RSC Advances
·
2016
·Vol. 6
·期 92
·89484-89491
·
IF 3.289
Yingshuai Liu,Jin Xie,Zeying Zhang,Zhisong Lu
O-GlcNAcylation is a very important post-translational modification of nucleocytoplasmic proteins. Aberrant O-GlcNacylation has been found in a variety of human diseases including many types of cancers, diabetes, and Alzheimer's disease. However, analysis of protein O-GlcNacylation still remains a great challenge due to its low levels and labile nature. Herein, a highly sensitive and reliable colorimetric method is developed by use of wheat germ agglutinin (WGA) lectin for specific recognition of O-GlcNAc and gold nanoparticle (AuNP)-catalyzed copper deposition for signal amplification. In presence of the target molecule, AuNP is specifically introduced onto the sensing surface and then catalyzes the copper deposition. An Au@Cu core–shell structure is produced from the deposition. The obtained copper shell on AuNP is dissolved by FeCl3 due to the oxidation–reduction reaction between copper and Fe3+, resulting in Cu2+ and Fe2+, which subsequently form a red coordination complex in the presence of bathophenanthrolinedisulfonic acid disodium salt (BPT2−). Thus, the amount of the red complex is proportional to the level of O-GlcNAc. Qualitative O-GlcNAc detection is realized by direct readout with the naked eye, while the quantitative analysis is achieved by measurement of the absorbance using a UV-Vis spectrophotometer. With increasing time, more and more copper is deposited on the surface of AuNP, thus achieving significant signal amplification. Under optimal conditions, an ultralow limit of detection (LOD) down to 0.02 pg mL−1 is achieved with GlcNAc-conjugated BSA as a model analyte. The developed platform was also successfully applied to analyze O-GlcNAcylation levels in prostate cancer cell line PC-3 and normal cell line RWPE-1. The results obtained by the proposed method are in good agreement with the data from protein microarray assays, demonstrating its great potential for sensitive and reliable O-GlcNAcaylation detection in fundamental research and in cancer diagnosis.
✓ 已验证
产品关联
DOI
高影响因子
Frontiers in Plant Science
·
2016
·
IF 4.495
Xu Huanhuan,Wang Ya,Chen Yana,Zhang Pan,Zhao Yi,Huang Yewei,Wang Xuanjun,Sheng Jun
Galloylated catechins, as the main secondary metabolites in the tea plant, including (-)-epigallocatechin-3-gallate and (-)-epicatechin-3-gallate, comprise approximately three-quarters of all the tea plant catechins and have stronger effects than non-galloylated catechins, both on the product quality in tea processing and the pharmacological efficacy to human beings. The subcellular localization of galloylated catechins has been the primary focus of studies that assess biosynthesis and physiological functions. Classical histochemical localization staining reagents can not specifically detect galloylated catechins; thus, their subcellular localization remains controversial. In the present study, we generated a monoclonal antibody (mAb) against galloylated catechins, which can be used for the subcellular localization of galloylated catechins in the tea plant by immunohistochemistry. Direct ELISA and ForteBio Octet Red 96 System assay indicated the mAb could recognize the galloylated catechins with high specificities and affinities. In addition, tea bud was ascertained as the optimal tissue for freezing microtomic sections for immunohistochemistry. What’s more, the high quality mAbs which exhibited excellent binding capability to galloylated catechins were utilized for the visualization of them via immunohistochemistry. Our findings demonstrated that vacuoles were the primary sites of localization of galloylated catechins at the subcellular level.
✓ 已验证
产品关联
DOI
PubMed
高影响因子
ANALYTICAL CHEMISTRY
·
2016
·
IF 5.886
Jian Sun,Bin Wang,Xue Zhao,Zong-Jun Li,Xiurong Yang
We demonstrate a rationally designed fluorescent and colorimetric dual-readout strategy for the highly sensitive, quantitative determination of inorganic pyrophosphatase (PPase) activity, a key hydrolytic enzyme involved in a variety of metabolic processes. Inspired by the selective oxidative and chromogenic reaction of o-phenylenediamine (OPD) with Cu2+, the special inhibitory effects of pyrophosphate (PPi) on the oxidative ability of Cu2+, and the specific hydrolysis of PPi into orthophosphate by PPase, a convenient small molecule OPD-based analytical system was developed for Cu2+/PPi recognition and PPase activity assay. We have confirmed that Cu2+ acts as the oxidant in the reaction and the main chromogenic product of OPD is 2,3-diaminophenazine (usually called OPDox) in the assay by combining the ESI-MS, 1H NMR, and XPS spectra analysis. Direct electrochemical insights into the Cu2+-triggered and PPi-inhibited mechanism were performed by cyclic voltammetry characterizations of the Cu2+ in the absence and presence of PPi for the first time. Furthermore, the proposed analytical system with clear response mechanism exhibits a promising outlook for the PPase activity assay in real biological samples and inhibitor screening.
✓ 已验证
产品关联
DOI
PubMed
高影响因子
JOURNAL OF SEPARATION SCIENCE
·
2017
·Vol. 40
·期 23
·4653-4660
·
IF 2.557
Haoran Fan,Jinpeng Wang,Qingran Meng,Yaoqi Tian,Xueming Xu,Zhengyu Jin
Photoirradiation surface molecularly imprinted polymers for the separation of 6- O -α- d -maltosyl-β-cyclodextrin were synthesized using functionalized silica as a matrix, 4-(phenyldiazenyl)phenol as a light-sensitive monomer, and 6- O -α- d -maltosyl-β-cyclodextrin as a template. Fourier transform infrared spectroscopy results indicated that 4-(phenyldiazenyl)phenol was grafted onto the surface of functionalized silica. The obtained imprinted polymers exhibited specific recognition toward 6- O -α- d -maltosyl-β-cyclodextrin. Equilibrium binding experiments showed that the photoirradiation surface molecularly imprinted polymers obtained the maximum adsorption amount of 6- O -α- d -maltosyl-β-cyclodextrin at 20.5 mg/g. In binding kinetic experiments, the adsorption reached saturation within 2 h with binding capacity of 72.8%. The experimental results showed that the adsorption capacity and selectivity of imprinted polymers were effective for the separation of 6- O -α- d -maltosyl-β-cyclodextrin, indicating that imprinted polymers could be used to isolate 6- O -α- d -maltosyl-β-cyclodextrin from a conversion mixture containing β-cyclodextrin and maltose. The results showed that the imprinted polymers prepared by this method were very promising for the selective separation of 6- O -α- d -maltosyl-β-cyclodextrin.
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Nanoscale
·
2017
·Vol. 9
·期 44
·17593-17600
·
IF 7.367
Min Wang,Xiangqian Fan,Lingxia Zhang,Jianjun Liu,Beizhou Wang,Ruolin Cheng,Mengli Li,Jianjian Tian,Jianlin Shi
Porous activated carbons (PACs) are promising candidates to capture CO2 through physical adsorption because of their chemical stability, easy-synthesis, cost-effectiveness and good recyclability. However, their low CO2 adsorption capacity, especially low CO2/N2 selectivity, has limited their practical applications. In this work, an optimized PAC with a large specific surface area, a small micropore size, and a large micropore volume has been synthesized by one-step carbonization/activation of casein using K2CO3 as a mild activation agent. It showed a remarkably enhanced CO2 adsorption capacity as high as 5.78 mmol g−1 and an excellent CO2/N2 selectivity of 144 (25 °C, 1 bar). Based on DFT calculations and experimental results, the coexistence of adjacent pyridinic N and –OH/–NH2 species was proposed for the first time to make an important contribution to the ultra-high CO2 adsorption performance, especially CO2/N2 selectivity. This work provides effective guidance to design PAC adsorbents with high CO2 adsorption performance. The content of pyridine N combined with –OH/–NH2 was further elevated by additional nitrogen introduction, resulting in a further enhanced CO2 adsorption capacity up to 5.96 mmol g−1 (25 °C, 1 bar). All these results suggest that, in addition to the well-defined pore structure, pyridinic N with neighboring OH or NH2 species played an important role in enhancing the CO2 adsorption performance of PACs, thus providing effective guidance for the rational design of CO2 adsorbents.
✓ 已验证
产品关联
DOI
PubMed
高影响因子
JOURNAL OF SOLID STATE CHEMISTRY
·
2017
·
IF 2.299
Zhen Ge,Xin Li,Wenguo Zhang,Qili Sun,Chunpeng Chai,Yunjun Luo
In this paper, the ultrafine Fe-O compound/ammonium perchlorate (AP) nanocomposites were prepared via in-suit growth method. The structure and morphology of the nanocomposites were characterized by infrared spectra, X-ray diffraction (XRD), scanning electron microscopy (SEM), energy dispersion X-ray spectrometer (EDS) and transmission electron microscopy (TEM) test. The results showed that the prepared Fe-O compound nanoparticles were amorphous state and deduced as 2L-ferrihydrite. The size of Fe-O compound/AP nanocomposites could be effectively controlled by changing the recrystallization condition. 2L-ferrihydrite nanoparticles was evenly dispersed in the nanocomposites proved by EDS and TEM analysis. Furthermore, the thermal decomposition of Fe-O compound/AP nanocomposites was analysized by TG-DSC method. The prepared 2L-ferrihydrite nanoparticles of the nanocomposites showed good catalytic effect on AP because of their decreasing the decomposition temperature and increasing the total heat release of AP.
✓ 已验证
产品关联
DOI
高影响因子
FOOD HYDROCOLLOIDS
·
2017
·
IF 4.747
Ping Shao,Huiling Ma,Jieyu Zhu,Qiang Qiu
The aim of this research was to investigate the effect of ionic strength (Na + 0.1–0.5 mol/L, Ca 2+ 0.01–0.05 mol/L) on the physicochemical stability of o/w emulsions stabilized by Ulva fasciata polysaccharide . Droplet diameter, Polydispersity Index (PDI), zeta-potential value, microscopic morphology and rheological properties were achieved to investigate the possible stability mechanisms. The results showed that different metal ions had significant effects on the stability of o/w emulsions. When compared the effect of Ca 2+ with that of Na + , it was found that Na + concentration did not have a significant effect on emulsions stability. The results indicated that zeta-potential decreased sharply with increasing calcium ionic strength (CaCl 2 :0.01 mol/L - 0.05 mol/L) and the minimum zeta-potential value was −27.5 mV, while zeta-potential changed slightly when NaCl (0.1 mol/L - 0.5 mol/L) were added. As for z-average size and PDI, they changed significantly with higher valence metallic ions. With increasing NaCl and CaCl 2 concentration, the retention rate of R-(+)-Limonene was reduced and emulsions exhibited non-Newtonian behavior. Another interesting result was that the addition of Ca 2+ at low concentration (0.01 mol/L - 0.02 mol/L) managed to improve the stability of emulsions .
✓ 已验证
产品关联
DOI
高影响因子
ACS Catalysis
·
2016
·
IF 9.307
Nengchao Luo,Min Wang,Hongji Li,Jian Zhang,Huifang Liu,Feng Wang
One of the challenges of depolymerizing lignin to valuable aromatics lies in the selective cleavage of the abundant C–O bonds of β-O-4 linkages. Herein we report a photocatalytic oxidation–hydrogenolysis tandem method for cleaving C–O bonds of β-O-4 alcohols. The Pd/ZnIn2S4 catalyst is used in the aerobic oxidation of α-C–OH of β-O-4 alcohols to α-C═O with 455 nm light, and then a TiO2–NaOAc system is employed for cleaving C–O bonds neighboring the α-C═O bonds through a hydrogenolysis reaction by switching to 365 nm light. Interestingly, the oxidation–hydrogenolysis tandem reaction can be conducted in one pot to offer ketones and phenols (up to 90% selectivity) via a dual light wavelength switching (DLWS) strategy. EPR and metal loading experiments elucidate that Ti3+ in TiO2 is formed in situ and is responsible for the photocatalytic hydrogenolysis through electron transfer from Ti3+ to the β-O-4 ketones.
✓ 已验证
产品关联
DOI
高影响因子
BIOCHEMISTRY-MOSCOW
·
2015
·Vol. 80
·期 3
·379-389
·
IF 1.303
Zhao Shancheng,Deng Chao,Wang Zhen,Teng Liping,Chen Jinghua
The roles of sugar chains such as heparan sulfate (HS) in stem cell self-renewal and differentiation are poorly understood. HS is a sugar chain with linear sulfated polyanionic disaccharide repeating structures that interact with many proteins, including structural proteins in the extracellular matrix and growth factors and their receptors. Thus, unraveling the role of HS in stem cell self-renewal and differentiation could provide new insights and technical routes in clinical stem cell applications. Here, we purified rat bone marrow mesenchymal stromal cells (BMMSCs) by density gradient centrifugation, analyzed mesenchymal stromal cell surface stemness marker expression by flow cytometry, and identified the sulfotransferases responsible for sulfation ester modification of HS. An osteogenic differentiation model was established by chemical induction reagents and confirmed via alkaline phosphatase (ALP) activity detection and the expression of the osteogenic differentiation markers Runx2 and Ocn. The expression profiles of HS sulfotransferases in rat BMMSCs before and after osteogenic induction were detected by RT-PCR and Western blot. Cell spheroids were formed in both control and osteogenic culture systems when BMMSCs were grown to high confluence. We determined that this type of cell spheroid was a highly calcified nodule by histochemical staining. Among all the sulfotransferases examined, heparan sulfate 6-O-sulfotransferase 3 (HS6ST3) mRNA and protein were upregulated in these calcified cell spheroids. HS6ST3 knockdown BMMSCs were established with RNA interference, and they had significantly lower ALP activity and decreased expression of the osteogenic differentiation markers Runx2 and Ocn. These findings suggest that HS6ST3 is involved in BMMSC differentiation, and new glycotherapeutic-based technologies could be developed in the future.
✓ 已验证
DOI
PubMed
高影响因子
POLYMER BULLETIN
·
2014
·Vol. 71
·期 6
·1331-1347
·
IF 1.491
Yuan Mingwei,He Zhengguo,Li Hongli,Jiang Lin,Yuan Minglong
Ring-opening polymerization of l -lactic acid O -carboxyanhydride was catalyzed by 4-dimethylaminopyridine in the presence of polyols pentaerythritol (PER) or dipentaerythritol (DPE). A high yield and relatively high molecular weight of 4- or 6-arm star PLA were obtained. The reaction was observed to be conducted easily and controllably. NMR analysis revealed that the end of the star PLA chain is a hydroxyl group and the central core is a PER or DPE group. The crystallinity of star PLA is lower than that of linear PLA. The crystallinity of 4-arm star PLA is lower than that of 6-arm PLA. Compared with that of 4-arm star PLA, the molecular arrangement of 6-arm star PLA may be relatively more regular.
✓ 已验证
产品关联
DOI
高影响因子
Journal of Materials Chemistry A
·
2014
·Vol. 2
·期 33
·13277-13282
·
IF 0
Ru-Jun Chen,Mian Huang,Wen-Ze Huang,Yang Shen,Yuan-Hua Lin,Ce-Wen Nan
Li–La–Zr–O thin films were successfully fabricated using a sol–gel spin coating method, and the effects of altering the annealing temperature and the number of layers of the films on electrolyte conductivity were studied. Using X-ray diffraction, scanning electron microscopy and X-ray photoelectron spectroscopy, the characteristics of these films were investigated as a function of annealing temperature and the numbers of layers of the film. With these methods, an amorphous structure and a smooth surface on the films were revealed. The thin film's ionic conductivity was investigated by impedance analysis. The results show that the ionic conductivity of the films decreases with an increase of the annealing temperature, from 1.67 × 10−6 S cm−1 for 600 °C annealing to 8.53 × 10−7 S cm−1 for 800 °C annealing. The influence of film thickness on conductivity was investigated and the conductivity followed an inverse u-shaped curve with increasing film thickness. We propose that Li–La–Zr–O thin films may be promising solid electrolytes for solid-state lithium-ion batteries.
✓ 已验证
产品关联
DOI
SYNTHETIC METALS
·
2014
·
IF 2.222
Shuai Yan,Siwei Yang,Lin He,Caichao Ye,Xun Song,Fang Liao
In this paper, poly( o -phenylenediamine) quantum dots (PoQDs) with amorphous structures were synthesized via a simple hydrothermal treatment. The size of PoQDs can be easily controlled by changing the reaction time. All these quantum dots show excellent photoluminescent (PL) performance. The p– π * transition between N and conjugated system in PoQDs increased the quantum yield significantly. Further experiments suggested the existence of quantum size effect in amorphous structures for the first time. The controllable PL performance were closely related to the significant quantum size effect. What’s more, these PoQDs were low cost and have high anti-jamming performance, good stability and application perspective of fluorescent bio-imaging.
✓ 已验证
产品关联
DOI
高影响因子
危险品化学品经营许可证（带存储）