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A rapid and sensitive method for analyzing trace β-blockers in complex biological samples,which involved magnetic solid-phase extraction(MSPE)coupled with Fourier transform ion cyclotron reso-nance mass spectrometry(FTICR-MS),was developed.Novel nanosilver-functionalized magnetic nano-particles with an interlayer of poly(3,4-dihydroxyphenylalanine)(polyDOPA@Ag-MNPs)were synthesized and used as MSPE adsorbents to extract trace β-blockers from biological samples.After extraction,the analytes loaded on the polyDOPA@Ag-MNPs were desorbed using an organic solvent and analyzed by FTICR-MS.The method was rapid and sensitive,with a total detection procedure of less than 10 min as well as limits of detection and quantification in the ranges of 3.5-6.8 pg/mL and 11.7-22.8 pg/mL,respectively.The accuracy of the method was also desirable,with recoveries ranging from 80.9％to 91.0％following the detection of analytes in human blood samples.All the experimental results demonstrated that the developed MSPE-FTICR-MS method was suitable for the rapid and sensitive analysis of trace β-blockers in complex biological samples.
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Prosthetic loosening and periprosthetic inflammation, as serious complications after joint replacement surgery, often require the secondary surgery for repair, which is easy to adversely affect the physical/mental health and economic status of patients.Studies have shown that the functional phenotype expressed by macrophages by different stimuli, namely macrophage polarization state, prolonged M1 polarization can lead to the continuation of long-term inflammation, while timely and effective M2 macrophage phenotype will lead to enhanced osteogenesis and tissue remodeling cytokine secretion and subsequent osseointegration, which play a crucial role in the development and outcome of prosthetic loosening and periprosthetic inflammation.The local micro-environment of extracellular matrix (ECM) is an important factor in the activation, migration, proliferation and fusion of macrophages. Researchers have deeply understood it mainly through the crosstalk between surface properties of biomaterials and macrophages. As an effector cell, macro-phages can perform complex spatiotemporal cellular functional responses by sensing the physical and chemical environment (surface topography, wettability, chemical composition, biological proteins) represented by surface properties of biomaterials.This paper summarizes the recent findings on macrophage polarization and material surface properties.
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Nanoparticles (NPs) have shown potential in cancer therapy, while a single administration conferring a satisfactory outcome is still unavailable. To address this issue, the dissolving microneedles (DMNs) were developed to locally deliver functionalized NPs with combined chemotherapy and photothermal therapy (PTT).
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RESUMO Este estudo investigou a eficiência da remoção de nitrato em meio aquoso usando adsorção em argilas montmorilonitas comerciais, comparativamente a uma resina aniônica comumente usada nessa operação. Algumas dessas argilas foram intercaladas como o íon hexadeciltrimetilamônio para avaliação. Áreas superficiais específicas, capacidades de troca catiônica e espectros de infravermelho médio foram obtidos para caracterização das argilas. Testes preliminares indicaram a nanoargila funcionalizada com aminopropiltrietoxisilano e octadecilamina como a mais eficiente na adsorção de nitrato, conquanto não tenha superado em eficiência a resina aniônica comercial também testada. Curvas cinéticas e isotermas de equilíbrio de adsorção de nitrato em fase aquosa na nanoargila e na resina comercial foram determinadas e modeladas para comparação, como também para seleção de modelos representativos e para estimativa de propriedades termodinâmicas dos sistemas estudados. Todos os ensaios foram realizados a 25°C e com pH neutro. Isotermas de equilíbrio também foram determinadas a 35 e 45°C. Os resultados obtidos mostram que o processo adsortivo estudado é físico, espontâneo e favorável tanto para a resina como para a nanoargila, as quais possuem muito boa afinidade com o nitrato. O modelo mais representativo para a cinética foi o de pseudossegunda ordem, enquanto para o equilíbrio foi a isoterma de Freundlich.
ABSTRACT This study investigated the efficiency of nitrate removal in aqueous medium using adsorption on commercial montmorillonites compared to an anionic resin widely used in this operation. Some of these clays were intercalated with hexadecyltrimethylammonium ion for this investigation. Specific surface areas, cation exchange capacities and mid-infrared spectra were determined for clays characterization. Preliminary tests indicated that the nanoclay functionalized with aminopropyltriethoxysilane and octadecylamine was the most efficient in nitrate adsorption, although it did not exceed anionic resin in efficiency. Adsorption kinetic and equilibrium of nitrate from aqueous phase on the nanoclay and anionic resin were determined and modeled for comparison, as well as for the selection of representative models and estimation of thermodynamic properties of the studied systems. All experiments were carried out at 25°C and at pH 7. Equilibrium isotherms were also determined at 35 and 45°C. The obtained results show that the adsorption processes studied are physical, spontaneous and favorable for both the resin and the nanoclay, which have very good affinity with nitrate. The most representative models for the systems were the pseudo-second order kinetic model and the Freundlich equilibrium isotherm.
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@#Functionalized graphene oxide is prepared based on graphene. It has attracted great interest from all over the world due to its good solubility, biocompatibility, high loading rate, and easy modification. This paper summarizes the surface modification of graphene oxide, and its applications on anti-tumor, antibacteria, anti-hypertension, gene therapy and biosafety as a drug carrier, providing new methods and ideas in the biomedical field.
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Objective: To study on the scavenging rules and optimum processing condition of heavy metals Pb, Cd, Hg, and Cu removal in Acanthopanax senticosus extract (ASE) with alkyl thiourea functionalized silica (ATFS). Methods: ASE was simulated as study object of excessive harmful elements Pb, Cd, Hg, and Cu.The scavenging mass, scavenging time, shaking speed and scavenging temperature were investigated by static scavenging way and the diameter ratio, sample solution, washing speed and washing temperature were investigated by dynamic scavenging way influence to metal removal rate. The best process of static and dynamic was chosen by orthogonal experiment; Eleutheroside B and eleutheroside E were as the effective constituents in ASE, solid contents and HPLC fingerprint similarity were as investigated index, the change of chemical composition in ASE to heavy metals removal from aqueous solution before and after treatment was evaluated. Results: Compared with unmodified silica gel (SG), static absorption and dynamic absorption had a high removal rate of heavy metals, the scavenging speed was relative fast, the best static scavenging process of harmful elements in ASE were: The ratio of TCME mass and adsorbent was 80∶1, shaking speed was 260 times/min, scavenging time was 600 min, scavenging temperature was 45 ℃; The best dynamic scavenging process: Diameter ratio was 1∶20, sample volume was 100 mL, washing speed was 3 BV/h, washing temperature was 15 ℃; The change rate of eleutheroside B and eleutheroside E before and after heavy metal elements in ASE dislodged were less than 2.00%, loss ratio of solid contents was 0.18%, fingerprint similarity was more than 99.9%. Conclusion: The method can be used to satisfy the high efficiency of selective removal of harmful elements in ASE and the effective composition of almost no effect, the method is simple and easy, so it can be recommended for pretreatment of harmful elements in traditional Chinese medicine extracts and this way provides a new thought and research technique to decrease the contents of harmful elements.
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A novel solid-phase extraction (SPE) adsorbent for simultaneous extraction of atrazine (ATZ) and its metabolites, deisopropylatrazine (DIA) and deethylatrazine (DEA) from environmental water samples was prepared. Polyacrylonitrile nanofibers (PAN NFs) mat was prepared via electrospinning, and was further functionalized to obtain polypyrrole modified polyacrylonitrile nanofibers (PPy-PAN NFs) mat, hydrazine modified polyacrylonitrile nanofibers (NH2-PAN NFs) mat and carboxyl modified polyacrylonitrile (COOH-PAN NFs) mat. The results showed that the adsorption capacity of COOH-PAN NFs mat was better than other three NFs mats in both static (2.0 mg/g) and dynamic (0.19 mg/g) experiments. Meanwhile, the runoff ratios of COOH-PAN NFs mat were the lowest (less than 30.0％) in the adsorption of three analytes, especially for high polar analytes, which showed that the hydrogen bond between carboxyl groups and analytes was the main interactive force. A combination of mat-based SPE and high performance liquid chromatography-diode array detection was further established for determination of 3 analytes in environmental water samples. The recoveries were 81.4％-120.3％ and the limits of detection were 0.12 ng/mL for DIA, 0.09 ng/mL for DEA and ATZ, respectively.
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To provide technical support for spider silk functional modification, we developed a simple and efficient functional platform via intein trans-splicing. Small ubiquitin-related modifier protein (SUMO) was fused to the recombinant spider silk protein (W2CT) by peptide bond via S0 split intein Ssp DnaB trans-splicing, resulting in a protein SUMOW2CT. However, incorporation of exogenous protein led to mechanical property defect and lower fiber yield, and also slowed down the fiber assembly velocity but no obvious differences in supercontraction and chemical resistance when compared with fibers from W2CT (W). SUMO protease digestion showed positive results on the fibers, indicating that the SUMO protein kept its native conformation and bioactive. Above all, this work provides a technical support for spider silk high simply and efficient functionalized modification.
Subject(s)
Animals , Inteins , Protein Splicing , Recombinant Proteins , Chemistry , Silk , Chemistry , Small Ubiquitin-Related Modifier Proteins , Chemistry , Spiders , Trans-SplicingABSTRACT
A benzyl functionalized ionic liquid, 1-benzyl-3-methylimidazolium bis [( trifluoromethyl ) sulfonyl]imide ([BeMIM][Tf2 N]), was synthesized and characterized as an extraction solvent of dispersive liquid-liquid microextraction ( DLLME) for enrichment and determination of 5 organophosphorus pesticides (phoxim, fenitrothion, chlorpyrifos, phorate and parathion) and 2 aromatic compounds (chloronaphthalene and anthracene) from environmental water samples by high-performance liquid chromatography ( HPLC). [BeMIM] [ Tf2 N] had higher extraction efficiency than 1-octyl-3-methylimidazolium bis [( trifluoromethyl) sulfonyl]imide and common organic solvents such as CCl4 and C2 Cl4 . The extraction was performed using 40 μL of [BeMIM][Tf2N] and 1 mL of methanol as extraction solvent and dispersive solvent respectively with centrifugal time of 5 min. Under the optimal conditions, the method proposed here provided a good linearity for all analytes with correlation coefficients between 0. 9994 and 0. 9998. The repeatability values, described as intra-day and inter-day relative standard deviations (RSDs) of five replicate experiments at three different concentrations of 10, 40 and 100 μg / L, were 1. 1% -4. 3% and 0. 8% -4. 8% , respectively. The limits of detection (LOD) were 0. 01 μg / L-1. 0 μg / L at a signal-to-noise ratio (S / N) of 3. This developed method was convenient and speedy, and could be employed to detect the analytes in three real environmental water samples with satisfactory relative recovery of 82. 7% -118. 3% and RSD of 0. 7% -5. 6% . Introduction of benzyl group into the imidazolium could obviously enhance the extraction efficiecny for analytes due to the π-πinteraction between [BeMIM] [ Tf2 N] and analytes. [ BeMIM] [ Tf2 N] was a satisfactory extraction solvent with a high enrichment factor of 339 and extraction efficiency of 81. 4% . Partition coefficients of all analytes in [BeMIM][Tf2 N]-DLLME system were determined and the extraction mechanism was discussed.
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The fourth generation poly( amidoamine) dendrimers ( G4. 0 PAMAM) functionalized multiwalled carbon nanotube ( G4 . 0-MWCNTs ) was prepared by amidation between carboxylated multiwalled carbon nanotube (MWCNTs) and G4. 0 PAMAM. Then a novel hydrogen peroxide (H2O2) sensor was fabricated by electrodepositing Pd nanoparticles (NPs) on a glassy carbon electrode (GCE) modified with G4. 0-MWCNTs composites. The modified electrode was characterized by field emission scanning electron microscopy ( FESEM) , cyclic voltammetry ( CV) and electrochemical impedance spectroscopy ( EIS) . A large amounts of highly dispersion PdNPs could be well loaded on the surface of the G4. 0-MWCNTs, and the modified electrode exhibited excellent electrocatalytic activity towards the reduction of H2 O2 . Under the optimized conditions, the reduction peak currents of H2 O2 were linear to their concentrations in the range from 1. 0 × 10-9 mol/L to 1. 0×10-3 mol/L and the limit of detection of 2. 3×10-8 mol/L was obtained. The recovery of standard addition for human serum samples was 96 . 7%-103 . 1%.
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OBJECTIVES: In this study, the effect of tube length and outer diameter (OD) size of hydroxylated-multi walled carbon nanotubes (OH-MWCNTs) on their uptake and toxicity was investigated in the nematode Caenorhabditis elegans using a functional mutant analysis. METHODS: The physicochemical properties of three different OH-MWCNTs were characterized. Uptake and toxicity were subsequently investigated on C. elegans exposed to MWCNTs with different ODs and tube lengths. RESULTS: The results of mutant analysis suggest that ingestion is the main route of MWCNTs uptake. We found that OH-MWCNTs with smaller ODs were more toxic than those with larger ODs, and OH-MWCNTs with shorter tube lengths were more toxic than longer counterparts to C. elegans. CONCLUSIONS: Overall the results suggest the aspect ratio affects the toxicity of MWCNTs in C. elegans. Further thorough study on the relationship between physicochemical properties and toxicity needs to be conducted for more comprehensive understanding of the uptake and toxicity of MWCNTs.
Subject(s)
Caenorhabditis elegans , Caenorhabditis , Carbon , Eating , Nanotubes, CarbonABSTRACT
OBJECTIVES: In this study, the effect of tube length and outer diameter (OD) size of hydroxylated-multi walled carbon nanotubes (OH-MWCNTs) on their uptake and toxicity was investigated in the nematode Caenorhabditis elegans using a functional mutant analysis. METHODS: The physicochemical properties of three different OH-MWCNTs were characterized. Uptake and toxicity were subsequently investigated on C. elegans exposed to MWCNTs with different ODs and tube lengths. RESULTS: The results of mutant analysis suggest that ingestion is the main route of MWCNTs uptake. We found that OH-MWCNTs with smaller ODs were more toxic than those with larger ODs, and OH-MWCNTs with shorter tube lengths were more toxic than longer counterparts to C. elegans. CONCLUSIONS: Overall the results suggest the aspect ratio affects the toxicity of MWCNTs in C. elegans. Further thorough study on the relationship between physicochemical properties and toxicity needs to be conducted for more comprehensive understanding of the uptake and toxicity of MWCNTs.
Subject(s)
Caenorhabditis elegans , Caenorhabditis , Carbon , Eating , Nanotubes, CarbonABSTRACT
A novel hydrogen peroxide sensor was fabricated by the seed-mediated growth method. First, polyethyleneimine(PEI) functionalized multiwalled carbon nanotubes(MWNTs) were used as growth scaffold on the glass carbon electrode ( GCE). Then, Au nanoparticles were electrodeposited uniformly as seeds. Finally, Pt nanoparticles ( PtNPs ) grew on Au nanoparticles to form Pt @ Au core-shell structure nanocomposite. A new type of electrochemical sensor based on Pt @ Au / PEI-MWNTs nanocomposites for detection of hydrogen peroxide was developed, and the designed Pt@ Au / PEI-MWNTs/ GCE was characterized by electrochemical methods and field emission scanning electron microscopy (FESEM). The Differential pulse experimental results showed that the modified electrode exhibited excellent electrocatalytic activity towards the reduction of H2 O2 with the wide linear range from 9. 2 ×10-8 mol/ L to 1. 3 ×10-3 mol/ L. The correlation coefficient was 0. 9994 and the low detection limit was 3. 1×10-8 mol/ L at the signal-to-noise of 3.
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High selectivity provided by biomolecules such as antibodies and enzymes has been exploited during the last two decades for development of biosensors. Of particular importance are efficient immobilization methods for biomolecules in order to preserve their biological activities. In this study, we have evaluated immobilization strategies for an anti-DNA antibody on a self-assembled monolayer of omega-functionalized thiols. The antibody was immobilized via peptide bond formation between the primary amines in the antibody and the carboxyl groups on the self-assembled monolayer. The peptide bond coupling was achieved by activating COOH groups on the surface through N-Hydroxysuccimide (NHS)-ester formation, followed by acylation of NH2 group in the antibody. DNA binding activity of the immobilized antibody was examined by counting beta emission from 35S-labeled DNA.