Porous chlorine-functionalized covalent organic framework anchored graphene aerogel composite for synergically enhanced solid phase microextraction of polychlorinated naphthalene in environmental water.

The residues of polychlorinated naphthalenes (PCNs) produced in multiple industrial production and life processes are continuously entering environmental waters through atmospheric deposition and land drainage, and the water pollution caused by PCNs is continuing public concern due to their potential threat to aquatic ecosystems and public health. Herein, a new chlorine-functionalized covalent organic framework anchored graphene aerogel (COF-GA) was synthesized by covalent modification technology and used as fiber coating of solid-phase microextraction for synergically enhanced extraction of PCNs in environmental water. The extraction efficiency of COF-GA coated fiber was superior to commercial fiber due to the multiple interactions (π-π, hydrophobic interaction, and halogen bonding interaction). The COF-GA coated fiber has good stability, can avoid water vapor interference at 80 °C for a long time (30 -50 min) to maintain adsorption equilibrium, and can be reused at least 96 times. Combined with gas chromatography-tandem mass spectrometry, a sensitive method for the high-efficient enrichment (enrichment factors were 501 -7453 folds) and ultra-sensitive detection (LODs were 0.001 -0.428 pg/mL) of PCNs in environmental water was established. The enrichment factor for PCNs is significantly higher than in previous studies. This proposed method provides new technical support for the daily monitoring and risk assessment of trace PCNs in environmental water.

A three-dimensional hierarchical porous graphene aerogel as a fiber coating for headspace solid-phase microextraction: Enhancing the enrichment and detection of polychlorinated naphthalenes in fish.

In this study, a novel three-dimensional hierarchical porous deep eutectic solvents-modified graphene aerogel (3D DES-GA) was synthesized for use as a solid-phase microextraction (SPME) fiber coating. The SPME fiber was characterized by its fluffy and hierarchical porous structure, uniform thickness, and rapid mass transfer capabilities. This fiber demonstrated a lifetime (≥160 uses) and excellent precision (with relative standard deviations of 2.4-6.6% for single fiber and 6.0-9.8% for fiber-to-fiber repeatability). The SPME fiber also exhibited remarkable extraction performance for polycyclic aromatic hydrocarbons and polychlorinated biphenyls, which are common persistent organic pollutants in environmental samples. When combined with gas chromatography-tandem mass spectrometry, the method allowed for high-efficiency extraction (enrichment factors ranging from 1225 to 4652 folds) and sensitive determination (limit of detection ranging from 0.010 to 0.056 pg g-1) of polychlorinated naphthalenes (PCNs) in complex samples. To validate this method, we applied it to the determination of four PCNs in five types of fish tissues. The results revealed the presence of 1-chloronaphthalene at concentrations of 7.0 ± 2.9-34.8 ± 2.1 pg g-1 and 1,4-dichloronaphthalene at concentrations of 6.0 ± 0.3-10.9 ± 1.4 pg g-1 in three fish species. Compared with reported sample pretreatment methods reported in the literature, this proposed headspace SPME method offers additional advantages, including simplicity of operation and reduced sample and organic solvent consumption.

Hydrophilic molecularly imprinted resin-hexagonal boron nitride composite as a new adsorbent for selective extraction and determination of a carcinoid tumor biomarker in urine.

BACKGROUND: The detection of disease biomarkers in biological samples plays an important role in early diagnosis and treatment of carcinoid tumor. However, due to the complexity of biological samples and the extremely low concentration of disease biomarkers, sample pretreatment is still the bottleneck of achieving accurate quantitative determination. In this work, new hydrophilic molecularly imprinted resin-hexagonal boron nitride (HMIR-h-BN) composites were developed and used as a new solid phase extraction (SPE) adsorbent for selective detection of 5-hydroxyindoleacetic acid (5-HIAA), a biomarker of carcinoid tumor, in urine. RESULTS: Twenty-two types of HMIR-h-BN were successfully synthesized through growing hydrophilic molecularly imprinted resin on surface of activated two-dimensional h-BN nanosheets, and preparation parameters affecting the adsorption performance of HMIR-h-BN were investigated and optimized through adsorption experiments. HMIR-h-BN #19 (the ratio of resorcinol to hexamethylenetetramine: 6:3; the dosage of h-BN: 300 mg; the dosage of dummy template: 0.12 mmol; the imprinting time: 4 h) has demonstrated to be the optimal material for efficient separation and extraction of 5-HIAA. Combined with HPLC-UV, the limit of detection and the limit of quantification of 5-HIAA in real urine samples were 9.4 ng mL-1 and 31.3 ng mL-1, respectively, the coefficient of determination (R2) was 0.9996 in the linear range of 0.1-300 µg mL-1 and the relative recoveries ranged from 86.9 % to 97.7 % with RSD ≤5.1 %. Moreover, after being processed by HMIR-h-BN-SPE, there are no interferences from other peaks at the peak position of 5-HIAA. SIGNIFICANCE: The HMIR-h-BN composite has been demonstrated to be capable of selective extraction of 5-HIAA from urine samples and have a significant purification effect. Based on the established HMIR-h-BN-SPE-HPLC-UV method, accurate quantitative determination of 5-HIAA in urine samples was achieved, which is expected to be applied in the early diagnostic of carcinoid tumor.

Identification of tyrosinase inhibitors in defatted seeds of evening primrose (Oenothera biennis L.) by affinity-labeled molecular networking.

The defatted seeds of evening primrose (DE), a by-product of evening primrose oil extraction, are currently underutilized. This study aimed to valorize DE by examining its effects on melanogenesis and tyrosinase activity in zebrafish embryos and in vitro, and an innovative affinity-labeled molecular networking workflow was proposed for the rapid identification of tyrosinase inhibitors in DE. Our results indicated DE significantly reduced melanin content (53.3 % at 100 µg/mL) and tyrosinse activity (80.05 % for monophenolase and 70.40 % for diphenolase at 100 µg/mL). Furthermore, through the affinity-labeled molecular networking approach, 20 compounds were identified as potential tyrosinase inhibitors within DE, predominantly flavonoids and tannins characterized by catechin and galloyl substructures. Seven of these compounds were isolated and their inhibitory effects on tyrosinase were validated using functional assays. This study not only underscores the potential of DE as a rich source of natural tyrosinase inhibitors but also establishes the effectiveness of affinity-labeled molecular networking in pinpointing bioactive compounds in complex biological matrices.

Determination of alectinib and its active metabolite in plasma by pipette-tip solid-phase extraction using porous polydopamine graphene oxide adsorbent coupled with high-performance liquid chromatography-ultraviolet detection.

Alectinib is known as an effective targeted drug, which has excellent therapeutic effect on non-small cell lung cancer and can significantly prolong the survival of patients. Therapeutic drug monitoring is necessary due to the photo-instability of alectinib and the individual differences in patients. In this work, a porous polydopamine graphene oxide composite (PDAG) was prepared by a simple surface modification method. A PDAG-based pipette-tip solid-phase extraction (PT-SPE) coupled with HPLC-UV detection was proposed for the separation and detection of alectinib and its active metabolite M4 in plasma. The method was methodologically validated and showed good linearity in the range of 50-5000 ng mL-1 (R2 > 0.9995). The limit of detection (LOD) was 4.8 ng mL-1 and 3.9 ng mL-1 for alectinib and M4, respectively, and the limit of quantitation (LOQ) was 16.1 ng mL-1 and 13.1 ng mL-1, respectively. The intra-day and inter-day precision expressed by coefficient of variation was less than 4.8 %. The recovery of this method ranged from 84.9 % to 103.5 % with a standard deviation of less than 4.3 %. In conclusion, the established method is accurate, stable and inexpensive, and can be used to monitor the levels of alectinib and M4 in plasma, which provide technical and data support for exploring optimal individualized remedial dosing regimens.

Miniaturized centrifugation accelerated pipette-tip matrix solid-phase dispersion based on poly(deep eutectic solvents) surface imprinted graphene oxide composite adsorbent for rapid extraction of anti-adipogenesis markers from Solidago decurrens Lour.

Overweight and obesity are the causes of many diseases and have become global "epidemics". Research on natural active components with anti-adipogenesis effects in plants has aroused the interest of researchers. One of the most critical problems is establishing sample preparation and analytical techniques for quickly and selectively extracting and determining the active anti-adipogenesis components in complex plant matrices for developing new anti-adipogenic drugs. In this study, a new poly(deep eutectic solvents) surface imprinted graphene oxide composite (PDESs-MIP/GO) with high selectivity for phenolic acids was prepared using deep eutectic solvents as monomers and crosslinkers. A miniaturized centrifugation-accelerated pipette-tip matrix solid-phase dispersion method (CPT-MSPD) with PDESs-MIP/GO as adsorbent, coupled with high-performance liquid chromatography, was further developed for the rapid determination of anti-adipogenesis markers in Solidago decurrens Lour. (SDL). The established method was successfully used to determination anti-adipogenesis markers in SDL from different regions, with the advantages of accuracy (recoveries: 94.4 - 115.9 %, RSDs ≤ 9.8 %), speed (CPT-MSPD time: 11 min), selectivity (imprinting factor: ∼2.0), and economy (2 mg of adsorbent and 1 mL of solvents), which is in line with the current advanced principle of "3S+2A" in analytical chemistry.

Development and validation of an online dynamic prognostic nomogram for incidental gallbladder adenocarcinoma patients without distant metastasis after surgery: a population-based study.

Background: Gallbladder cancer is the most common malignant tumor of the biliary system, most of which is adenocarcinoma. Our study explored developing and validating a nomogram to predict overall and cancer-specific survival probabilities internally and externally for incidental gallbladder adenocarcinoma patients without distant metastasis after surgery. Methods: Patients screened and filtered in the Surveillance, Epidemiology, and End Results (SEER) database, whose years of diagnosis between 2010 and 2015 were collected as a derivation cohort, while those between 2016 and 2019 were a temporal validation cohort. Overall survival (OS) and cancer-specific survival (CSS) were chosen as the primary and secondary endpoints of the retrospective study cohort. Potential clinical variables were selected for a Cox regression model analysis by performing both-direction stepwise selection to confirm the final variables. The performance of final nomograms was evaluated by Harrell's C statistic and Brier score, with a graphical receptor operating characteristic (ROC) curve and calibration curve. Results: Seven variables of age, race, tumor size, histologic grade, T stage, regional lymph nodes removed, and positive regional lymph nodes were finally determined for the OS nomogram; sex had also been added to the CSS nomogram. Novel dynamic nomograms were established to predict the prognosis of incidental gallbladder adenocarcinoma patients without distant metastasis after surgery. The ROC curve demonstrated good accuracy in predicting 1-, 3-, and 5-year OS and CSS in both derivation and validation cohorts. Correspondingly, the calibration curve presented perfect reliability between the death or cancer-specific death probability and observed death or cancer-specific death proportion in both derivation and validation cohorts. Conclusion: Our study established novel dynamic nomograms based on seven and eight clinical variables separately to predict OS and CSS of incidental gallbladder adenocarcinoma patients without distant metastasis after surgery, which might assist doctors in advising and guiding therapeutic strategies for postoperative gallbladder adenocarcinoma patients in the future.

Simultaneous determination of three biomarkers of non-small cells lung cancer in urine by pipette-tip solid-phase extraction coupled with liquid chromatography tandem mass spectrometry.

Simultaneous determination of multiple biomarkers can improve the effectiveness and accuracy of cancer diagnosis. Cortisol, cortisone, and 4-methoxyphenylacetic acid (4-Me) are metabolic biomarker group with high specificity and sensitivity for the diagnosis of non-small cells lung cancer (NSCLC), and the development of their simultaneous determination method is desired. Herein, a simple, sensitive, and low-cost method involving pipette-tip solid-phase extraction (PT-SPE) using anion exchange adsorbent (MAX) coupled with liquid chromatography tandem mass spectrometry (LC-MS/MS) was developed for the simultaneous determination of three biomarkers (cortisol, cortisone, and 4-Me) in human urine. The sample (0.1 mL), adsorbent (1.5 mg) and organic reagent (3.5 mL) of MAX-PT-SPE are less consumed, and have the advantages of easy access to raw materials, simple assembly, convenient on-site instant extraction, low pollution, and low cost. The limits of detection of the three biomarkers were 0.006-0.024 ng mL-1, the recoveries of three spiked levels (2, 50, and 500 ng mL-1) were 91.0%-99.3%, with the relative standard deviations (RSDs) ≤ 5.9%. Finally, the MAX-PT-SPE-LC-MS/MS method achieved the quantitative analysis of cortisol, cortisone, and 4-Me in urine of different patients of NSCLC. This method is expected to be used in the non-invasive auxiliary diagnosis of NSCLC, and it provides a new strategy for multi-molecular diagnosis and multi-omics combined diagnosis.

Rapid extraction of osimertinib and its active metabolite in urine by miniaturized centrifugal spin-column extraction using ionic liquid hybrid hierarchical porous adsorbent.

Osimertinib (OSIM) is widely used as a mainstream drug for the treatment of non-small cell lung cancer (NSCLC). However, the lack of a rapid extraction and detection method for OSIM and its metabolite, AZ-5104, has limited clinical drug metabolism and drug resistance research because the drug is unstable. In this study, a new ionic liquid hybrid hierarchical porous material (IL-HHPM) was synthesized with hierarchical porous structures, including micropores (1.6-2.0 nm), mesopores (2.0-50.0 nm), macropores (50.0-148.7 nm), and multiple functional groups via a one-step hydrothermal method using silanized ionic liquids (IL) as functionalized hybrid monomer. The IL-HHPM has the advantages of a high specific surface area (437.4 ± 4.6 m2 g-1), sizable pore volume (0.74 cm3 g-1), and fast mass transfer, additionally, the IL-HHPM adsorbed OSIM and AZ-5104 via π-π interactions and hydrogen bonding. OSIM and AZ-5104 were rapidly extracted and measured in human urine using rapid and miniaturized centrifugal spin-column extraction (MCSCE), which was based on the IL-HHPM. The optimized factors for the extraction recoveries of OSIM and AZ-5104 were adsorbent dosage (8.0 mg), sample volume (0.5 mL), and operation time (9.0 min), and markedly reduced the adsorbent dosage and operation time. The IL-HHPM-MCSCE-HPLC method displayed good linearity (0.02-5.00 µg mL-1, r ≥ 0.9997), satisfying accuracy (spiked recoveries of 87.7%-100.0%), and good precision (RSDs ≤ 7.0%). The developed method is rapid, sensitive, and reproducible for the simultaneous determination of trace level of OSIM and AZ-5104 in human urine.

Preparation of poly (methacrylic acid)/graphene oxide aerogel as solid-phase extraction adsorbent for extraction and determination of dopamine and tyrosine in urine of patients with depression.

Dopamine (DA) and l-tyrosine (l-Tyr) are neurotransmitters involved in various neuropsychiatric disorders. Therefore, it is important to monitor their levels for diagnosis and treatment. In this study, we synthesized poly (methacrylic acid)/graphene oxide aerogels (p(MAA)/GOA) by in situ polymerization and freeze-drying using graphene oxide and methacrylic acid as substrates. Then, the p(MAA)/GOA were applied as solid-phase extraction adsorbents to extract DA and l-Tyr from urine samples, followed by quantification using high performance liquid chromatography (HPLC). The p(MAA)/GOA showed better adsorption performance for DA and l-Tyr than commercial adsorbents, likely as a result of the strong adsorption of the target analytes via π-π and hydrogen bonding interactions. Further, the developed method had good linearity (r > 0.9990) at concentrations of DA and l-Tyr of 0.075-2.0 and 0.75-20.0 µg mL-1, respectively, as well as a limit of detection of 0.018-0.048 µg mL-1, limit of quantitation of 0.059-0.161 µg mL-1, spiked recovery of 91.1-104.0%, and interday precision of 3.58-7.30%.The method was successfully applied to determine DA and l-Tyr in the urine samples of patients suffering from depression, demonstrating its potential for clinical applications.

Honeycomb resin-based spin-column solid-phase extraction for efficient determination of alectinib and its metabolite in human urine.

Alectinib and its metabolite, M4, have demonstrated a satisfactory clinical therapeutic effect in the treatment of anaplastic lymphoma kinase-positive advanced non-small-cell lung cancer. Due to individual differences among patients, therapeutic drug monitoring (TDM) is critical for guaranteeing appropriate clinical drug use. To realize TDM for alectinib and its metabolite, M4, a honeycomb phenol-formaldehyde resin (PFR) with excellent hydrophilic properties, abundant adsorption force, and a stable porous structure was synthesized by modifying the porogens F127 and P123. The prepared PFR was employed as an adsorbent in a simple and efficient spin-column solid-phase extraction (SPE) process. A rapid method for detecting alectinib and its metabolite M4 in urine was thereby established. The established method showed a linear range of 0.0200 µg mL-1-5.00 µg mL-1 and the recovery range of 98.8-103% for spiked urine samples, with relative standard deviations of ≤ 4.87% (n = 3). Our results proved the practicability of the proposed honeycomb-PFR spin-column SPE method in TDM for alectinib and its metabolite, M4.

Miniaturized extraction and determination of swelling agents in fruits and vegetables based on deep eutectic solvent-molecularly imprinted hydrophilic resin.

The overuse of swelling agents in fruits and vegetables has rapidly increased, resulting in food safety problems. Hence, a new method for the selective extraction and detection of thidiazuron (TDZ) and forchlorfenuron (KT30) was developed using deep eutectic solvent-molecularly imprinted hydrophilic resin (DES-MIHR) as a pipette tip solid-phase extraction (PT-SPE) adsorbent with excellent molecular recognition in aqueous matrixes. DES-MIHR interacted with TDZ and KT30 via π-π interactions and hydrogen bonding. The miniaturized PT-SPE can be performed with just 5.0 mg adsorbent, 0.3 mL water, and 0.2 mL eluent, thus having the advantage of the low consumption of adsorbent and organic reagents. The performance of the DES-MIHR-PT-SPE-high-performance liquid chromatography (HPLC) method was demonstrated with the recoveries from various fruits and vegetables being 81.1-102.9 % (RSD ≤ 7.1 %). Thereby indicating the general applicability of the developed method for the accurate determination of trace swelling agents in fruits and vegetables.

Novel molecularly imprinted phenolic resin-dispersive filter extraction for rapid determination of perfluorooctanoic acid and perfluorooctane sulfonate in milk.

Perfluorooctanoic acid (PFOA) and perfluorooctane sulfonate (PFOS) are emerging pollutants that threaten food safety. Herein, a rapid, accurate, and selective method for determination of PFOA and PFOS in milk was established by using new molecularly imprinted phenolic resin (MIP-PR) as the adsorbent of dispersive filter extraction (DFE) combined with liquid chromatography-tandem mass spectrometry (LC-MS/MS). MIP-PR was synthesized at room-temperature using m-aminophenol, glutaraldehyde, and perfluorononanoic acid as the monomers, cross-linkers, and virtual templates, respectively, and exhibited rapid mass transfer (30 s), high selectivity (imprinted factors > 3.7), and large adsorption capacity (>54.6 mg/g). Compared with reported methods, the developed MIP-PR-DFE method is fast, selective, inexpensive, and shows good purification and enrichment efficiency. The proposed MIP-PR-DFE-LC-MS/MS exhibited low limits of detection (0.006-0.022 ng/mL), high recoveries (94.7-109 %), and good precision (RSDs ≤ 9.5 %). This study provides a new idea for the development of imprinted resin adsorbents for perfluorinated compound, and a new method for sample pretreatment for monitoring of PFOA and PFOS in food.

Selective enrichment and determination of polychlorinated biphenyls in milk by solid-phase microextraction using molecularly imprinted phenolic resin fiber coating.

Owing to the severe toxicity and health hazard of polychlorinated biphenyls (PCBs) to humans, the efficient separation and determination of PCBs in dairy products is highly desirable and challenging. In this study, a new solid-phase microextraction (SPME) fiber was prepared by coating of a new molecularly imprinted phenolic resin (MIPR) in situ using a covalent grafting method. The MIPR coating, synthesized from 4-mercaptophenol and glutaraldehyde, provides rough surface with more adsorption sites; furthermore, the coating has a thickness of 1.0 µm, resulting in rapid equilibration. This new device has the advantages such as less coating peeling from the substrate and selective recognition enhancement of the coating. A highly selective and sensitive SPME-based method was developed using the developed fiber, coupled with GC-MS/MS, for the determination of polychlorinated biphenyls (PCBs) in milk samples. The developed MIPR-HS-SPME-GC-MS/MS method showed low detection limits (0.012-0.066 pg mL-1), good linearity (r ≥ 0.9991), satisfactory recovery (77.5-116.7%), efficient enhancement factors (362-2034 folds) and good reusability (50 cycles). Therefore, this is a simple and efficient strategy for monitoring trace PCBs in complex samples and is a potential alternative for improving the selectivity of SPME fibers by introducing MIPR into the fiber coating.

Surgical Management of Cholecystoenteric Fistula in Patients With and Without Gallstone Ileus: An Experience of 29 Cases.

Background: Cholecystoenteric fistula (CEF) is an uncommon complication of cholelithiasis. Here, we report our experience on diagnostic methods and surgical management of CEF patients with and without gallstone ileus (GI). Methods: This is a retrospective cases series over an 11-year period (2011-2022). Data analyzed included preoperative characteristics, ultrasound, imaging features, operation findings and postoperative course. Results: A total of 29 patients diagnosed with CEF were enrolled, 51.7% (15/29) of whom were female, with a median age of 66 years (range: 35-96 years). With regards to subtype distribution, seventeen patients had cholecystoduodenal fistula (CDF), six had cholecystoconlonic fistula (CCF), three exhibited cholecystogastric fistula (CGF), one CDF combination with CCF and two CDF combination with type I Mirizzi syndrome. Twelve patients presented with gallstone ileus, and received one stage procedure or simple Enterolithotomy. The median operation time and blood loss of 157 min (range: 65-360 min) and 40 ml (range: 10-450 ml), respectively. Surgical complications, evidenced by fistula recurrence, were recorded in three patients (3/22; 13.6%), while four (4/29; 13.8%) and one patient (1/29; 3.4%) presented with wound infection and residual stone in common bile duct, respectively. No deaths were reported in our study. Conclusion: CEF is a rare complication of gallstone disease that is occasionally found during operation. To date, no consensus has been reached regarding efficacious treatment therapies for CEF patients. For a CEF patient with GI, one stage procedure should be selected prudently, while simple Enterolithotomy would be a mainstream choice for relieving bowel obstruction.

Rapid and inexpensive nylon-66-filter solid-phase extraction followed by gas chromatography tandem mass spectrometry for analyzing perfluorinated carboxylic acids in milk.

In this study, a new rapid and inexpensive filter solid-phase extraction method (FSPE) was developed for the extraction and separation of five perfluorinated carboxylic acids (PFCAs) (namely, perfluorooctanoic acid, perfluorononanoic acid, perfluorodecanoic acid, perfluoroundecanoic acid, and perfluorododecanic acid) from milk samples. Commercial nylon 66 syringe filters were used as adsorbents without additional modification. The proposed method could achieve the fast adsorption of analytes by benefitting from the advantages of using the nylon 66 filter membrane on PFCAs with multiple adsorption interactions, namely, hydrophobic interactions and hydrogen bonds. The FSPE was designed to achieve the rapid isolation of analytes based on the rapid solid-liquid separation while using the solid-phase extraction disk. PFCAs residues in milk were extracted by first flowing the samples through a nylon 66 syringe filter from top to bottom. Double contact desorption with methanol was then accomplished by pulling and pushing the syringe, followed by derivatization with acetyl chloride-methanol. Finally, the extracted PFCAs residues were monitored using gas chromatography-tandem mass spectrometry (GC-MS/MS) quantification. Under optimal conditions, the established method presented good linearity (correlation coefficient ≥ 0.9996), precision (relative standard deviation ≤ 13%), accuracy (81-105%), sensitivity (limits of quantification: 4-18 ng kg-1) and extraction performance (10 min).

Analysis of anticancer compound, indole-3-carbinol, in broccoli using a new ultrasound-assisted dispersive-filter extraction method based on poly(deep eutectic solvent)-graphene oxide nanocomposite.

Indole-3-carbinol (I3C), an important anticancer compound found in broccoli, has attracted considerable attention. The rapid extraction and accurate analysis of I3C in the pharmaceutical industry in broccoli is challenging as I3C is unstable at low pH and high temperature. In this study, a rapid, accurate, and low-cost ultrasound-assisted dispersive-filter extraction (UADFE) technique based on poly(deep eutectic solvent)-graphene oxide (PDES-GO) adsorbent was developed for the isolation and analysis of I3C in broccoli for the first time. PDES-GO with multiple adsorption interactions and a fast mass transfer rate was synthesized to accelerate adsorption and desorption. UADFE was developed by combining dispersive solid-phase extraction (DSPE) and filter solid-phase extraction (FSPE) to realize rapid extraction and separation. Based on the above two strategies, the proposed PDES-GO-UADFE method coupled with high-performance liquid chromatography (HPLC) allowed the rapid (15-16 min), accurate (84.3%-96.4%), and low-cost (adsorbent: 3.00 mg) analysis of I3C in broccoli and was superior to solid-phase extraction, DSPE, and FSPE methods. The proposed method showed remarkable linearity (r=0.9998; range: 0.0840-48.0 µg/g), low limit of quantification (0.0840 µg/g), and high precision (relative standard deviation ≤5.6%). Therefore, the PDES-GO-UADFE-HPLC method shows significant potential in the field of pharmaceutical analysis for the separation and analysis of anti-cancer compounds in complex plant samples.

Headspace solid-phase-microextraction using a graphene aerogel for gas chromatography-tandem mass spectrometry quantification of polychlorinated naphthalenes in shrimp.

Polychlorinated naphthalenes (PCNs) are emerging organic pollutants that are harmful to the environment and human health. In this study, a headspace solid-phase-microextraction (HS-SPME)-gas chromatography-tandem mass spectrometry method for the separation and enrichment of PCNs in shrimp was developed and validated. A graphene aerogel was prepared by modifying graphene oxide with a deep eutectic solvent to prevent graphene oxide stacking. As a result, the aerogel had a three-dimensional porous structure, which resulted in easy sorption/desorption for PCNs, and was used as the SPME fiber coating. Next, the experimental parameters for the saponification of the sample matrix and the extraction and desorption of the PCNs were systematically optimized. After optimization, the method showed good linearity (R2≥0.9968), low limits of detection (0.00983-0.0661 pg g-1), and satisfactory recoveries (80.4-108%). Crucially, compared with previously reported methods, this method does not require the use of large amounts of organic reagents or complex operations, giving it the advantages of simplicity, sensitivity, and environmental friendliness. As an example of the practical application of the developed method, the PCNs in river and sea shrimp were quantified.

An integrated solid phase extraction with ionic liquid-thiol-graphene oxide as adsorbent for rapid isolation of fipronil residual in chicken eggs.

A rapid and economic integrated solid-phase extraction (ISPE) method with ionic liquid-thiol-graphene oxide composite (IL-TGO) as a new adsorbent was established for the extraction of fipronil in chicken eggs. In this study, ISPE, a new form of solid-phase extraction, which combined the advantages of pipette-tip solid phase extraction (PT-SPE) and dispersive solid-phase extraction (DSPE), achieving rapid extraction of analyte with only a small amount of adsorbent. The three-dimensional porous IL-TGO was a new ideal adsorbent for fipronil due to the multiple adsorption interactions (π-π interaction, hydrophobic interaction and hydrogen bond), large adsorption capacity and fast adsorption rate. For this ISPE procedure, the analyte was adsorbed by IL-TGO through the pipette tip mode and then eluted through dispersive mode. Under the optimized condition, the proposed method performed following merits: good linearity (r = 0.9999), precision (RSD ≤ 6.3%), high recoveries (83.7% to 97.7%), rapid extraction (16 min), low consumption of adsorbent (3.00 mg of IL-TGO). The excellent recyclability of the ISPE device and the reusability of IL-TGO were observed and high recovery of fipronil (> 90%) was obtained after fifteen cycles. This work might provide promising strategy for the sensitive extraction and analysis of trace levels of fipronil from egg products.

Improved Solid-Phase Extraction for Simple, Sensitive, and Efficient Determination of Trace Plant Growth Regulators in Cherry Tomatoes by High-Performance Liquid Chromatography.

The overuse of plant growth regulators (PGRs) in agricultural products has gradually increased in recent years, resulting in hazardous effects on food safety and human health. For the first time, a sensitive, accurate, and low-cost analytical method involving improved solid-phase extraction coupled with high-performance liquid chromatography was developed to determine trace PGRs in cherry tomatoes. Thereafter, the extraction mechanism and conditions were elucidated. Under optimized conditions, good linearity (0.04-400 ng g-1; r ≥ 0.9996) and lower limits of detection (0.005-0.006 ng g-1) were observed. The recoveries were 81.4-90.1%, with relative standard deviations of ≤6.7% (three levels). Finally, the developed method was successfully used to detect trace PGRs in cherry tomatoes. The results illustrated that this sensitive method shows great potential for application to monitor trace PGRs in agricultural products and, thus, provide technical support for food safety and public health.