NOVA1 prevents overactivation of the unfolded protein response and facilitates chromatin access during human white adipogenesis.

The molecular mechanism underlying white adipogenesis in humans has not been fully elucidated beyond the transcriptional level. Here, we found that the RNA-binding protein NOVA1 is required for the adipogenic differentiation of human mesenchymal stem cells. By thoroughly exploring the interactions between NOVA1 and its binding RNA, we proved that NOVA1 deficiency resulted in the aberrant splicing of DNAJC10 with an in-frame premature stop codon, reduced DNAJC10 expression at the protein level and hyperactivation of the unfolded protein response (UPR). Moreover, NOVA1 knockdown abrogated the down-regulation of NCOR2 during adipogenesis and up-regulated the 47b+ splicing isoform, which led to decreased chromatin accessibility at the loci of lipid metabolism genes. Interestingly, these effects on human adipogenesis could not be recapitulated in mice. Further analysis of multispecies genomes and transcriptomes indicated that NOVA1-targeted RNA splicing is evolutionarily regulated. Our findings provide evidence for human-specific roles of NOVA1 in coordinating splicing and cell organelle functions during white adipogenesis.

Cell Models for Birth Defects Caused by Chloroethyl Nitrosourea-Induced DNA Lesions.

ABSTRACT: Birth defects have been linked to administration of alkylating agents during pregnancy. The anti-tumor efficacy of alkylating agents correlate with their ability to induce DNA lesions, especially interstrand crosslinks (ICLs). Yet the role of DNA damages in birth defects remains to be clarified, owing, in part, to a lack of cell models. Here we generate DNA lesions in NIH/3T3 cells to mimic defects in fetus triggered by 3-Bis(2-chloroethyl)-1-nitrosourea (BCNU, carmustine). CCK-8 assay suggests that BCNU-induced cell death was dose-dependent. Alkaline comet tests and γ-H2AX staining confirm DNA ICLs and other forms of DNA damages caused by BCNUs. The cell cycle analysis shows cells arrest in G2/M phase until crosslinks repair is complete. Taken together, all these experiments demonstrate we have successfully established normal cell models for birth defects caused by BCNU-mediated DNA damages. The model can not only guide the development of effective and low-toxicity anticancer drugs, but also be of great significance for the study of neonatal malformation triggered by BCNUs.

The Application of Temporal-Fasciae-Complex Sheet in Treating Severe Blepharoptosis.

AIM: To introduce the application of the temporal-fasciae-complex sheet in treating severe blepharoptosis by frontalis suspension and evaluate its postoperative effect. METHODS: Between 2008 and 2016, 25 patients (33 eyelids) underwent this procedure. A 3-cm incision in the temporal region was made to harvest a sheet of deep temporal fascia with the loose aponeurosis attached on both sides. The sheet was then grafted through a preseptal tunnel to perform the suspension. The margin reflex distance 1 after suspension (MRD1S), the margin reflex distance 1 as lifting eyebrow forcefully (MRD1F), the eyelid excursion and the closable eyelid function were used to evaluate the postoperative effect. RESULTS: A total of 22 patients (30 eyelids) completed the study with a mean follow-up period of 23 ± 8.78 months. There was a statistically significant difference between the MRD1 and MRD1S (p < 0.05), the preoperative and postoperative MRD1F (p < 0.05), the preoperative and postoperative eyelid excursion (p < 0.05). All the upper palpebral margins were located above the pupils and no longer affected visual acuity in primary gaze. No severe complication and recurrence were documented within a maximum follow-up period of 36 months. CONCLUSIONS: Frontalis suspension with the temporal-fasciae-complex sheet is an efficient method to correct severe blepharoptosis with less complications and recurrences. The application of the sheet can not only overcome the influence of adhesion but also lift the eyelid both functionally and cosmetically. LEVEL OF EVIDENCE IV: This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266 .

A nanofiber mat prepared from sulfonated polyaniline for solid-phase extraction of fluoroquinolones from water and biological fluids prior to their quantitation by UPLC-MS/MS.

A bifunctional sulfonated polyaniline nanofiber mat (NFM) was synthesized by oxidative polymerization and by using polyacrylonitrile nanofiber mat (NFM) as the template. The adsorption capacity of the NFM for fluoroquinolones (FQs) is distinctly improved and the adsorption was a spontaneous process. According to theoretical calculations, hydrogen bonding and ion-exchange interaction are the two major kinds of interaction mechanisms between adsorbent and FQs. The adsorption and desorption properties for FQs were systematically evaluated by adsorption isotherms and by thermodynamic and kinetic studies. The results indicate that the NFM is a viable sorbent for FQs because of rapid mass transfer and good adsorption/desorption efficiency. The NFM is re-usable for at least 20 cycles without decline in performance. Following desorption of the FQs with 10% (V/V) formic acid/acetonitrile, they were quantified by UPLC with MS/MS detection. The sorbent was applied to the solid phase extraction of the FQs norfloxacin, ciprofloxacin, ofloxacin, enrofloxacin, danofloxacin, pefloxacin, marbofloxacin, lomefloxacin and difloxacin from water and biological fluids. Figures of merit include (a) low limits of detection (0.5-1.5 ng L-1 for water, 0.016-0.052 µg L-1 for urine and serum), (b) high recoveries from spiked samples (82.3%-109.4%) with low relative standard deviations (1.1%-12.3%); (c) short extraction times (2 min), and (d) low adsorbent dosage (4 mg). Graphical abstractSchematic representation of a bi-functional sulfonated polyaniline nanofiber mat (NFM) for solid phase extraction (SPE) of fluoroquinolones (FQs) in water, urine and serum.

Hypoxic postconditioning attenuates apoptosis via activation of adenosine A2a receptors on dermal microvascular endothelial cells of human flaps.

BACKGROUND: In recent years, many studies have demonstrated that endogenous adenosine induced by ischemia postconditioning reduces apoptosis in various models, but no study has clearly elucidated the effects of hypoxic postconditioning (HPC) in human dermal microvascular endothelial cells (HDMECs) of flaps, and the subtype of adenosine receptors involved remains unknown. In our study, we sought to identify the role of adenosine A2a receptor in the antiapoptotic effects of HPC. MATERIALS AND METHODS: The HDMECs were isolated from human upper eyelid tissue. After hypoxia for 6 h, the HDMECs were either abruptly reperfused with medium for 12 h (reoxygenation) or postconditioned by three cycles of 5 min of transitory reoxygenation and 5 min of rehypoxia followed by 11.5 h of reoxygenation. CGS-21680 was used as an adenosine A2a agonist. RESULTS: Adenosine A2a receptors were found in the cytoplasm of HDMECs. Hypoxia/reoxygenation (H/R) resulted in severe injury in HDMECs as evidenced by an increase in apoptosis percentage and an increase in expressions of apoptosis-related proteins (the ratio of Bax/Bcl-2 and caspase-3), which can be significantly attenuated by HPC treatment or exposure to CGS-21680, a selective adenosine A2a receptor agonist (all P values < 0.05). Meanwhile, HPC treatment or CGS-21680 significantly activated A2a receptors compared with the hypoxia/reoxygenation group (P < 0.05 versus P < 0.05, respectively). Statistical analysis showed that the increase of cell apoptosis closely correlated inversely with the increase of relative protein level of adenosine A2a receptors (r2 = 0.8177, P < 0.0001). CONCLUSIONS: HPC protects against apoptosis induced by reoxygenation via activation of adenosine A2a receptors on HDMECs.

Hydrophilic Molecularly Imprinted Resorcinol-Formaldehyde-Melamine Resin Prepared in Water with Excellent Molecular Recognition in Aqueous Matrices.

Hydrophilic molecularly imprinted resorcinol-formaldehyde-melamine resin (MIRFM) is synthesized in water and shows excellent molecular recognition in aqueous matrices. The double functional monomers resorcinol and melamine, and the cross-linker formaldehyde, are all hydrophilic, and then the hydrophilic groups (such as hydroxyls, imino groups, and ether linkages) can be introduced into MIRFM, which make the material compatible with aqueous samples. The general principle is demonstrated by the synthesis of MIRFM using sulfanilamide as a dummy template for the selective recognition to sulfonamides (SAs) in milk samples. Resorcinol and melamine can interact with the template mainly by hydrogen bonding and π-π interaction, which makes MIRFM and the analytes have strong affinity. Besides, melamine can improve the rigidity of MIRFM and accelerate the polymerization process, so there is no need to add base or acid as a catalyst, which guarantees the success of molecular imprinting. MIRFM shows higher recovery and improved purification effect for SAs, in comparison to silica, HLB, C18, and SCX. Because of its excellent hydrophilicity and specificity, MIRFM is promising to be applied in biological, environmental, and clinical fields.

Green synthesis of superhydrophilic resin/graphene oxide for efficient analysis of multiple pesticide residues in fruits and vegetables.

The escalating use of pesticides on fruits and vegetables has raised concerns about potential health risks. Therefore, we developed a superhydrophilic resin/graphene oxide (SR/GO) with rich adsorption interactions using an eco-friendly synthetic approach. SR/GO demonstrated excellent hydrophilicity, ensuring optimal contact with aqueous sample matrices. The multiple adsorption interactions, including π-π conjugation, hydrogen bonding, and electrostatic adsorption, facilitated multi-pesticide residue co-extraction. The synthesized SR/GO was applied to a miniaturized centrifugation-accelerated pipette-tip extraction method, coupled with high-performance liquid chromatography. The optimized method exhibited low consumption (15.0 mg adsorbent), and high efficiency, with low detection limits (1.4-2.9 ng g-1) and high recoveries (75.3-113.0%). Water-compatible SR/GO, along with a miniaturized extraction process, showcases a potent analytical approach for pesticide residue analysis in fruits and vegetables. The significance of this method lies in its ability to ensure agricultural and food safety by using a low-cost and efficient multi-pesticide residue analytical strategy.

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.

Development of a three-dimensional porous ionic liquid-chitosan-graphene oxide aerogel for efficient extraction and detection of polyhalogenated carbazoles in sediment samples.

The three-dimensional porous ionic liquid-chitosan-graphene oxide aerogel (IL-CS-GOA) monolithic adsorbent with a through-hole structure was prepared using natural chitosan (CS) as the skeletal framework, graphene oxide (GO) as the support to provide mechanical strength, and ionic liquid (IL) as the porogen and modifier. The resulting IL-CS-GOA demonstrated a fluffy and porous structure with various pore sizes and excellent regeneration capability (over six cycles). Its specific surface area exceeded that of CS-GOA and IL-GOA by more than 7 times, enhancing its polyhalogenated carbazoles (PHCZs) adsorption capacity. Within 5 min, IL-CS-GOA (1.0 mg) exhibited adsorption amounts of 539 ng mg-1 for 3-bromocarbazole (3-BCZ), 716 ng mg-1 for 2,7-dibromocarbazole (2,7-BCZ), and 798 ng mg-1 for 1,3,6,8-tetrabromocarbazole (1,3,6,8-BCZ), showcasing its rapid mass transfer and high adsorption capabilities. IL-CS-GOA was utilized as the adsorbent for glass dropper extraction (GDE) in conjunction with gas chromatography-mass spectrometry (GC-MS/MS), to develop a highly efficient and accurate method for determining PHCZs in sediments. Under optimal conditions, the established method exhibited a wide linear range (0.4-250 ng g-1, r ≥ 0.9990), low detection limits (0.04-0.24 ng g-1), and satisfactory recoveries (80.5 %-93.8 %), enabling the accurate and rapid detection of PHCZs in sediment samples. This study presents a novel approach for creating three-dimensional porous aerogels, introduces a new form of sample pretreatment using GDE with a monolithic adsorbent, and offers a new method for the determination of PHCZs in environmental matrices.

Dual-template hydrophilic imprinted resin as an adsorbent for highly selective simultaneous extraction and determination of multiple trace plant growth regulators in red wine samples.

In recent years, numerous plant growth regulators have been found in foods and have a toxicity to human health, so its simultaneous multiple monitoring is urgently. For the first time, a rapid, accurate, and high-selective method was established to extract and determine multiple plant growth regulators simultaneously in red wines using a new dual-template hydrophilic molecularly imprinted resin (DHMIR) as an adsorbent of pipette tip solid-phase extraction coupled with HPLC. The as-prepared DHMIR combined the advantages of the hydrophilicity of hydrophilic resin and multi-imprinted recognition of dual-template molecular imprinting, overcoming the poor imprinted recognition ability of traditional imprinting materials in water and low extraction efficiency to multiple targets. Under the optimized conditions, the proposed method exhibited high sensitivity (2.29-3.94 ng mL-1) and recoveries (80.9-109.0 %) using only 15 mg DHMIR. This study provides an effective strategy for rapid, accurate, low-cost, and high-selective determination of the multiple analytes in food samples.

Electrospun chitosan/polyethylene oxide nanofibers mat loaded with copper (II) as a new sensor for colorimetric detection of tetracycline.

Using electrospun chitosan/polyethylene oxide nanofibers mat (CS/PEO NFM) as carrier, Cu@CS/PEO NFM, a new tetracycline (TC) solid-state colorimetric sensor, were simply prepared by directly immobilizing Cu2+ on surface of CS/PEO NFM. After immersing in TC solutions, Cu@CS/PEO NFM can display visible color changes to the naked eye within 5.0 min, and the TC concentration-dependent color changes can also be quantitatively analyzed with a smartphone. Because Cu2+ can enhance the adsorption of CS/PEO NFM for TC, Cu@CS/PEO NFM possess a more sensitive response ability to TC, ensuring that the colorimetric sensing detection will not be interfered by other coexisting drugs. Due to the reversible combination of chitosan and Cu2+, the colorimetric sensing ability of Cu@CS/PEO NFM can be regenerated even after being reused at least 4 times. In addition, the naked eye detection limit of Cu@CS/PEO NFM-based colorimetric sensing is 65 µg kg-1, which does not exceed the maximum residue limit in milk samples set by China (100 µg kg-1). The obtained results fully indicated the practical application value of this method in preventing the hazard of TC residues.

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.

Unique hypoxia-tolerant subpopulations of adipose-derived stem cells: ITGB3+ cells.

BACKGROUND: We found by accident that stem cells could still be isolated from adipose tissue stored for 14 days in sealed tubes, which was distinct from previous protocols. The morphology of these hypoxia-tolerant stem cells also differs from that of conventional adipose-derived stem cells (ADSCs). In this study, we aim to define the newly found subsets. MATERIALS AND METHODS: Stem cells were isolated from adipose tissue that was aspirated immediately or stored for 14 days. The stem cells were then harvested for flowcytometric analysis and differentiation potentials. The expression of hypoxia-inducible factor 1 alpha (HIF-1α) was assayed to confirm the hypoxia-tolerant ability. RNA sequencing (RNA-seq) was performed to find the common signatures of the hypoxia-tolerant cells. The result of bioinformatics was tested by quantitative real-time reverse transcription-polymerase chain reaction (qPCR) and western blotting. RESULTS: Certain subsets of ADSCs can be isolated from adipose tissue stored for 14 days. These survived cells were positive for CD90, CD105, and CD73 and showed multilineage differentiation potentials. The hypoxic condition was evidenced by up-regulation of HIF-1α for 2.0-fold changes (p < 0.05). The hypoxia-tolerant stem cells were distinct from multilineage-differentiating stress-enduring (Muse) cells, previously found stress-enduring stromal cells. RNA-seq suggested that integrin beta 3 (ITGB3) was highly expressed in hypoxia-tolerant subpopulations. The result was further confirmed at transcription and translation levels by qPCR and western blotting (mRNA: 2.9 ± 0.4, p < 0.05; protein: 1.5 ± 0.2, p < 0.05; respectively). The conventional ADSCs are positive for ITGB3, which implies that ITGB3+ cells are subpopulations of heterogeneous ADSCs. CONCLUSIONS: Our study reveals the ITGB3+ subsets with potent hypoxia tolerance, which has significant implications for improving fat retention rates and curing obesity-related diseases.

New insight of immuno-engineering in osteoimmunomodulation for bone regeneration.

With the continuous development of bone tissue engineering, the importance of immune response in bone tissue regeneration is gradually recognized. The new bone tissue engineering products should possess immunoregulatory functions, harmonizing the interactions between the bone's immune defense and regeneration systems, and promoting tissue regeneration. This article will interpret the relationship between the bone immune system, bone tissue regeneration, as well as the immunoregulatory function of bone biomaterials and seed stem cells in bone tissue engineering. This review locates arears for foucusing efforts at providing novel designs ideas about the development of immune-mediation targeted bone tissue engineering products and the evaluation strategy for the osteoimmunomodulation property of bone biomaterials.

Sodium 4-styrenesulfonate functionalized nanofibers mat as 96-well plate solid-phase extraction adsorbent for quantitative determination of multiple ß-agonists residues in pork samples.

In this work, sodium 4-styrenesulfonate functionalized polyacrylonitrile nanofibers mat (SS/PAN NFM) was firstly prepared and applied as 96-well plate solid-phase extraction adsorbent for quantitative determination of seven ß-agonists residues in pork samples. The functional modification endowed the SS/PAN NFM with superior adsorption performance for target ß-agonists. The adsorption process is spontaneous (ΔG < 0), the initial adsorption rate can reach 6.03-9.09 mg/g/min and the maximum adsorption capacity is calculated to be 48.3 mg/g at 298 K. Moreover, SS/PAN NFM can be reused for 12 times without degradation in adsorption capability. Combined with UPLC-MS/MS, the limits of detection can reach 0.006-0.24 µg/kg, the recoveries ranged from 87.2% to 111% and the relative standard deviations of intra-day and inter-day precisions were in the scope of 1.75%-11.6% and 5.08%-13.5%, respectively. The obtained results fully demonstrated the practicability of this method in preventing the hazard of ß-agonists residues.

Regenerative potential of pluripotent nontumorgenetic stem cells: Multilineage differentiating stress enduring cells (Muse cells).

Multilineage differentiating stress enduring cells (Muse cells), double positive for SSEA-3 and CD105, can be isolated by fluorescence-activated cell sorting (FACS) or sever cellular conditions from dermal fibroblasts, bone marrow stem cells (BMSCs), adipose tissue derived stem cells (ADSCs), fresh bone marrow and liposuction fat. When cultured in a single-cell suspension, Muse cells can grow into characteristic cell clusters. Muse cells maintain pluripotency as evidenced by pluripotent markers in vitro. Besides, Muse cells have no tumorigenesis up to 6 months in SCID mice. Muse cells differentiate into cells representative of all three germ layers both spontaneously and under specific induction. In comparison to mesenchymal stem cells (MSCs), Muse cells show higher homing and migration capabilities to damaged sites which is predominantly attributed to S1P-S1PR2 axis. The regenerative effects of Muse cells have been demonstrated by many models in vivo or in vitro, including stroke, intracerebral hemorrhage, myocardial infarction, aortic aneurysm, lung injuries, liver fibrosis, focal segmental glomerulosclerosis, osteochondral defects and skin ulcer. In general, migration, differentiation and paracrine play a pivotal role in the regeneration capability. Here we review the isolation, core properties, preclinical studies as well as the underling molecular and cellular details to highlight their regenerative potential.

Rapid, simple and green solid phase extraction based on polyaniline nanofibers-mat for detecting non-steroidal anti-inflammatory drug residues in animal-origin food.

In this study, polyaniline modified polyacrylonitrile nanofibers mat (PANI NFsM) was prepared as a novel adsorbent for the solid-phase extraction (SPE) of non-steroidal anti-inflammatory drug residues in meat or egg samples. The solvent extracts of samples were simply diluted with water to perform the SPE, and then the eluent was directly analyzed. Significant reduction of the matrix effect was obtained after SPE using only 5 mg of PANI NFsM. The entire sample preparation time is 5-10 times lower than the existing methods. The limits of detection of the target analytes ranging from 0.6 to 12.2 µg kg-1 had already met the demand of food safety monitoring by only 1 g sample. The recoveries ranged from 85.18% to 107.31%, with the intra-day and inter-day relative standard deviations of 2.74% to 16.01%, revealing satisfactory accuracy and precision. Finally, real samples analyses were applied to verify the practicability of the method.

Simultaneous extraction of four plant growth regulators residues in vegetable samples using solid phase extraction based on thiol-functionalized nanofibers mat.

A simple and environmentally friendly sample pretreatment method was established for extraction of four plant growth regulators (PGRs) residues in vegetable samples. In order to effectively extract targets from complex sample matrices, three types of polar groups (COOH, NH2, or SH) functionalized polyacrylonitrile nanofibers mats (PAN NFsM) were prepared and evaluated, respectively. The superior -SH functionalized PAN NFsM was further selected as a novel adsorbent of solid phase extraction (SPE). Under optimal conditions, the proposed method could achieve high sensitivity (0.2-2 ng g-1) and acceptable recovery (88.94%-106.42%) by consuming lower amount of adsorbent (only 5 mg) and organic reagent (only 1.4 mL), and performing much fewer steps than current methods. In addition, the prepared SH-PAN NFsM possessed excellent reusability which could be reused for 6 times without degradation in adsorption capability. These results presented the great potential of the established method for environmental-friendly and efficiently detecting PGRs residues.

Nanofibers mat as sampling module of direct analysis in real time mass spectrometry for sensitive and high-throughput screening of illegally adulterated sulfonylureas in antidiabetic health-care teas.

In this work, novel ionic liquid (IL) functionalized polyacrylonitrile nanofibers mat (IL/PAN-NFsM) was firstly prepared through thiol-ene "click" reaction and evaluated for the establishment of a sensitive and high-throughput screening method. Because of its excellent pre-separation efficiency, IL/PAN-NFsM can adsorb trace-level targets from complex sample matrix within tens of seconds by performing a solid-phase extraction (SPE) process, and then served as sampling modules of direct analysis real time mass spectrometry (DART-MS) without any additional processing. This means the target analytes concentrated on IL/PAN-NFsM were directly desorbed, ionized, and detected by DART-MS. To verify the feasibility of the proposed method, three illegal added synthetic drugs (gliclazide, glimepiride, and gliquidone) were screened in six types of antidiabetic health-care tea samples. The results indicated that the sensitivity is in the level of ng g-1, while total analysis time does not exceed 1.0 min per sample. Moreover, the stability expressed as relative standard deviation (RSD) varies from 1.7% to 17.3%. We proposed a new screening mode based on the direct combination of functionalized NFsM and DART-MS, which is expected to become a universal method in food safety analysis.

Attapulgite/hydrophilic molecularly imprinted monolithic resin composite for the selective recognition and sensitive determination of plant growth regulators in cucumbers.

In this study, through in-situ polymerization process, a novel composite of attapulgite/hydrophilic molecularly imprinted monolithic resin (AT/HMIMR) were prepared in pipette tips for extraction trace plant growth regulators in cucumbers. In the preparation procedure, fibrillar attapulgite nanoparticles were embedded to increase extraction capacity, polyethyleneglycol-6000 was employed as a dual-function porogen, that acted as both the structure-directing agent of the HMIMR and the attapulgite dispersant. N-(1-naphthyl) ethylenediamine dihydrochloride was used as a dummy template to accurate quantification on extraction procedures. Experimental parameters of AT/HMIMR for extracting plant growth regulators from cucumbers were optimized, and the results showed that the recoveries of ranged from 92.4% to 101.1% with relative standard deviations ≤ 6.5% (n = 3). Considering its microporous monolithic column structure, multiple adsorption mechanism, and specific selectivity, AT/HMIMR shows promise for applications that require specific recognition for the analytes in real complex samples.