phenols in aqueous samples. Compared with three commercial fibers, the home-made fiber showed excellent extraction efficiencies towards phenols. Under the optimized conditions, it showed low detection limits (0.12–1.36 ng· L−1), good precision ( 99%), as well as good enrichment efficiencies (enrichment factors (EFs), 172–1752). Furthermore, the method was successfully applied in simultaneous analyses of five phenols for real water samples with satisfactory recoveries (81–113% for the Pearl River samples).

Fluoroquinolones (FQs) are a group of antimicrobial agents that have been widely used for therapeutic purposes in clinical medicine for human and veterinary diseases, as well as in aquaculture production. Their residues, however, may survive in foods of animal origin, thus causing health risks for human. In this study, a rapid and sensitive method based on in vivo solid-phase microextraction (SPME) coupled with liquid chromatography-tandem mass spectrometry (LC-MS/MS) was developed to detect the residues of five FQs in cultured puffer fish (Takifugu obscurus). In vitro fiber evaluation experiment demonstrated that, compared with the thicker polydimethylsiloxane (PDMS) coating (165µm), the custom-made biocompatible C18-PAN fibers (45µm) exhibited much higher extraction efficiencies towards FQs (approximately 9-31 times). The custom-made C18-PAN coating also possessed excellent reproducibility in fish muscle with the intra-fiber relative standard deviations (RSDs) ranging from 11.2% to 14.3% (n = 6) and inter-fiber RSDs ranging from 13.1% to 16.1% (n = 6), which was suitable for in vivo sampling. The custom-made SPME fibers were subsequently applied to determine fluoroquinolones in dorsal-epaxial muscle of living puffer fish. The accuracies were verified through the comparison with traditional liquid extraction (LE) method, and the sensitivities were demonstrated to be satisfying with the limits of detection (LODs) ranging from 0.3ngg-1 to 1.5ngg-1. In general, this study presented a convenient and high-efficient method to determine fluoroquinolones in puffer fish by in vivo sampling.

Although nanotechnology has offered effective and efficient solutions for environmental remediation, the full utilization of sustainable energy and the avoidance of secondary pollution are still challenges. Herein, we report a two-step modification strategy for TiO2 nanoparticles by first forming a thin, surface-adherent polydopamine (PDA) shell onto the nanoparticles and then assembling core–shell nanoparticles as a photodegradation coating. The composite coating modified from TiO2 could not only realize the highly efficient utilization of photons from the visible region but also avoid the secondary pollution of nanoparticles during application. Additionally, improvements in the adsorption ability after modification greatly facilitated the photocatalytic process of the modified materials. A preliminary in vivo study on Daphnia magna and a wastewater treatment experiment suggest that treatment with the composite coating can effectively eliminate fluorene and significantly reduce its lethality. We believe ...

The aim of this study was to explore donor risk factors that predict the poor outcomes after living donor kidney transplantation.We retrospectively analyzed our 219 living donor kidney transplantations collecting donor age and gender, graft glomeular filtration rate (GFR), human leukocyte antigen (HLA) typing, recipient age and gender, acute rejection episodes chronic rejection, and 1-year serum creatinine level. Patient and graft survivals were calculated using the Kaplan-Meier analysis. Independent donor risk factors affecting graft survival and 1-year serum creatinine level were analyzed using Cox regression and logistic regression.One-, 3-, 5-year patient and graft survivals were 98.6%, 98.1%, and 97.4% and 97.7%, 95.0%, and 92.2%, respectively. Acute rejection rate was 12.8%, and chronic rejection, 4.1%. If donor age was over 50 years, there were significantly increased incidences of acute and chronic rejection (χ(2) were 5.385 and 5.039; P.05). Univariate analysis showed donor age50 years, graft GFR35 mL/min, female to male, HLA mismatch3 loci to be risk factors for an abnormal 1-year serum creatinine. Logistic multivariate regression revealed donor age50 years, female to male, and graft GFR before transplant35 mL/min to be independent risk factors for an abnormal 1-year serum creatinine level (odds ratio values 5.928, 2.489, and 6.993, respectively; P.05). Cox multivariate regression demonstrated that graft GFR before transplant35 mL/min was an independent risk factor for long-term graft survival (relative risk value = 6.984; P = .004).Older donor, female to male, and insufficient graft GFR before transplantation are predictive factors for poor outcomes of living donor kidney transplantations.

Purpose The purpose of this study was to explore the outcomes and risk factors for hepatitis B virus (HBV) reactivation after kidney transplantation in occult HBV carriers, who are hepatitis B surface antigen (HBsAg) seronegative and hepatitis B core antibody (HBcAb) seropositive before kidney transplantation. Methods We retrospectively analyzed 322 occult HBV carriers who received kidney transplantation in our hospital from January 1998 to June 2008. HBsAg and HBV DNA were routinely checked for diagnosis of HBV reactivation. Results Our results showed that 15 cases (4.7%) of occult HBV carriers had HBV reactivation after kidney transplantation. Kaplan–Meier analysis showed that 1-, 3-, 5-, and 10-year patient survival was 86.7%, 79.4%, 72.2%, and 65.0%, respectively, in the HBV reactivation group, and was 96.1%, 93.8%, 91.5%, and 84.5%, respectively, in the non-HBV reactivation group (log-rank 4.12, P = 0.042). Graft survival showed no difference between these 2 groups (P > 0.05). The incidences of impairment of liver function, liver function failure, hepatocellular carcinoma, and acute rejection were significantly higher in the HBV reactivation group compared with the non-HBV reactivation group (P 60 years) and using anti-T-cell antibodies were independent risk factors for HBV reactivation after kidney transplantation, while being hepatitis B surface antibody (HBsAb) seropositive and using lamivudine prophylaxis could protect occult HBV carriers from HBV reactivation after kidney transplantation (P

A biocompatible probe for specific glucose recognition is based on photoinitiated boronate affinity-molecular imprinted polymers (BA-MIPs). The unique pre-self-assembly between glucose and boronic acids creates glucose-specific memory cavities in the BA-MIPs coating. As a result, the binding constant toward glucose was enhanced by three orders of magnitude. The BA-MIPs probe was applied to glucose determination in serum and urine and implanted into plant tissues for low-destructive and long-term in vivo continuous glucose monitoring.

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 m2 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.

Elucidating the availability of the bound analytes for the mass transfer through the diffusion boundary layers (DBLs) adjacent to passive samplers is important for understanding the passive sampling kinetics in complex samples, in which the lability factor of the bound analyte in the DBL is an important parameter. In this study, the mathematical expression of lability factor was deduced by assuming a pseudo-steady state during passive sampling, and the equation indicated that the lability factor was equal to the ratio of normalized concentration gradients between the bound and free analytes. Through the introduction of the mathematical expression of lability factor, the modified effective average diffusion coefficient was proven to be more suitable for describing the passive sampling kinetics in the presence of mobile binding matrixes. Thereafter, the lability factors of the bound polycyclic aromatic hydrocarbons (PAHs) with sodium dodecylsulphate (SDS) micelles as the binding matrixes were figured out according to the improved theory. The lability factors were observed to decrease with larger binding ratios and smaller micelle sizes, and were successfully used to predict the mass transfer efficiencies of PAHs through DBLs. This study would promote the understanding of the availability of bound analytes for passive sampling based on the theoretical improvements and experimental assessments.

Nanotechnology permits broad advances in agriculture. However, as it is still at a relatively early stage of development, the potential risks remain unclear. Herein, for the first time, we reveal the following: 1) the impact of multi-walled carbon nanotubes (MWCNTs) on the accumulation/depuration behaviors of contaminants in crop, mustard (Brassica juncea) and 2) the permeability and transportability of MWCNTs in intact mature mustard plants. Using an in vivo sampling technique, the kinetic accumulation/depuration processes of several contaminants in mustard plans exposed to MWCNTs were traced and an enhancement of contaminant accumulation in living plants was observed. Meanwhile, we observed that the MWCNTs permeated into the roots of intact living plants (three months old) and were then transported to the upper organs under the force of transpiration steam. This study demonstrated that MWCNTs can act as contaminant carriers and be transported to the edible parts of crops.

In this study, the hollow fiber-liquid phase microextraction (HF-LPME) coupled gas chromatograph/mass spectrometry (GC/MS) was firstly developed to determine 10 organochlorine pesticides (OCPs) in ecological textiles. The present method can offer high separation efficiencies with minimal sample and solvent consumption. The extraction conditions were optimized, including the types of hollow fiber and organic solvent, the extraction time, the stirring and the salinity. Under the optimized conditions, the linear ranges of OCPs in cotton, terylene and fur samples were 5-1000 ng/g, 10-1000 ng/g and 10-800 ng/g, respectively, and the detection limit of the three samples were 0.07-2.30 ng/g, 0.89-1.66 ng/g and 0.06-1.04 ng/g, respectively. The optimized method was then successfully used to determine the OCPs in 3 kinds of spiked real samples, including cotton, terylene and fur. The good recoveries and RSDs of the quantification in real textile samples were obtained and the results were confirmed by the traditional liquid extraction method (GB/T 18412-2006). This study proved that the HF-LPME method, which was simple, low-cost and virtually solvent-free, was reliable for the qualitative and quantitative analysis of the harmful OCP residues in ecological textiles.