Magnetic mesoporous polyimide composite for efficient extraction of Rhodamine B in food samples.

A core-shell structured magnetic polyimide composite has been synthesized by the covalent coating of a mesoporous polyimide polymer onto the surface of magnetite nanoparticles. The nanocomposite was characterized by scanning electron microscopy, transmission electron microscopy, N2 adsorption-desorption isotherms, X-ray diffraction, infrared spectroscopy, and vibrating sample magnetometry. The results showed that the prepared composite had a large surface area (306.45 m²/g), a unique pore size (2.15 nm), and strong magnetic properties (45.7 emµ/g), rendering it a promising sorbent material for magnetic solid-phase extraction. The parameters that affect the extraction efficiency of rhodamine B were optimized with the assistance of response surface methodology. Under the optimal conditions, the developed method has been successfully applied to determine the rhodamine B in food samples. The linearities and limits of detection of rhodamine B in hot pepper, red wine, and chili powder samples were measured. Satisfactory recoveries in the range of 94.8-103.3% with relative standard deviations <5.5% were obtained. Investigation of the adsorption mechanism of magnetic polyimide composite indicated that multiple interactions, including hydrophobic, π-π, and hydrogen bonding interactions, were involved in the adsorption process.

Visual Biopsy by Hydrogen Peroxide-Induced Signal Amplification.

Visual biopsy has attracted special interest by surgeons due to its simplicity and practicality; however, the limited sensitivity of the technology makes it difficult to achieve an early diagnosis. To circumvent this problem, herein, we report a visual signal amplification strategy for establishing a marker-recognizable biopsy that enables early cancer diagnosis. In our proposed approach, hydrogen peroxide (H2O2) was selected as a potential underlying marker for its compact relationship in cancer progression. For selective recognition of H2O2 in the process of visual biopsy, a benzylbenzeneboronic acid pinacol ester-decorated copolymer, namely, PMPC-Bpe, was synthesized, affording the final formation of the H2O2-responsive micelles in which amylose was trapped. The presence of H2O2 activates the boronate ester recognition site and induces it releasing abundant indicator amylose, leading to signal amplification. The indicator came across the solution of KI/I2 added to the sample, and the formative amylose-KI/I2 complex has a distinct blue color at 574 nm for visual amplification detection. The feasibility of the proposed method is demonstrated by visualizing the H2O2 content of cancer at different stages and three kinds of actual cancerous samples. As far as we know, this is the first paradigm to rationally design a signaling amplification-based molecular recognizable biopsy for visual and sensitive disease identification, which will extend new possibilities for marker-recognition and signal amplification-based biopsy in disease progressing.

Mechanisms insights into Cd passivation in soil by lignin biochar: Transition from flooding to natural air-drying.

Biochar shows great potential in soil cadmium pollution treatment, however, the effect and mechanisms of biochar on cadmium passivation (CP) during the long-term process of soil from flooding to natural air-drying are not clear. In this study, a 300-day experiment was conducted to keep the flooded water level constant for the first 100 days and then dried naturally. Mechanisms of CP by lignin biochar (LBC) were analyzed through chemical analysis, FTIR-2D-COS, EEMs-PARAFAC, ultraviolet spectroscopy characterizations, and microbial community distribution of soil. Results showed that application of LBC results in rapid CP ratio in soil within 35 days, mainly in the residual and Fe-Mn bound states (total 72.80%). CP ratio further increased to 90.89% with water evaporation. The CP mechanisms include precipitation, electrostatic effect, humus complexation, and microbial remediation by promoting the propagation of fungi such as Penicillium and Trichoderma. Evaporation of water promoted the colonization of aerobic microorganisms and then increased the degree of soil humification and aromatization, thereby enhancing the cadmium passivation. Simultaneously, the biochar could reduce the relative abundance of plant pathogens in soil from 1.8% to 0.03% and the freshness index (ß/α) from 0.64 to 0.16, favoring crop growth and promoting carbon sequestration and emission reduction.

Highly efficient Ni(II) adsorption by industrial lignin-based biochar: a pivotal role of dissolved substances within biochar.

In the context of carbon neutrality, promoting resource utilization of industrial alkali lignin addressing heavy metal pollution is crucial for China's pollution alleviation and carbon reduction. Microwave pyrolysis produced functionalized biochar from industrial alkali lignin for Ni(II) adsorption. LB400 achieved 343.15 mg g-1 saturated adsorption capacity in 30 min. Pseudo-second-order kinetic and Temkin isotherm models accurately described the adsorption, which was endothermic and spontaneous (ΔGÏ´ < 0, ΔHÏ´ > 0). Quantitative analysis revealed that both dissolved substances and carbon skeleton from biochar contributed to adsorption, with the former predominates (93.76%), including mineral precipitation NiCO3 (Qp) and adsorption of dissolved organic matter (QDOM). Surface complexation (Qc) and ion exchange (Qi) on the carbon skeleton accounted for 6.3%. Higher biochar preparation temperature reduced Ni(II) adsorption by dissolved substances. Overall, biochar which comes from the advantageous disposal of industrial lignin effectively removes Ni(II) contamination, encouraging ecologically sound treatment of heavy metal pollution and sustainable resource utilization.

Development and application of a new 25,27-bis(L-phenylalaninemethylester-N-carbonylmethoxy)-26,28-dihydroxy-para-tert-butylcalix[4]arene stationary phase.

A 25,27-bis(L-phenylalaninemethylester-N-carbonylmethoxy)-26,28-dihydroxy- para-tert-butylcalix[4]arene-bonded silica gel stationary phase was synthesized, structurally characterized and used for LC. Its separation mechanism was studied and compared with octadecyl-bonded stationary phase, as well as our previously prepared para-tert-butylcalix[4]arene-1,2-crown-4 stationary phase. Meanwhile, the chromatographic behaviors were investigated by using polycyclic aromatic hydrocarbons, monosubstituted benzenes, anilines, phenols, Tanaka tests solutes, fluoroquinolones, and flavonoids as probes. Mechanisms involved in the chromatographic separation included hydrophobic, π-π and π-electron transfer, hydrogen bonding, and inclusion interactions. Moreover, the column was successfully employed for the analysis of the illegal additive of melamine in milk product.

Antibacterial-renew dual-function anti-biofouling strategy: Self-assembled Schiff-base metal complex coatings built from natural products.

Marine biological fouling has caused huge economic losses and environmental problems. Therefore, it was essential to develop effectively environment-friendly biofouling resistance technology. Here, inspired by the natural module of bacterial secretions, animal and plant extracts, we synthesized Schiff based compounds through Tobramycin (TOB) from Streptomyces and Protocatechualdehyde (PR) from black fern. Furthermore, a dynamic self-renewal Schiff based metal composite coating- (Fe/TOB-PR)n was prepared via layer by layer self-assembly (LBL) method. It was proved to be a versatile coating, which could adhere to different types of substrates. Hydrolytic degradation tests showed that the degradation of the (Fe/TOB-PR)20 coating was regular and controlled. Moreover, compared with the blank glass substrate, the antibacterial rate of (Fe/TOB-PR)20 reached 97 % after 24 h, and the test further shows that the durability of the antibacterial performance benefits from the greater coating thickness. Such coatings displayed excellent anti-bacteria and anti-algae adhesion properties which was attributed to the renewal of the surface and the generation of antibacterial substance (TOB) in the coating. Further, the coating eventually degraded to natural micromolecule monomer, avoiding the occurrence of microplastics. It provides research ideas for fabricating environment-friendly anti-biofouling coatings.

Preparation and characterization of glucose-based covalent organic polymer coated silica as stationary phase for high-performance liquid chromatography.

Carbohydrate is a renewable, sustainable, hydrophilic, and biodegradable natural product, which is widely used in the field of adsorption. In this study, a glucose-based covalent organic polymer (COP) coated silica was fabricated by facile solvent knitting reaction between tetrabenzylglucose and silica-phenyl with anhydrous aluminum trichloride as catalyst, forming a core-shell stationary phase (donated as SiO2@COPBn-glu) for high performance liquid chromatography. The prepared SiO2@COPBn-glu was characterized by scanning electron microscopy, transmission electron microscopy, Fourier-transform infrared spectrometry, solid-state 13C nuclear magnetic resonance spectrometry, X-ray photoelectron spectroscopy, and N2 adsorption-desorption experiments. Owing to the coexistence of benzene units and alkyl, hydroxyl and ether groups in the skeleton of COPBn-glu shell, the developed chromatographic packing exhibited reversed-phase/hydrophilic interaction mixed-mode with multiple retention mechanisms, such as hydrophobic, π-π, hydrogen bonding, and electron donor-acceptor interactions. The results revealed that the SiO2@COPBn-glu column demonstrated excellent selectivity and retention behavior for both hydrophilic and hydrophobic compounds with good repeatability and stability. Meanwhile, the chromatographic performance of the prepared SiO2@COPBn-glu column was compared with a C18 column to assess the role of the coating COPBn-glu shell. Therefore, the development of the SiO2@COPBn-glu stationary phase expands the potential application of COPs in separation field.

Simultaneous extraction of hydroxylated polycyclic aromatic hydrocarbons and catecholamines with magnetic boronic acid hypercrosslinked polymers.

Urinary hydroxylated polycyclic aromatic hydrocarbons (OH-PAHs) and catecholamines (CAs) are important biomarkers of PAHs exposure. In this study, a novel magnetic boronic acid hypercrosslinked composite (Fe3O4@HCP-BA) is synthesized using a facile one-pot strategy and applied as a sorbent for the simultaneous extraction of OH-PAHs and CAs in urine samples. The synthesized Fe3O4@HCP-BA composites are characterized by rich pore structure, highly specific surface area, good magnetic response, and excellent selectivity and adsorption efficiency (range: 65.26-496.71 and 1227.3-1581.8 µmol g-1 for CAs and OH-PAHs, respectively). The mechanisms governing the adsorption of the OH-PAHs and CAs to the Fe3O4@HCP-BA composites were systematically studied via adsorption kinetics, isotherm models, XPS characterization, and molecular simulation. The resultant Fe3O4@HCP-BA composite-based MSPE/HPLC-FLD method exhibited good linearity (R2 > 0.9916), low limits of detection (0.2-0.3 pg mL-1 and 0.2-0.3 ng mL-1 for OH-PAHs and CAs, respectively), and good precision (intra-day and inter-day RSDs < 11.1%). The analysis of CAs and OH-PAHs in the urine samples from 14 smokers and 14 non-smokers revealed a positive correlation between the concentrations of CAs and OH-PAHs. Our findings not only establish the proposed method as a green, environmentally friendly, and simple strategy for preparing magnetic adsorbents, but also confirm it as a promising alternative method for accurate determination of OH-PAHs and CAs in biological samples.

A molecularly imprinted polymer based on functionalized multiwalled carbon nanotubes for the electrochemical detection of parathion-methyl.

A novel composite of vinyl group functionalized multiwalled carbon nanotubes (MWCNTs) molecularly imprinted polymer (MIP) was synthesized and applied as a molecular recognition element to construct an electrochemical sensor for parathion-methyl in this paper. The special molecular recognition properties of parathion-methyl mainly dominated by π-π, p-π interaction and hydrogen bonding formed among functional monomer, template and matrix. A series of electrochemical experiment results proved that the prepared material had good adsorption capacity and fast mass transfer rate to parathion-methyl. The good selectivity of the sensor allowed fine discrimination between parathion and paraoxon, which had similar structures to parathion-methyl. The response of the MIPs was linearly proportional to the concentration of parathion-methyl over the range of 2.0 × 10(-7) to 1.0 × 10(-5) mol L(-1) with a lower detection limit of 6.7 × 10(-8) mol L(-1) (S/N = 3). This sensor was also applied in the detection of parathion-methyl in pear and cucumber with average recoveries of between 94.9% and 106.2% (RSD < 5%) being obtained. The results mentioned above show that the novel electrochemical sensor is an ideal device for the real-time determination of parathion-methyl in real samples.

Robot Versus Fluoroscopy-Assisted Vertebroplasty and Kyphoplasty for Osteoporotic Vertebral Compression Fractures: A Systematic Review and Meta-analysis.

OBJECTIVE: This study aimed to conduct a systematic review and meta-analysis to compare the clinical results and complications of robot-assisted (RA) versus fluoroscopy-assisted (FA) percutaneous vertebral augmentation (PVA) in the treatment of osteoporotic vertebral compression fractures (OVCFs). METHODS: A comprehensive search of online databases including PubMed, Embase, Cochrane Library, web of science, and core journals of China National Knowledge Infrastructure were performed to identify related studies reporting the clinical results and complications of RA versus FA-assisted PVA in the treatment of OVCFs. The rate of bone cement leakage was used to assess the complications. After the surgery, the clinical findings were analyzed using the Visual Analog Scale scores and the Oswestry Disability Index scores. The surgical time, intraoperative fluoroscopy frequency, and x-ray exposure duration were used to evaluate the perioperative results. Forest plots were constructed to investigate the results. RESULTS: RA-PVA had a significantly lower bone cement leakage rate, shorter fluoroscopy frequency, and shorter radiation exposure time of doctors compared with FA-PVA. However, no significant differences were found between RA-PVA and FA-PVA in operative time and radiation exposure time of patients. Furthermore, no statistically differences were found between the 2 groups in Visual Analog Scale and Oswestry Disability Index scores after surgery. CONCLUSIONS: This meta-analysis showed that RA-PVA can reduce bone cement leakage rate, fluoroscopy frequency, and doctors' radiation exposure time. With the advancement of RA technology, we anticipate more high-quality randomized controlled trials of RA versus FA-PVA in the future to validate and update the results of this analysis.

Design novel three-dimensional network nanostructure for lubricant infused on titanium alloys towards long-term anti-fouling.

Titanium alloys, recognized as a marine material with great potential, are currently facing serious biofouling problems, which greatly limits its application range. To improve the antifouling performance of titanium alloys, three unique surface of three-dimensional network, grass-like and linear nanostructures were obtained on titanium alloys via hydrothermal treatment in this work. Further, slippery liquid-infused porous surfaces (SLIPSs) were fabricated on titanium alloys via infusing PFPE lubricant into these nanostructures. Water contact angles and sliding angles of SLIPSs were measured to evaluate the effect of nanostructures on the stability of PFPE lubricant layer. Anti-fouling capability of SLIPSs were investigated by quantifying the cells of chlorella and phaeodactylum tricornutum (P. tricornutum)adhered to titanium alloys. The results shows that all the SLIPSs exhibited remarkable inhibition capacity for the settlement of chlorella and P. tricornutum. Among them, the SLIPS with three-dimensional network nanostructure displayed the longest-term anti-fouling performance, and its reduction rate of P. tricornutum and chlorella reaching 77.2 % and 84.5 % after being cultivated for 21 days, respectively, indicating that there existed a positive correlation between the stability of lubricant layer in the artificial seawater and the antifouling effect.

3D Intelligent Scissors for Dental Mesh Segmentation.

Teeth segmentation is a crucial technologic component of the digital dentistry system. The limitations of the live-wire segmentation include two aspects: (1) computing the wire as the segmentation boundary is time-consuming and (2) a great deal of interactions for dental mesh is inevitable. For overcoming these disadvantages, 3D intelligent scissors for dental mesh segmentation based on live-wire is presented. Two tensor-based anisotropic metrics for making wire lie at valleys and ridges are defined, and a timesaving anisotropic Dijkstra is adopted. Besides, to improve with the smoothness of the path tracking back by the traditional Dijkstra, a 3D midpoint smoothing algorithm is proposed. Experiments show that the method is effective for dental mesh segmentation and the proposed tool outperforms in time complexity and interactivity.

Porous covalent triazine-terphenyl polymer as hydrophilic-lipophilic balanced sorbent for solid phase extraction of tetracyclines in animal derived foods.

A novel hydrophilic-lipophilic balanced (HLB) solid phase extraction sorbent, microporous covalent triazine-terphenyl polymer (CTPCC-TP) was successfully synthesized and applied for the cleanup and extraction of tetracycline drugs in animal derived food samples. The specific ratio of two monomers, hydrophilic triazine and lipophilic aromatic rings, endowed the new material with hydrophilic-lipophilic balanced character, which made it capable of extracting both polar and nonpolar analytes. Prior to solid-phase extraction, food samples were extracted by McIlvaine buffer and passed through the CTPCC-TP cartridge. The experimental parameters affecting extraction efficiency, including loading, washing and elution were investigated and optimized. With the use of high-performance liquid chromatography-UV detection, a method detection limit in the range of 8.0-16.8 µg kg-1 and good linearity (22.6-1500 µg kg-1) for the determination of the tetracyclines in animal derived food samples can be achieved. The relative standard deviations (RSDs) for five replicate extractions of the tetracyclines ranged from 4.8 to 8.2%. The method recoveries for spiked tetracyclines (100 and 1000 µg kg-1) in bovine milk, egg, chicken liver samples were in the range of 81.3-98.7% with RSDs ranging from 3.9 to 7.7%, respectively, depending on both the analytes and samples. The method was suitable for the determination of tetracyclines in animal derived food samples.

Primary M1 macrophages as multifunctional carrier combined with PLGA nanoparticle delivering anticancer drug for efficient glioma therapy.

Glioma remains difficult to treat because of the infiltrative growth of tumor cells and their resistance to standard therapy. Despite rapid development of targeted drug delivery system, the current therapeutic efficacy is still challenging. Based on our previous studies, macrophages have been proved to be promising drug carrier for active glioma delivery. To make full use of macrophage carrier, primary M1 macrophages were proposed to replace regular macrophage to deliver nanodrugs into glioma, because M1 macrophages not only have the natural ability to home into tumor tissues, but they also have stronger phagocytic capability than other types of macrophage, which can enable them to uptake enough drug-loaded nanoparticles for therapy. In addition, M1 macrophages are not easily affected by harsh tumor microenvironment and inhibit tumor growth themselves. In this study, M1 macrophage-loaded nanoparticles (M1-NPs) were prepared by incubating poly(lactide-co-glycolide) (PLGA) nanoparticles with primary M1 macrophages. In vitro cell assays demonstrated M1 macrophage still maintained good tumor tropism capability after particle loading, and could efficiently carry particles across endothelial barrier into tumor tissues. In vivo imaging verified that M1-NPs exhibited higher brain tumor distribution than free nanoparticles. DOX@M1-NPs (doxorubicin-loaded M1-NPs) presented significantly enhanced anti-glioma effect with prolonged survival median and increased cell apoptosis. In conclusion, the results provided a new strategy exploiting M1 macrophage as carrier for drug delivery, which improved targeting efficiency and therapeutic efficacy of chemodrugs for glioma therapy.

Polymeric ionic liquid based on magnetic materials fabricated through layer-by-layer assembly as adsorbents for extraction of pesticides.

In this study, layer-by-layer assembly of polyelectrolyte multilayer films on magnetic silica provided a convenient and controllable way to prepare polymeric ionic liquid-based magnetic adsorbents. The resulting particles were characterized by Fourier transform infrared spectroscopy, X-ray diffraction, transmission electron microscopy, and magnetic measurements. The data showed that the magnetic particles had more homogeneous spherical shapes with higher saturation magnetization when compared to those obtained by free radical polymerization method. This facilitated the convenient collection of magnetic particles, with higher extraction repeatability. The extraction performance of the multilayer polymeric ionic liquid-based adsorbents was evaluated by magnetic solid-phase extraction of four pesticides including quinalphos, fenthion, phoxim, and chlorpropham. The data suggested that the extraction efficiency depended on the number of layers in the film. The parameters affecting the extraction efficiency were optimized, and good linearity ranging from 2 to 250µgL-1 was obtained with correlation coefficients of 0.9994-0.9998. Moreover, the proposed method presented low limit of detection (0.5µgL-1, S/N=3) and limit of quantification (1.5µgL-1, S/N=10), and good repeatability expressed by the relative standard deviation (2.0%-4.6%, n=5). The extraction recoveries of four pesticides were found to range from 58.9% to 85.8%. The reliability of the proposed method was demonstrated by analyzing environmental water samples, and the results revealed satisfactory spiked recovery, relative standard deviation, and selectivity.

[Biocompatibility evaluation of nano TCP/gelatin/velvet antler polypeptide material].

OBJECTIVE: To evaluate the biocompatibility of a new nano TCP/gelatin/velvet antler polypeptide material. METHODS: The nano TCP/gelatin/velvet antler polypeptide material was prepared, and the amorphous was observed by scanning electron microscope. L929 and NIH/3T3 cell lines were cultured conventionally. Acute toxicity test, hemolysis test, cell proliferation and cytotoxicity test were used to evaluate the biocompatibility of the material. RESULTS: The composite microsphere material was about 10 microm in diameter and had good spherical geometry, high monodispersity with nanometer size holes on the surface. Toxic symptoms such as hyperspasmia, palsy and death did not appear during the observing stage in acute toxicity test. Maximum hemolysis rate of the material was less than 5% which met the requirement of hemolysis test standard as a medical material. Different concentrations of the materials leaching liquor could enhance the proliferation of NIH/3T3 cells, which showed the good biologic activity. Toxicity grade was 0, and the material was no cytotoxic. CONCLUSION: Nano TCP/gelatin/velvet antler polypeptide material has good biocompatibility.