TALANTA
·
2018
·
IF 4.244
Wenya Feng,Juan Qiao,Dan Li,Li Qi
Utilizing block copolymers as coatings, a protocol of chiral ligand exchange capillary electrochromatography (CLE-CEC) protocol was designed and developed with dual ligands for D,L-amino acids enantioseparation. Four block copolymers including poly maleic anhydride- co -styrene- co -N-methacryloyl- L -histidine methyl ester [P(MAn-St-MAH)], poly maleic anhydride- co -styrene- co -N-methacryloyl- L -lysine methyl ester [P(MAn-St-MAL)], poly maleic anhydride- co -styrene- co -N-methacryloyl- L -phenylalanine methyl ester [P(MAn-St-MAP)] and poly maleic anhydride- co -styrene- co -N-methacryloyl- L -threonine methyl ester [P(MAn-St-MAT)] were synthesized by reversible addition fragmentation chain transfer polymerization reaction. Key factors affecting the enantioresolution were optimized, including the concentration of Zn (II) central ion, pH value of buffer solution and monomers of the block copolymers. The enantioresolution of the proposed CLE-CEC system could be enhanced dramatically by employing P(MAn-St-MAH) as the immobilized chiral ligand and by coordinating the synergistic effect of free ligand in buffer solution. The principle of improved enantioresolution of the CLE-CEC system with dual ligands was discussed. Well enantioseparation was successfully realized with 7 pairs of D,L-amino acids enantiomers baseline separation and 5 pairs part separation. For quantitative analysis of D, L -alanine, a good linearity was established in the range of 9.4 μM to 1.5 mM (r 2 = 0.997) with the limits of detection (LODs) 3.7 μM of D -alanine, 2.0 μM for L -alanine, and limits of quantification (LOQs) 9.0 μM for D -alanine and 6.0 μM for L -alanine. The peak area and migration time reproducibility (n = 6) were 4.1% and 3.5% for D -alanine, 3.7% and 3.1% for L -alanine. Further, the enzyme kinetics study of alanine aminotransferase was investigated with the constructed CLE-CEC system.
研究领域:
分析化学
·
生物化学
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产品关联
DOI
PubMed
高影响因子
CRYSTAL GROWTH & DESIGN
·
2020
·
IF 4.089
Jin-Xia Yang,Xin Zhang,Ye-Yan Qin,Yuan-Gen Yao
A 2D network of {[Zn(Hbcpt)(H2O)3]·7H2O} (1) was hydrothermally synthesized and structurally characterized. By employing different N-donor ligands into the system of 3,5-bis(4′-carboxyl-phenyl)-1,2,4-triazole (H3bcpt) and Zn(II) cations, six novel entangled coordination polymers, namely, {[Zn2(bcpt)(μ2-OH)(H2O)]·(py)·4H2O} (2), {[Zn2(Hbcpt)2(bpa)2]·2H2O} (3), {[Zn(Hbcpt)(bpp)]·[Zn(Hbcpt)(bpp)]·2.5H2O} (4), {[Zn5(bcpt)2(biimpy)2(μ2-OH)4]·5H2O} (5), {[Zn2(bcpt)(bib)(μ2-OH)]·H2O} (6), and {[Zn2(bcpt)(bix)4(μ2-OH)]·3H2O} (7) (H3bcpt = 3,5-bis(4′-carboxyl-phenyl)-1,2,4-triazole, bpa = 1,2-bis(4-pyridyl)ethane, bpp = 1,3-bi(4-pyridyl)propane, biimpy = 2,6-bis(imidazole-1-yl)pyridine, bib = 1,4-bis(N-imidazolyl)butane, bix = 1,4-bis(imidazol-1-ylmethyl)-benzene, py = pyridine), were obtained. Single-crystal X-ray diffraction analysis reveals that, with the different N-donor ligands, the resulting compounds present entangled structures with different topologies. Compound 1 shows a 2D (4, 4) network, and the adjacent sheets are extended into a 3D supramolecular framework via hydrogen-bonding interactions. Interesting, by introducing a series of ditopic N-donor ligands into the reaction system, compounds 2–7 with entangled structures were harvested. Compound 2 exhibits a 3D self-penetrating network with an 8-connected bcu topology. Compound 3 features an 8-fold dia network showing an unusual [4 + 4] mode of interpenetration. Compound 4 is comprised of two parts of undulated 2D 44-sql networks, and the adjacent undulated layers are parallel interpenetrated to each other to give a 2D → 3D polycatenated framework. Compound 5 presents an unusual 3D self-penetrating network with a novel 4,6,6-connected trinodal network with the point symbol of (32·4·52·6)(32·4·56·66}{32·56·66·7}. Compound 6 shows a 2-fold interpenetrating 3D architecture with 6-connected sxd topology. Compound 7 displays an unprecedented self-penetration derived from abnormal [3 + 2] 5-fold interpenetrating dia subnets. Structural diversity of these compounds suggests that different N-donor ligands can induce the organic ligand to present different conformations and coordination modes, and the influence on the final structures. Furthermore, the luminescent properties of compounds 1–7 have been investigated in the solid state.
研究领域:
配位化学
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材料科学
·
晶体学
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产品关联
DOI
高影响因子
TALANTA
·
2020
·
IF 5.339
Shimeles Addisu Kitte,Terefe Tafese,Chen Xu,Muhammad Saqib,Haijuan Li,Yongdong Jin
The development of highly sensitive electrochemiluminescence (ECL) immunosensors by using functional nanoparticles as signal amplifiers is a solution towards sensitive determination of many low concentration disease biomarkers. Herein, a sensitive aptamer-based, sandwich-type surface plasmon enhanced electrochemiluminescence (SPEECL) immunosensor was demonstrated for the detection of cardiac troponin I (cTnI), by means of aptamer conjugated CdS QDs and AuNPs as ECL luminophores and plasmon sources, respectively, in which Tro4 aptamer was used as a capture probe for cTnI and Tro6 aptamer as a detecting probe. The signal of the developed SPEECL system showed ~ 5-fold increment as compared to that of without AuNPs. Using this ECL platform for the detection of cTnI, a linear range and the limit of detection (LOD) were found to be 1 fg/mL - 10 ng/mL and 0.75 fg/mL, respectively.
研究领域:
分析化学
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生物化学
·
纳米技术
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生物医学工程
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心脏病学
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DOI
PubMed
高影响因子
JOURNAL OF COORDINATION CHEMISTRY
·
2021
·
IF 1.751
Le Guo,Yan-Peng Gao,Yan-Hua Lv,Li Wang,Yu Han,Fei Chang
We report the synthesis, crystal structures, and magnetic properties of a series of two-dimensional (2-D) and three-dimensional (3-D) coordination polymers (CPs). A solvothermal reaction of manganese metal salts with 4,4′-oxydibenzoic acid (H2oba), 4,4′-methylenebis(oxy) dibenzoic acid (H2mba), 4,4′-(propane-1,3-diylbis (oxy))dibenzoic acid (H2pba) or 1,4-bis (1H-imidazol-1-yl)-butane (bib) gives five new non-interpenetrating CPs, [Mn2(oba)2(CH3OH)(H2O)] (1), [Mn6(oba)6(bib)(DMF)2(H2O)4] · (DMF)2(CH3OH) (2), [Mn4(mba)4(bib)(CH3OH)] (3), [Mn7(pba)7 (bib)(H2O)4] · (H2O)3(DMA)(CH3OH)0.5 (4), and [Mn7(pba)7(H2O)6](DMA)3 (5). The X-ray crystal structural analyses revealed that 1, 4, and 5 are 2-D layers, whereas 2 and 3 are 3-D frameworks with 1-D Mn-carboxylate chains. In 1, 2, 4, and 5, the 1-D Mn-carboxylate chains are formed by flexible carboxylate ligands and Mn ions; these were then linked by organic ligands in different directions, leading to the formation of 2-D and 3-D frameworks. Furthermore, IR, PXRD, elemental analysis, TGA, and magnetic properties have been investigated.
研究领域:
无机化学
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材料科学
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固体化学
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DOI
高影响因子
BIOSENSORS & BIOELECTRONICS
·
2019
·
IF 9.518
Jiangle Yi,Zhen Liu,Jianhui Liu,Hanbiao Liu,Fangquan Xia,Dong Tian,Changli Zhou
A novel label-free electrochemical aptasensor was fabricated based on a three-dimensional porous electrode (3D-CS/rGO/GCE) for the detection of acetamiprid residues. The sensing signal was generated by the DNA itself. The porous electrode was prepared by electrodeposition in situ and characterized by scanning electron microscope (SEM), cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS). These results indicated that the porous electrode has a uniform nanoporous structure, high active area, and excellent conductivity , leading to improve the transmission efficiency of current signals. The 3D-CS/rGO/GCE was used to increase a load of acetamiprid aptamer on the electrode. Meanwhile, DNA self-assembly strategy was used to further increase the DNA amounts. Thus the electrochemical current was amplified significantly due to increased phosphate group amounts by the above synergistic effect . The determination of acetamiprid residues using square wave voltammetry (SWV) showed good sensitivity, with the linear range from 0.1 pM to 0.1 μM and the detection limit was 71.2 fM. The label-free electrochemical aptasensor was also used to detect acetamiprid residues in tea samples with satisfactory results.
研究领域:
分析化学
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环境科学
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食品科学
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DOI
高影响因子
JOURNAL OF FLUORESCENCE
·
2024
·
IF 2.6
Li Ling,Li Zheng-Ling,Wang Wei,Long Xin-Xin,Liu Ping,Wang Guo-Tian,Sun Shi-Qing,Du Rong-Lian
The rapid and accurate detection of programmed death-ligand 1 (PD-L1) expression is of great value in the diagnosis and treatment of tumors. ELISA-based traditional method is the gold standard for protein detection, but there are still some shortcomings, especially the antigen-antibody dependence, greatly increased the detection time and cost. This work constructed a label-free fluorescent probe for rapid and sensitive detection of PD-L1 using a truncated aptamer as recognition molecules and double-stranded DNA specific dyes (SYBR Green I) as signal units. After a series of optimization conditions, this probe has good detection capability for PD-L1 in buffer solution with the detection limit as low as 0.68 ng/mL. Due to the specific recognition ability of aptamer and target, this method also has good selectivity for PD-L1 detection. The recovery of PD-L1 in human serum samples ranges from 86.20 to 96.36%. Compared with other methods, this strategy does not need to be marked, and does not need other complex design and purification process, but simple operation process and strong anti-interference ability. The whole detection process can be completed within 20 min and has good application prospect. This work will provide reference for drug dosage and prognosis evaluation of specific tumor therapy.
研究领域:
癌症生物学
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分子诊断
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生物技术
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产品关联
DOI
PubMed
高影响因子
Food Analytical Methods
·
2018
·Vol. 11
·期 6
·1668-1676
·
IF 2.245
Jia Jie,Yan Shang,Lai Xiaoxia,Xu Yongzhen,Liu Tong,Xiang Yuhong
A facile colorimetric aptasensor based on unmodified gold nanoparticles (AuNPs) for rapid, highly sensitive and selective detection of malachite green (MG), one of triphenylmethane dyes and antibiotics, was successfully developed. Malachite green RNA aptamer having the binding ability with high affinity and specificity would be the ideal recognition receptor for MG. RNA aptamer can adsorb on the AuNPs and protect AuNPs against salt-induced aggregation. When malachite green were added in a solution, aggregation of AuNPs was specifically induced by desorption of aptamer from the surface of gold nanoparticles as the formation of aptamer-target complex. Therefore, the salt could trigger AuNP aggregate and the solution color changed from red to blue. The solution colors and absorbance were related with the concentrations of MG, and a well linear relationship in the wide range was obtained. The detection limit of MG was down to 15.95 nM. This colorimetric method was better than other traditional methods in terms of its reduced detection time, simple signal generation, high selectivity, lower detection limit, and observation with the naked eye. The proposed one-step, label-free method was successfully used to determine MG in actual fish samples. The high recoveries of MG in fish sample detection were satisfied.
研究领域:
分析化学
·
环境科学
·
纳米技术
·
食品安全
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产品关联
DOI
高影响因子
COLLOIDS AND SURFACES B-BIOINTERFACES
·
2017
·
IF 3.887
Jing Cao,Yahui Zhang,Yukun Wu,Jing Wu,Wei Wang,Qiang Wu,Zhi Yuan
It has been shown that multivalent ligands could significantly enhance the binding avidity compared with the monovalent ones; therefore, once incorporated into nanoparticles, they promote superior targeting ability without increasing the ligand density. Although ligand valency and density play a key role on the targeting ability of corresponding nanoparticles, these facotrs remain largely unexplored and detailed studies are lacking. Herein, a series of multivalent ligands with certain valencies (FA n , n indicates the valency of ligand: n = 3, 5, 7) has been conveniently synthesized by conjugating different copies of folate ligands with poly(acrylic acid) (PAA). Negatively charged chitosan nanoparticles (CTS-SA NPs) have been utilized as proper multivalent platforms because they can strongly suppress non-specific protein adsorption and cellular uptake without interfering with the targeting ability of multivalent ligands. Subsequently, the structure of CTS-SA NPs has been modified using different amounts of FA n to form multivalent nanoparticles (FA n -CTS-SA NPs) with various valencies and densities. A series of specific investigations of them suggested that the cellular uptake of multivalent nanoparticles has largely varied with the ligand valency variation even at similar ligand densities; and also largely varied with ligand density variation even at the same ligand valencies. The intermediate valency and density values determined in the current study ( ie., 5 and 2.4 wt%, respectively) have provided the best cellular uptake, facilitating superior targeting ability at relatively low ligand valency and density. Unexpectedly, no conspicuous difference has been observed during endocytotic inhibition assays with single inhibitors, which may be attributed to the synergetic endocytotic mechanism with multiple pathways of multivalent nanoparticles. The optimal multivalent nanoparticles have also exhibited excellent biocompatibility, long-term stability in vitro and enhanced circulation time in vivo , thus demonstrating their potential for targeted drug delivery.
研究领域:
纳米技术
·
药学
·
生物医学工程
·
药物递送系统
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产品关联
DOI
PubMed
高影响因子
JOURNAL OF ORGANIC CHEMISTRY
·
2024
·
IF 3.3
Zhikang Chen,Jiahao Liu,Weiying Ou,Terumasa Kato,Zhe Wang,Yong Chen,Yan Liu,Keiji Maruoka
A series of novel axially chiral pyridylidene amine (PYE) ligands has been developed, and their catalytic capability has been demonstrated in various highly efficient and enantioselective Pd-catalyzed asymmetric allylic substitutions. A density-functional theory (DFT) study explains the preferential enantiocontrol in the key transition states of the axially chiral PYE ligand-promoted Pd-catalyzed allylic alkylation.
研究领域:
有机化学
·
催化化学
·
理论化学
✓ 已验证
DOI
PubMed
高影响因子
Signal Transduction and Targeted Therapy
·
2024
·Vol. 9
·期 1
·1-13
·
IF 40.8
Yang Minghui,Li Chunhui,Ye Guoguo,Shen Chenguang,Shi Huiping,Zhong Liping,Tian Yuxin,Zhao Mengyuan,Wu Pengfei,Hussain Abid,Zhang Tian,Yang Haiyin,Yang Jun,Weng Yuhua,Liu Xinyue,Wang Zhimin,Gan Lu,Zhang Qianyu,Liu Yingxia,Yang Ge,Huang Yuanyu,Zhao Yongxiang
Emerging and recurrent infectious diseases caused by human coronaviruses (HCoVs) continue to pose a significant threat to global public health security. In light of this ongoing threat, the development of a broad-spectrum drug to combat HCoVs is an urgently priority. Herein, we report a series of anti-pan-coronavirus ssDNA aptamers screened using Systematic Evolution of Ligands by Exponential Enrichment (SELEX). These aptamers have nanomolar affinity with the nucleocapsid protein (NP) of Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and also show excellent binding efficiency to the N proteins of both SARS, MERS, HCoV-OC43 and -NL63 with affinity K D values of 1.31 to 135.36 nM. Such aptamer-based therapeutics exhibited potent antiviral activity against both the authentic SARS-CoV-2 prototype strain and the Omicron variant (BA.5) with EC 50 values at 2.00 nM and 41.08 nM, respectively. The protein docking analysis also evidenced that these aptamers exhibit strong affinities for N proteins of pan-coronavirus and other HCoVs (−229E and -HKU1). In conclusion, we have identified six aptamers with a high pan-coronavirus antiviral activity, which could potentially serve as an effective strategy for preventing infections by unknown coronaviruses and addressing the ongoing global health threat.
研究领域:
病毒学
·
分子生物学
·
药物开发
·
传染病
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产品关联
DOI
PubMed
高影响因子
JOURNAL OF FOOD COMPOSITION AND ANALYSIS
·
2022
·
IF 4.52
Yue Tang,Hongyan Yu,Xiaojuan Niu,Qiaodie Wang,Yuanyuan Liu,Yuangen Wu
Pesticide residues like carbendazim have always been a great threat to agricultural production and food safety. Herein, a fluorescent aptasensor for carbendazim detection was established based on aptamer-mediated quenching of gold nanoparticles (AuNPs) toward carbon dots (CDs). CZ-13 aptamer can wrap AuNPs and make them dispersed in salt solution, thus quench the fluorescence of CDs. On adding carbendazim, the aptamer is firstly consumed to preferentially combine with pesticides, resulting in the fluorescence recovery of CDs from quenching status. The degree of fluorescence recovery is positively correlated with pesticide concentration, which enables us to establish a fluorescence aptasensor for carbendazim detection. Under optimal conditions, the limit of detection of the fluorescent aptasensor is determined as low as 2.3 μg·L −1 . Moreover, the average recovery range of carbendazim in several vegetables and fruits is from 86 % to 99 %, indicating that such aptasensor may have bright application prospects for carbendazim detection in foods .
研究领域:
食品安全
·
分析化学
·
环境科学
✓ 已验证
产品关联
DOI
高影响因子
CATALYSIS LETTERS
·
2018
·Vol. 148
·期 9
·2709-2718
·
IF 2.911
Liu Zhenzhen,Shen Zhongquan,Zhang Ning,Zhong Wei,Liu Xiaoming
Abstract Homogeneous Cu(I)/NMI/TEMPO catalyst system (TEMPO = 2,2,6,6-tetramethylpiperidine-N-oxyl) has been investigated for its catalysis on the aerobic oxidation of 1-octanol and other alcohols into aldehydes under room temperature. The catalytic species was found to be a Cu(I) centre coordinated by two NMI molecules and other two weakly bound solvent molecules, [Cu(NMI) 2 (Sol) 2 ] + (Sol = solvent). When CuI was used, this species could be [Cu(NMI)I(Sol) 2 ]. Not like being speculated previously, NMI in this system acts solely as a ligand and its role coordinated to the copper centre enhanced the electron density on the metal centre which promoted the O 2 binding in the catalysis. The labile solvent binding to the Cu(I) centre is essential to ensure both oxygen and substrate binding. The catalyst system is suitable for the oxidation of various alcohols using a simple reaction setup and workup. In particular, the system possesses strong oxidizing capability in quantitative conversion of benzylic alcohols regardless of the substituents on the phenyl ring and allylic alcohols into aldehydes. A plausible mechanism was also proposed for the catalysis. Graphical Abstract The aerobic oxidation of primary alcohols at room temperature to corresponding aldehydes was achieved by the catalyst composed by Cu(I) and methyl imidazole (NMI) mediated by TEMPO in acetonitrile. The catalytic species is proposed to be such a Cu(I) complex that two of its four coordinating sites are occupied by a strong ligand(s) and the rest two are weakly bound by solvent molecules.
研究领域:
催化化学
·
有机合成
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）