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To explore the active polysaccharides from Dendrobium devonianum, a novel O-acetylmannan (DDP-1) with molecular weight of 117 kDa was isolated from D. devonianum. The chemical and instrumental analysis indicated that the DDP-1 was a homopolysaccharide containing a backbone chain composed of →4)-β-d-Manp-(1 → (71.4%) residue with internal →4)-2-O-acetyl-β-d-Manp-(1 → (14.2%), →4)-3-O-acetyl-β-d-Manp-(1 → (7.1%), and non-reducing end β-d-Manp-(1 → (7.3%) residues. Anticancer assay in vitro revealed that DDP-1 had anticancer activity against the growth of HepG2 and MCF-7 cancer cells. Moreover, cytokine secretion assays also presented that DDP-1 can promote cytokine production of TNF-α and IL-6 in THP-1 macrophage stimulated by PMA. Finally, the effects of isolation and purification on the microstructure of DDP-1 was studied by scanning electron microscope. The morphological features of DDP-1 indicated that DDP-1 hold high potential application in hydrophilic polymer materials., (Copyright © 2022. Published by Elsevier B.V.)

In this study, a strategy of improving imprinting performance was developed using an enhanced cooperation effect of functional monomers based on deep eutectic solvents (DESs) monomer for the specific enrichment of benzoylation modified peptides. Zinc acrylate and DESs monomers were used as binary functional monomers, and ethylene glycol dimethacrylate was used as the cross-linking agent with SGRGKbz as template to prepare an imprinted monolith. It was observed that the use of DESs monomer significantly improveed the affinity of benzoylation imprinted monolith and increased the adsorption capacity. Under optimal conditions, the recovery and imprinting factor (IF) of the imprinted monolith for SGRGKbz can reach 93.0% and 10.58, respectively. The average recovery of SGRGKbz extracted from the spiked histone digestion solution can reach 88.4% (n = 5, RSD = 3.4%). After treatment with the benzoylation imprinted monolith, 12 benzoylation modified peptides, 13 benzoylation modified sites and 12 benzoylation proteins could be identified in the digestion of mouse liver protein, while only one of each benzoylation modified peptide, benzoylation modified site and benzoylation protein could be identified in the untreated digestion of mouse liver protein. The results indicated that the prepared imprinted monolith using DESs-based functional monomer was an effective method to increase the affinity of the resulting MIP., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2022 Elsevier B.V. All rights reserved.)

A new dual-function enzyme reactor was prepared based on a dopamine/graphene oxide coated boron affinity monolithic column, which can be used for simultaneous protein enzymatic hydrolysis and glycopeptide enrichment. Firstly, a boron affinity monolithic column was prepared as the carrier for enzyme reactor. Secondly, the monolithic column was coated with dopamine/graphene oxide to provide higher specific surface area for the increase in the amount of trypsin bound. Then, dopamine can self-polymerize under alkaline conditions to produce multiple reaction sites. By the Schiff base reaction and Michael addition reaction with amino, sulfhydryl groups to trypsin, enzyme were immobilized on the boron affinity monolithic carrier. The enzyme activity was characterized by kinetic parameters maximum rate (V max ) of the enzyme reaction and Michaelis constant (K m ). K m of the dual-function enzyme reactors doped with PDA/GO and without PDA/GO were 34.37 and 120.93 mM, Vmax were 1.35 and 3.35 mM/min, respectively. The performance of the dual-function enzyme reactor was evaluated by protein extraction of mouse liver. After digested by the dual-function enzyme reactor, the number of peptides was 4,801, which was 960 more than the number of peptides in the solution digestion. At the same time, the dual-function enzyme reactor displayed the ability to capture cis-dihydroxy compounds specificly. A total of 55 glycopeptides were enriched in the dual-functional enzyme reactor, corresponding to 33 glycoproteins. The dual-function enzyme reactor provided repeatable performance and robust with long-term storage., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2022 Elsevier B.V. All rights reserved.)

Multi-template imprinting is one of the challenge for molecular imprinting since the selectivity and binding affinity for each analyte decrease significantly compared with the corresponding molecularly imprinting polymers (MIPs) against single template. In this work, molecular crowding effect was tried to remedy the problem of imprinting reduction caused by the competition of two templates. Methacrylic acid (ACR) was used as functional monomer, ethylene dimethacrylate (EDMA) as crosslinker, and polystyrene (PS) as macromolecular crowding agent. With levofloxacin (S-OFX) as the first template, a number of compounds with varied chemical structure were chosen as the second template to investigate the imprinting effect of dual-template. When S-OFX and naproxen (S-NAP) was used as the dual-template, the imprinting factor (IF) of the resulting MIP for S-OFX was 20.1 and IF for S-NAP was 10.9. In contrast, for the single-template MIPs, IF for S-OFX was 22.4, and IF for S-NAP was 11.9. As a comparison, the IF of the DT-MIP prepared in absence of PS was only 2.3 for S-OFX and 1.0 for S-NAP. To analyze recognition mechanism of the molecular crowding-based imprinting system, molecular dynamics simulations to the chain structure of PS and binding modes between template and functional monomers was conducted by NAMD software. All the results displayed that molecular crowding is a promising method to improve the affinity of the dual-template imprinted polymer., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2021 Elsevier B.V. All rights reserved.)

Microfluidic system with multi-functional integration of high-throughput protein/peptide separation ability has great potential for improving the identification capacity of biological samples in proteomics. In this paper, a sample treatment platform was constructed by integrating reversed phase chromatography, immobilized enzyme reactor (IMER) and imprinted monolith through a microfluidic chip to achieve the online proteins fractionation, denaturation, digestion and peptides enrichment. We firstly synthesized a poly-allyl phenoxyacetate (AP) monolith and a lysine-glycine-glycine (KGG) imprinted monolith separately, and investigated in detail their performance in fractionating proteins and extracting KGG from the protein digests of MCF-7 cell. The removal percentage of 94.6% for MCF-7 cell protein and the recovery of 90.8% for KGG were obtained. The number of proteins and peptides identified on this microfluidic platform was 2,004 and 8,797, respectively, which was 2.8-fold and 3.0-fold higher than that of untreatment sample. The time consumed by this platform for a sample treatment was about 9.6 h, less than that of conventional method (approximate 13.3 h). In addition, this platform can enrich some peptide fragments containing KGG based on imprinted monolith, which can be served for the identification of ubiquitin-modified proteomics. The successful construction of this integrated microfluidic platform provides a considerable and efficient technical tool for simultaneous identification of proteomics and post-translational modification proteomics information., (Copyright © 2020 Elsevier B.V. All rights reserved.)

Polycyclic aromatic hydrocarbon (PAH) contamination in agricultural soils (n = 41) along Shanghai road net was systematically investigated to characterize pollution distribution and to apportion sources. Total PAH (Σ 16 PAH) concentrations in roadside agricultural soils varied from 17.2 to 3775 ng/g with an average of 339 ± 594 ng/g, 43.9 % of which corresponded to weakly - heavily contaminated levels. The spatial distribution of pollution hotspots depended on heavy traffic volume and intensive industrial activities in adjacent areas. A positive matrix factorization receptor model identified that vehicle emission and combustion of coal, biomass and natural gas were the predominant sources, accounting for 66.0 % and 23.7 % of Σ 16 PAH loadings, respectively. Stable carbon isotope analysis was applied for the first time in seven sites with high Σ 16 PAH concentrations for tracing their unique sources. It was concluded that PAHs in the heavily contaminated soil site G18 predominantly came from vehicle emission sources, different from the six other sites controlled by coal-processing and biomass combustion sources. Future studies should focus on quantifying the source contribution of PAHs in roadside agricultural soils based on the combination of multi-isotope approaches due to the data overlap of δ 13 C in certain sources., (Copyright © 2020 Elsevier B.V. All rights reserved.)

An organic-inorganic hybrid monolith incorporated with titanium dioxide nanotubes (TNTs) and hydrophilic deep eutectic solvents (DESs) was prepared and evaluated by the isolation of proteins using solid phase microextraction. A typical polymerization system was composed of choline chloride/methacrylic acid (ChCl/MAA, DESs monomer), glycidyl methacrylate (GMA), as well as ethylene glycol dimethacrylate (EDMA) in the presence of TNTs. Then the epoxy groups on the surface of the resulting monolith were modified with amino groups. The synergistic effect of TNTs and DESs monomer to improve the enrichment performance of the sorbent significantly was demonstrated. Compared with the corresponding TNTs/DESs-free monolith, the recoveries of BSA and OVA were increased to 98.6% and 92.7% (RSDs < 2.0%), with an improvement of more than 60.0%. With a correlation coefficient of determination (R 2 ) higher than 0.9995, the enrichment factors (EFs) were 21.9-28.3-fold. In addition, the resulting monolith was further applied to specifically capture proteins from rat liver according to their pI value, followed by HPLC-MS/MS analysis. The results indicated that the developed monolith was an effective material to isolate protein species of interest according to the pI value of target proteins., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2020 Elsevier B.V. All rights reserved.)

A monolithic chip incorporated with graphene oxide (GO) based on deep eutectic solvents (DESs) was developed for solid phase extraction (SPE). The carboxylated GO was modified with p-aminostyrene (pAS) by amidation, and the obtained GO (pAS-COOH-GO) was covalently incorporated into poly(butyl methacrylate-co-ethylene glycol dimethyl methacrylate) monolithic chip. Due to the high viscosity characteristics of DESs, a uniform pAS-COOH-GO incorporated monolithic chip with good permeability can be achieved. A systematic study of the preparation parameters on the performance of the resulting monolith was carried out, including the content of pAS-COOH-GO, DESs composition and porogen ratio. The resulting pAS-COOH-GO incorporated monolith was characterized by nitrogen adsorption, scanning electron microscopy, and transmission electron microscopy. The GO-doped monolithic chip can be used for SPE of polycyclic aromatic hydrocarbons (phenanthrene, anthracene, fluoranthene, pyrene, benzo(a)anthracene, benzo(a) pyrene, dibenzo(a,h)anthracene and inden(1,2,3,-cd)pyrene). The recoveries were all higher than 90%, which was about twice as high as that of the monolithic chip prepared without GO. By comparing the SPE results with that of GO free monolithic chip, good enrichment effects were demonstrated on the pAS-COOH-GO incorporated monolithic chip., (Copyright © 2019 Elsevier B.V. All rights reserved.)

In this study, a monolithic enzyme reactor based on a strategy of green synthesis was successfully prepared in a capillary with trypsin immobilized by "thiol-ene" click reaction. A polymer of poly(butyl methacrylate-co-α-methacrylic acid-co-ethylene glycol dimethacrylate) was prepared in a mixture of 1-butyl-3-methylimidazolium tetrafluoroborate and choline chloride/ethylene glycol as the support of enzyme reactor. After "thiol-ene" reaction was used for enzyme immobilization, the Michaelis constants and maximum reaction rate of the resulting immobilized enzyme reactors (IMER) were determined by capillary electrophoresis to be 2.1 mmol/L and 0.028 μmol/min, respectively. The enzymatic hydrolysis of the enzyme reactor under different experimental conditions were investigated. A on-line digestion of bovine serum albumin (BSA) on the new IMER can be achieved within 50 s, up to 864 times faster than in-solution digestion (12 h). BSA can be well digested and the numbers of identified peptides were 73 with the coverage rates of 82.7%. The IMER was further used for the analysis of protein extracts from rat liver, and 1034 protein groups were identified. All these results demonstrated that such a click reaction based IMER would be of great prospect in the high throughput analysis for proteome with high confidence., (Copyright © 2019. Published by Elsevier B.V.)

One of the major drawbacks of conventional molecularly imprinted polymers (MIPs) is the requirements of volatility porogenic solvent during polymerization. To overcome the default, MIP based on deep eutectic solvent (DES, a new type of green designer solvents) has been synthesized successfully. To improve the affinity of the MIP based on DES, in this work, a strategy of metallic pivot was suggested in the first time to prepare a highly selective MIP monolithic column. A cetirizine-imprinted polymer was prepared in a DES-based porogen system composed of choline chloride/ ethylene glycol (ChCl-EG) in the presence of Co(Ac) 2 as metallic pivot. The resulting DES- Co 2+ -MIP monolith had 23.5 times higher imprinting factor than the Co 2+ -free MIP monolith. The characterization of polymers indicated that DES was one of the primary factor influencing the MIP morphology and pore structure. Compared with previous metal-mediated and ionic liquid-based imprinted polymers, the introduction of DES as a porogen in polymerization led to higher imprinting factor (approximately 2.9 - 17.1 times). In addition, the resulting DES-Co 2+ -MIP can be used as an adsorbent for extraction of cetirizine from ethanol solution with the recoveries of 97.8%. As a conclusion, the metallic pivot is a rather valuable strategy for the synthesis of DES-based MIP monolith with high selectivity., (Copyright © 2019 Elsevier B.V. All rights reserved.)

A novel boronate affinity monolithic capillary was prepared by in-situ polymerization and successfully applied to microextraction (PMME) of glycoproteins. Using functional monomer 3-(acrylamido)phenylboronic acid (AAPBA) and hydrophilic macromonomer oligo (ethylene glycol) methyl ether methacrylate (OEG), crosslinking monomer ethylene glycol dimethacrylate (EDMA) and binary porogens of n-propanol and 1,4-butanediol, poly(AAPBA-co-OEG-co-EDMA) monolith was made with uniform structure and good column permeability. Systematic optimization of preparation conditions were performed, including AAPBA content, the molar ratio of AAPBA to OEG, crosslinking monomer content, n-propanol content in binary porogens. The optimized OEG boronic monolithic column was characterized with infrared absorption spectroscopy, field emission scanning electron microscopy and N 2 adsorption experiment. In this study, extraction performance was tested by PMME of horseradish peroxidase (HRP) and ovalbumin (OVA). Compared with the corresponding OEG-free boronate monolith, the recovery of HRP and OVA was significantly improved to 97.51% and 93.97% (RSDs < 5.0%), respectively, which increased by 30.0%. Moreover, the newly developed monolith was further applied for extraction of HRP and OVA from the egg white samples with the recovery of 96.10% and 92.24% (RSDs < 7.5%), respectively. The results suggested that the introduction of hydrophilic macromonomer into boronic material is an effective method to improve the affinity of boronate affinity chromatography to glycoproteins., (Copyright © 2018 Elsevier B.V. All rights reserved.)

A novel arabinogalactan (MOP-1) was isolated from leaves of Moringa oleifera and was purified by macro-porous resin, DEAE-52 Cellulose and Sepharose 6B gel filtration chromatography. High performance gel permeation chromatography (HPGPC) analysis showed that the molecular weight of MOP-1 was 7.65 × 10 7  Da. Monosaccharide composition analysis indicated that sugar composition is Rha: Ara: Gal in a molar ratio of 1:7.32:12.12. Structural analysis indicated that MOP-1 has a backbone of →1)-β-d-Galp-(3,4→ with highly branched chains at O-4 position. The branches were composed of →1)-β-d-Galp-(4→, →1)-α-d-Galp-(2→, Araf-(1→, Galp-(1→. Its antioxidant activities were evaluated by DPPH radical scavenging capacity, 2,2'-Azinobis-(3-ethylbenzthiazoline-6-sulphonate) (ABTS) radical cation scavenging capacity, and ferric-reducing antioxidant power (FRAP). The results indicated MOP-1 exhibited significant antioxidant activities., (Copyright © 2018 Elsevier B.V. All rights reserved.)

Aims: Dendrobium candidum (DC) and black tea, are traditional chinese drinks, which contain multiple active ingredients. However, whether or not the combination of these two ingredients can improve osteoporosis remains unknown. This study therefore aimed to examine the effects of the combination of DC and black tea extract (BTE) on osteoporosis., Main Methods: Ovariectomy (OVX)-induced osteoporosis in vivo as well as receptor activator of NF-κB ligand (RANKL)-induced osteoclastogenesis in vitro was selected., Key Findings: Results showed that OVX rats that were treated orally with a DC and BTE combination for 12 weeks maintained their calcium (Ca) and phosphorus (P) homeostasis and exhibited significantly enhanced estradiol (E 2 ) and OPG levels. This combination treatment also simultaneously reduced levels of interleukin (IL)-1β, IL-6 and improved the organ coefficients of the uterus and femur as well as BMD and BMC in OVX rats. In addition, this DC and BTE combination suppressed osteoclast differentiation in the RANKL-stimulated osteoclastogenesis of RAW 264.7 cells and effectively inhibited the expression of osteoclast-associated genes and proteins. The results of this study further highlight the fact that a combination of DC and BTE improved ovariectomy-induced osteoporosis in rats and suppressed RANKL-stimulated osteoclastogenesis in RAW 264.7 cells., Significance: This combination also significantly alleviated osteoporosis when compared to the alternative sole treatments above, due to synergistic effects among components. One partial mechanism of this combination might be the inhibition of osteoclast proliferation and the regulation of NFATC1/c-Fos expression., (Copyright © 2018 Elsevier Inc. All rights reserved.)

In this work, a hybrid monolith incorporated with graphene oxide (GO) was prepared in the first time with binary green porogens of deep eutectic solvents (DESs) and room temperature ionic liquids (RTILs). GO was modified with 3-(trimethoxysilyl) propylmethacrylate (γ-MPS), and the resultant GO-MPS can be incorporated into poly (methacrylic acid-co-butylmethacrylate-co-ethylene glycol dimethacrylate) monoliths covalently. A hybrid monolithic column with high permeability and homogeneity can be achieved due to good dispersion of GO-MPS in the green solvents. The GO-MPS incorporated monolith was characterized by transmission electron microscopy, scanning electron microscopy, thermogravimetric analysis and nitrogen adsorption tests. The separation of small organic molecules of alkylphenones and alkylbenzenes was used to evaluate the performance of GO-MPS grafted monolith. The GO-MPS grafted monolith displayed the maximum column efficiency of 147,000 plates/m, about twice higher than the GO-free monolith. In addition, all of the retention and selectivity of small molecules of alkylphenones and alkylbenzenes increased due to the addition of GO-MPS. The results demonstrated that the use of DESs and RTILs is a powerful approach for the preparation of GO incorporated polymer monoliths. The monolith was further applied to the separation of tryptic digests from bovine serum albumin, and the result indicated its potential in the analysis of some complex samples., (Copyright © 2017 Elsevier B.V. All rights reserved.)

A hybrid monolith incorporated with mesoporous molecular sieve MCM-41 of uniform pore structure and high surface area was prepared with binary green porogens in the first time. With a mixture of room temperature ionic liquids and deep eutectic solvents as porogens, MCM-41 was modified with 3-(trimethoxysilyl) propyl methacrylate (γ-MPS) and the resulting MCM-41-MPS was incorporated into poly (BMA-co-EDMA) monoliths covalently. Because of good dispersibility of MCM-41-MPS in the green solvent-based polymerization system, high permeability and homogeneity for the resultant hybrid monolithic columns was achieved. The MCM-41-MPS grafted monolith was characterized by scanning electron microscopy, energy dispersive spectrometer area scanning, transmission electron microscopy, FT-IR spectra and nitrogen adsorption tests. Chromatographic performance of MCM-41-MPS grafted monolith was characterized by separating small molecules in capillary electrochromatography, including phenol series, naphthyl substitutes, aniline series and alkyl benzenes. The maximum column efficiency of MCM-41-MPS grafted monolith reached 209,000 plates/m, which was twice higher than the corresponding MCM-41-MPS free monolith. Moreover, successful separation of non-steroidal anti-inflammatory drugs and polycyclic aromatic hydrocarbons demonstrated the capacity in broad-spectrum application of the MCM-41-MPS incorporated monolith. The results indicated that green synthesis using room temperature ionic liquid and deep eutectic solvents is an effective method to prepare molecular sieve-incorporated monolithic column., (Copyright © 2016 Elsevier B.V. All rights reserved.)

A new lanthanide metal-organic frameworks NKU-1 have successfully incorporated into poly (BMA-co-EDMA) monolith and evaluated by capillary electrochromatography (CEC). Lanthanide metal-organic frameworks [Eu2(ABTC)1.5(H2O)3(DMA)] (NKU-1) were synthesized by self-assembly of Eu(III) ions and 3,3',5,5'-azo benzene tetracarboxylic acid ligands have been fabricated into poly(BMA-co-EDMA) monoliths. 1-Butyl-3-methylimidazolium tetrafluoroborate and N,N-dimethylformamide were developed as binary porogen obtaining homogeneous dispersibility for NKU-1 and high permeability for monolithic column. The successful incorporation of NKU-1 into poly(BMA-co-EDMA) was confirmed and characterized by FT-IR spectra, scanning electron microscopy, X-ray diffraction, energy dispersive spectrometer area scanning, and transmission electron microscopy. Separation ability of the NKU-1-poly (BMA-co-EDMA) monoliths was demonstrated by separating four groups of analytes in CEC, including alkylbenzenes, polycyclic aromatic hydrocarbon, aniline series and naphthyl substitutes. Compared with bare monolithic (column efficiency of 100,000plates/m), the NKU-1-poly (BMA-co-EDMA) monoliths have displayed greater column efficiency (maximum 210,000plates/m) and higher permeability, as well as less peak tailing. The results showed that the NKU-1-poly (BMA-co-EDMA) monoliths are promising stationary phases for CEC separations., (Copyright © 2016 Elsevier B.V. All rights reserved.)

In this work, an efficient method to prepare polymer monoliths with incorporated carbon nanotubes in a mixture of room temperature ionic liquid and deep eutectic solvents was developed. With assistance of the binary green solvent, 1-butyl-3-methylimidazolium tetrafluoroborate and choline chloride/ethylene glycol, single-walled carbon nanotubes were dispersed successfully in pre-polymerization mixture without need of oxidative cutting of carbon nanotubes, which may allow depletion of the emission of volatile organic compounds into environment. The novel single-walled carbon nanotubes monolith was evaluated by capillary electrochromatography. Compared with the monolith made without single-walled carbon nanotubes, the monolith with the incorporation of single-walled carbon nanotubes exhibited high column efficiency (251,000plates/m) in the chromatographic separation. The morphology of the monolith can be tuned by the composition of mixture of ionic liquids and deep eutectic solvents to afford good column permeability and excellent separation ability for small molecules of alkyl phenones and alkyl benzenes. The results demonstrated that the method is a green strategy for the fabrication of multifunctional polymer monoliths., (Copyright © 2016. Published by Elsevier B.V.)

Polyhedral oligomeric silsesquioxane (POSS) was successfully applied, for the first time, to prepare imprinted monolithic coating for capillary electrochromatography. The imprinted monolithic coating was synthesized with a mixture of PSS-(1-Propylmethacrylate)-heptaisobutyl substituted (MA 0702), S-amlodipine (template), methacrylic acid (functional monomer), and 2-methacrylamidopropyl methacrylate (crosslinker), in a porogenic mixture of toluene-isooctane. The influence of synthesis parameters on the imprinting effect and separation performance, including the amount of MA 0702, the ratio of template to monomer, and the ratio of monomer to crosslinker, was investigated. The greatest resolution for enantiomers separation on the imprinted monolithic column prepared with MA 0702 was up to 22.3, about 2 times higher than that prepared in absence of the POSS. Column efficiency on the POSS-based MIP coatings was beyond 30,000 plate m(-1). The comparisons between MIP coating synthesized with the POSS and without the POSS were made in terms of selectivity, column efficiency, and resolution. POSS-based MIP capillaries with naproxen or zopiclone was also prepared and separation of enantiomers can be achieved., (Copyright © 2016 Elsevier B.V. All rights reserved.)

A neutral heteropolysaccharide (DOP-1-1) consisted by mannose and glucose (5.9:1) with an average molecular weight at about 1.78×10(5) Da was purified from Dendrobium officinale. Based on Fourier transform infrared spectrum (FT-IR) and nuclear magnetic resonance (NMR) spectra, it suggested that partial structure of DOP-1-1 is an O-acetylated glucomannan with β-d configuration in pyranose sugar forms. The immunomodulatory activity of DOP-1-1 was evaluated by secretion level of cytokine (interleukin (IL)-1β and IL-10) and tumor necrosis factor (TNF)-α in vitro. Our results suggested that DOP-1-1 could stimulate cytokine production (TNF-α, IL-1β) in cells. These findings demonstrated that the purified polysaccharide from D. officinale presented significant immune-modulating activities. Furthermore, by Western-blot we can found that the signaling pathways of DOP-1-1 induced immune activities involving ERK1/2 and NF-кB. As to antioxidant activity, DOP-1-1 hadn't showed remarkable scavenging capacity of 1,1-diphenyl-2-picrylhydrazyl radical (DPPH) in contrast with other studies of polysaccharides from D. officinale., (Copyright © 2015 Elsevier B.V. All rights reserved.)

Polyhedral oligomeric silsesquioxane (POSS) was successfully applied, for the first time, to prepare imprinted monolithic column with high porosity and good permeability. The imprinted monolithic column was synthesized with a mixture of PSS-(1-Propylmethacrylate)-heptaisobutyl substituted (MA 0702), naproxon (template), 4-vinylpyridine, and ethylene glycol dimethacrylate, in ionic liquid 1-butyl-3-methylimidazolium tetrafluoroborate ([BMIM]BF4). The influence of synthesis parameters on the retention factor and imprinting effect, including the amount of MA 0702, the ratio of template to monomer, and the ratio of monomer to crosslinker, was investigated. The greatest imprinting factor on the imprinted monolithic column prepared with MA 0702 was 22, about 10 times higher than that prepared in absence of POSS. The comparisons between MIP monoliths synthesized with POSS and without POSS were made in terms of permeability, column efficiency, surface morphology and pore size distribution. In addition, thermodynamic and Van Deemter analysis were used to evaluate the POSS-based MIP monolith., (Copyright © 2015 Elsevier B.V. All rights reserved.)

Through precipitation polymerization, three monodisperse molecularly imprinted polymers (MIPs) containing imprints of 2,4-diamino-6-methyl-1,3,5-triazine (DM), cyromazine (CY) or trimethoprim (TM), were synthesized using methacrylic acid as functional monomer, divinylbenzene as cross-linker, and a mixture of acetonitrile-toluene (90/10, v/v) as porogen. The morphology and selectivity of the MIPs were characterized and compared systematically. The MIPs had the best specific binding in pure acetonitrile, and the data of adsorption experiment were fitted well with Langmuir and Freundlich model. In addition, DM-MIPs showed the excellent binding and multi-recognition capability for CY, melamine (ME), triamterene (TA) and TM, and the binding capacity were 7.18, 7.56, 5.66 and 5.45μmol/g, respectively. Due to the pseudo template and the ability of multi-recognition, DM-MIPs as sorbent material could avoid the effect of template leakage on quantitative analysis. Therefore, DM-MIPs were used as a solid-phase extraction material to enrich ME, CY, TA and TM from different bio-matrix samples for high performance liquid chromatography analysis. Under the optimized conditions, the recoveries of three spiked levels in different bio-matrix samples were ranged from 80.9% to 91.5% with RSD≤4.2 (n=3)., (Copyright © 2015 Elsevier B.V. All rights reserved.)

Supermacroporous poly(methacrylic acid-butyl methacrylate-ethylene glycol dimethacrylate) monoliths with the pore size up to 5-10 μm were successfully prepared in a ternary polymeric porogens utilizing viscoelastic effect. High concentration (over 20 mg/mL) of polystyrene (PS) in porogen was used to achieve the desirable characteristics of the monolithic capillary. Modification of the co-porogen composition, i.e., the content of dimethyl sulfoxide and isooctane, enabled tailoring of the supermacropore structure with a wide range of pore size. The effects of the amount of polymer porogen and molecular weights of PS on the formation of supermacropore were also studied. In preliminary applications, the separations of alkyl phenones and alkylbenzenes were achieved on the supermacropore columns using a mode of capillary electrochromatography. The study demonstrated successfully the ability of polymer porogen to form supermacropore monolith via viscoelastic phase separation., (Copyright © 2014 Elsevier B.V. All rights reserved.)

In this work, molecularly imprinted polymer (MIP) nanoparticles were prepared at a low level of crosslinking in the presence of liquid crystalline monomer as physical crosslinker to replace the most of chemical crosslinker. The imprinted nanoparticles against d-zopiclone were synthesized by precipitation polymerization using a mixture of methacrylic acid, ethylene glycol dimethacrylate, and liquid crystalline monomers. The resulting d-zopiclone imprinted nanoparticles were evaluated in capillary electrochromatography by partial filling technique. The resolution of enantiomer separation achieved on the d-zopiclone-imprinted nanoparticles was up to 3.29 and the column efficiency of zopiclone enantiomer (up to 66,900 plates/m) with good peak symmetry was obtained. The imprinted nanoparticles prepared in the presence of liquid crystalline monomer can retain affinity and specificity for template even when prepared with a level of cross-linker as low as 5%., (Copyright © 2013 Elsevier B.V. All rights reserved.)

One of the main challenges in MIPs preparation is the proper MIP monolith design for water-soluble compounds due to the difficulty in satisfying the demands of both good column permeability and affinity to polar template. A new strategy of metallic pivot in a ternary porogenic system of dimethyl sulfoxide (DMSO)-dimethylformamide (DMF)-1-butyl-3-methylimidazolium tetrafluoroborate ([Bmim]BF4) was suggested to solve this problem. An imprinted monolithic column with high porosity and good permeability was synthesized using a mixture of methyl gallate (template), 4-vinylpyridine, ethylene glycol dimethacrylate, and cobalt acetate. Some polymerization factors, such as template-monomer molar ratio and the composition of the ionic liquid, on the imprinting effect of the resulting MIPs monoliths were systematically investigated. In a mobile phase of acetonitrile-buffer, the greatest imprinting factor of 10.9 was obtained on the MIPs monolith with the optimized polymerization parameters. Thermodynamic analysis for separation demonstrated that the separation between the template and its analogs on the ion-mediated MIPs monolith is an enthalpy-controlled process., (Copyright © 2013 Elsevier B.V. All rights reserved.)

The combination of microparticles of molecularly imprinted polymers (MIPs) with partial filling capillary electrochromatography (CEC) has previously been demonstrated for the enantiomer separation. In this paper, precipitation polymerization was used to prepare d-zopiclone imprinted nanoparticles (50-80 nm) by a strategy of the dilution of pre-polymerization mixtures. The influence of some important parameters on the preparation of MIPs nanoparticles, including template to monomer ratio, type and amount of cross-linking monomer, and functional monomer composition ratio were investigated. In addition, the effect of separation condition, e.g., organic modifier content, pH value and salt concentration of buffer, on the electrochromatographic behavior of the MIP nanoparticles were studied. In spite of lower selectivity factor (1.11), high column performance (theoretical plates 41,400) of template was obtained and the resolution of enantiomers separation was 4.75 under the optimized conditions. Compared to the previously reported MIP microparticles, the MIP nanoparticles showed good peak symmetry and an ability of high speed separation (<15 min) in CEC mode., (Copyright © 2012 Elsevier B.V. All rights reserved.)

Molecular crowding is a new approach to promoting molecular imprinting more efficiently. In this work, this concept was applied to the preparation of imprinted monoliths in the presence of molecular crowding agent for stabilizing binding sites and improving molecular recognition. The imprinted monolithic column was synthesized using a mixture of enrofloxacin (template), methacrylic acid, ethylene glycol dimethacrylate, and polystyrene (molecular crowding agent). Some polymerization factors, such as template-monomer molar ratio and the composition of the porogen, on the imprinting effect of resulting MIP monolith were systematically investigated. Moreover, a stoichiometric displacement model for retention was successfully applied to evaluate the interaction between the solute and the stationary phase. Compared with the MIP prepared by conventional polymerization, the molecular crowding-based monolithic MIPs showed higher selectivity. The results suggested that molecular crowding is a powerful strategy to increase the effect of molecular imprinting., (Copyright © 2012 Elsevier B.V. All rights reserved.)

Low loading capacity is the main problem of molecularly imprinted stationary phase, which is attributed to the high level of crosslinking restricting distortion phenomena of polymer backbone in molecular imprinting. A new approach based on liquid crystal with recognition ability is demonstrated for synthesis of molecularly imprinted polymer coatings in a low level of crosslinking. The resulting low crosslinking (20%) open-tubular imprinted capillary was able to separate enantiomers by means of capillary electrochromatography. The resolution of enantiomer separation achieved on the (S)-amlodipine-imprinted capillary was up to 6.36 in less than 2.5 min. The strong recognition ability with a selectivity factor of 1.81 and high column performance of template (up to 23,300 plates/m) were obtained. Performance of imprinting comparable to that recorded in conventional MIP stationary phase was observed. The liquid crystal MIP coatings were also prepared using either (S)-naproxen or (S)-ofloxacin as template molecule. The resolutions of enantiomers separation were 1.41 and 1.55, respectively. The results illustrate that the synthesis of low crosslinking MIP coatings based on liquid crystal is not only an experimental-simplified process of high performance, but also an approach to produce chiral stationary phase comparable to other chiral stationary phases., (Copyright © 2012 Elsevier B.V. All rights reserved.)

Molecular crowding is a new approach to promoting molecular imprinting more efficiently. In this work, this concept was applied to the preparation of low cross-linked imprinted polymers in the presence of an immobilised template for stabilizing binding sites and improving molecular recognition. An imprinted monolithic column was synthesized using a mixture of 2,4-diamino-6-methyl-1,3,5-triazine (template), 2,4-diamino-6-(methacryloyloxy) ethyl-1,3,5-triazine (polymerisable template), methacrylic acid, ethylene glycol dimethacrylate, and polystyrene (molecular crowding agent). Some polymerization factors, such as template-monomer molar ratio, the composition of the porogen and crosslinking density, on the imprinting effect of resulting MIP monolith were systematically investigated. The results indicated that the imprinted monolithic columns prepared in the presence of molecular crowding agent retained affinity and specificity for template even when prepared with a level of cross-linker as low as 9%. Moreover, a stoichiometric displacement model for retention was successfully applied to evaluate the interaction between the solute and the stationary phase. Compared with the low cross-linked MIP prepared by conventional polymerization, the molecular crowding-based low cross-linked monolithic MIPs showed higher selectivity. The results suggested that molecular crowding is a powerful strategy to increase the effect of molecular imprinting at a low level of crosslinker., (Copyright © 2011 Elsevier B.V. All rights reserved.)

This report provided the first example of using pivot concept to prepare monolithic molecularly imprinted polymers (MIPs) with ketoprofen (KET) imprints, in which metal ions were employed as mediator between the functional monomer and the template to achieve higher fidelity of imprint. To solve metal ions in pre-polymerization system, a new ternary porogen of dimethyl sulfoxide-toluene-isooctane was developed for preparation of MIP monoliths with high porosity and good permeability. The effect of polymerization parameters such as the nature of metal ions, the ratio of template to metal ion and the degree of crosslinking, on the permeability, morphology and affinity of the metal ion mediated MIP monolith were studied. The experiments demonstrated that Ni(2+), Co(2+) and Zn(2+) can be applied as pivot to prepare KET-imprinted monolith. Relative to monolithic MIP without metal ions, all the ion-mediated macropore MIP monoliths showed enhanced permeability, capacity factor and selectivity factor. High permeability (1.06×10(-7)mm(2)) was obtained on the Co(2+)-mediated MIP monolith and great selectivity factor (3.84) was achieved on the Ni(2+)-mediated one. The stoichiometric displacement model was constructed to investigate the recognition mechanism of metal-ion mediated MIP. The results indicate that metal ion as pivot not only improves the affinity but also allows the fine-tuning on the macroporous structure of MIP monolith., (Copyright © 2011 Elsevier B.V. All rights reserved.)

One monomer molecularly imprinted polymer coatings were first synthesized in fused silica capillary columns with 2-methacrylamidopropyl methacrylate (MAM) as single functional monomer in addition to a cross-linking monomer. Since MAM may generate no or little EOF, a strategy of precursor of polymerization, which does not interfere with the formation of defined imprints, was used to introduce an ionizable functional monomer to generate a stable electroosmotic flow for electrochromatography (CEC) by post-polymerization hydrolization. The resulting MAM-based open-tubular imprinted capillary was able to separate enantiomers by means of CEC. The resolution of enantiomers separation achieved on S-amlodipine-imprinted capillary was up to 16.1. The strong recognition ability (selectivity factor was 3.23) and high column performance (theory plates was 26,053 plates m(-1)) of template were obtained. The MIP coatings were also prepared using either S-naproxen or S-ketoprofen as template molecule. The resolutions of enantiomers separation were 2.20 and 4.56, respectively. The results illustrate that the synthesis of MIP using one monomer is not only an experimental-simplified process, but also an approach to producing chiral stationary phase with high efficiency and selectivity., (Copyright © 2011 Elsevier B.V. All rights reserved.)

Background: Real-time quantitative TRAP assays for detection of telomerase activity have been recently developed to eliminate complex post-PCR procedures. However, all of them use the conventional TRAP assay that possesses an unpredictable cascade of events in PCR amplification caused by stagger annealing, which may affect the accuracy of quantitation., Methods: A novel RTQ-TRAP method was developed by combining the duplex scorpion with modified TP-TRAP assay that has high fidelity PCR amplification of the telomerase product (DS/TP-TRAP). The synthesized oligonucleotide that represents telomerase products is used to set up a standard curve., Results: The DS/TP-TRAP method gives the standard curve a dynamic range of 6 orders of magnitude (R(2)=0.9992). It optimizes PCR amplification efficiency and determines telomerase activity in a lower threshold cycle number (Ct value). The method is both accurate and reproducible to measure telomerase activity in human tumor cell lines, and linearity from 1 to 1000 cells could be obtained (R(2)=0.9926). For tumor samples, the results determined by the DS/TP-TRAP assay are comparable to the data obtained with the conventional TRAP method., Conclusions: The DS/TP-TRAP assay provides a high sensitive and accurate method for real-time quantitative detection of telomerase activity. It is thus a potential robust tool for application in cancer molecular diagnostics.