Publications by authors named "Sheng-Run Zheng"

31 Publications

Covalent Cross-Linking of Metal-Organic Cages: Formation of an Amorphous Cationic Porous Extended Framework for the Uptake of Oxo-Anions from Water.

Chempluschem 2021 Mar 18;86(5):699. Epub 2021 Mar 18.

School of Chemistry, South China Normal University, Guangzhou, 510006, P. R. China.

Invited for this month's cover are the collaborating groups of Sheng-Run Zheng and Wei-Guang Zhang from South China Normal University, China. The cover picture shows an amorphous cationic porous metal-organic material that constructed from the covalent linking of large cationic metal-organic cage for the removal of toxic oxo-anions from water with high capacities and rapid kinetics. Read the full text of the article at 10.1002/cplu.202000570.
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http://dx.doi.org/10.1002/cplu.202100056DOI Listing
March 2021

Covalent Cross-Linking of Metal-Organic Cages: Formation of an Amorphous Cationic Porous Extended Framework for the Uptake of Oxo-Anions from Water.

Chempluschem 2020 Nov 24;86(5):709-715. Epub 2020 Nov 24.

School of Chemistry, South China Normal University, Guangzhou, 510006, P. R. China.

Cationic amorphous metal-organic cage (MOC)-based materials capable of removing anionic pollutants from water are receiving increasing attention but they are still relatively less reported. Herein, for the first time, a cationic porous MOC-based extended framework, namely, CL-aMOC-1, was constructed by covalent linking of a cationic Pd L (L=3,5-di-pyridin-4-yl-benzaldehyde) cage with a 1,4-bis(4-aminophenyl)benzene (BAPB) linker. Interestingly, the reaction could be completed within 15 min using an amorphous MOC-based solid (aMOC-1) and BAPB as reactant via a low-temperature solid-state reaction. The CL-aMOC-1 showed improved stability, lower solubility and higher oxo-anion uptake in water compared with the original aMOC-1. The adsorption capacities for CrO , Cr O and ReO on CL-aMOC-1 were 245.1, 311.5 and 452.5 mg/g, respectively, in which the uptake of Cr(VI)-containing oxo-anions was among the highest compared with those of other metal-organic materials. The CL-aMOC-1 can selectively capture oxo-anions in the presence of competitive anions. It exhibits good reusability as over 85 % of the uptake capacity is retained after 5 cycles. Finally, it shows the ability to remove Cr(VI) ions from electroplating wastewater.
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http://dx.doi.org/10.1002/cplu.202000570DOI Listing
November 2020

A Mn(II)-MOF with inherent missing metal-ion defects based on an imidazole-tetrazole tripodal ligand and its application in supercapacitors.

Dalton Trans 2020 Sep;49(35):12150-12155

School of Chemistry, South China Normal University, Guangzhou, 510006, China. zhengsr-scnu.edu.cn wgzhang-scnu.edu.cn.

A metal-organic framework (MOF), namely SCNU-Z3, based on an imidazole-tetrazole tripodal ligand and Mn(ii), has been constructed. It exhibits a porous 3D framework composed of truncated octahedron cage subunits. Unexpected ligand-induced missing metal-ion defects were observed in the framework. In addition, the application of SCNU-Z3 in a supercapacitor was performed.
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http://dx.doi.org/10.1039/d0dt01666gDOI Listing
September 2020

A new QCM signal enhancement strategy based on [email protected] framework complex for miRNA detection.

Anal Chim Acta 2020 Jan 19;1095:212-218. Epub 2019 Oct 19.

School of Chemistry, South China Normal University, Guangzhou, 510006, China. Electronic address:

Sensitive and selective detection of miRNA is of great significance for the early diagnosis of human diseases, especially for cancers. Quartz crystal microbalance (QCM) is an effective tool for detecting biological molecules; however, the application of QCM for miRNA detection is still very limited. One of the great needs for QCM detection is to further improve the QCM signal. Herein, for the first time, we promote a new signal enhancement strategy for the detection of miRNA by QCM. First, a hairpin biotin-modified DNA was used as a probe DNA, which exposes the biotin site when interacting with target miRNA. Then, a [email protected] framework ([email protected]) complex formed by electrostatic attractions between SA and a MOF was introduced into the QCM detection system. The [email protected] complexes serve as both a signal amplifier and a specific recognition element via specific biotin-SA interactions. The strategy was applied to the detection of a colorectal cancer marker, miR-221, by using a stable Zr(IV)-MOF, UiO-66-NH. The detection linear range was 10 fM-1 nM, the detection limit was 6.9 fM, and the relative standard deviation (RSD) (n = 5) was lower than 10% in both simulated conditions and the real serum environment. Furthermore, the detection limit reached 0.79 aM when coupled with the isothermal exponential amplification reaction (EXPAR).
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http://dx.doi.org/10.1016/j.aca.2019.10.034DOI Listing
January 2020

The interaction of an amorphous metal-organic cage-based solid (aMOC) with miRNA/DNA and its application on a quartz crystal microbalance (QCM) sensor.

Chem Commun (Camb) 2020 Jan 12;56(4):591-594. Epub 2019 Dec 12.

School of Chemistry, South China Normal University, Guangzhou, 510006, China. zhengsr-scnu.edu.cn wgzhang-scnu.edu.cn.

The interaction between an aMOC and miRNA/DNA is studied and the use of a signal probe DNA (spDNA)@aMOC complex as an effective amplifier in a QCM sensor to detect miRNA is developed. The signal can be significantly enhanced, which leads to improved performance when detecting and distinguishing miRNAs.
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http://dx.doi.org/10.1039/c9cc08014gDOI Listing
January 2020

An unprecedented 2D covalent organic framework with an htb net topology.

Chem Commun (Camb) 2019 Nov 24;55(89):13454-13457. Epub 2019 Oct 24.

School of Chemistry, South China Normal University, Guangzhou 510006, P. R. China.

A 2D imine-linked COF with a hitherto unreported htb type topology was synthesized from a linear diamine linker and a judiciously designed tetra-aldehyde building block. This work opens the door to the development of COFs with unprecedented topologies and may broaden the scope of COF functional materials by pore size and pore surface engineering.
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http://dx.doi.org/10.1039/c9cc06780aDOI Listing
November 2019

Homochiral Cu(I) Coordination Polymers Based on a Double-Stranded Helical Building Block from Achiral Ligands: Symmetry-Breaking Crystallization, Photophysical and Photocatalytic Properties.

Inorg Chem 2019 Nov 14;58(21):14660-14666. Epub 2019 Oct 14.

School of Chemistry , South China Normal University , Guangzhou , 510006 , P. R. China.

A pair of homochiral coordination polymers, [Cu(DPT)] ( and , HDPT = 3,5-di-4-pyridinyl-2H-tetrazole), were assembled from achiral precursors. Crystal structure analysis showed that they are chiral three-dimensional (3D) coordination polymers based on a new double-stranded helical building block that is composed of two different 1D helices. Interestingly, rare symmetry-breaking crystallization was observed, in which the possibility of obtaining enantio-enriched bulk product with excessive enantiomers () was obviously higher than that for enantiomers () as demonstrated in multiple, repeated experiments with single-crystal diffraction and vibrational circular dichroism (VCD) spectra. Moreover, compound [Cu(DPT)] shows good chemical stability in water, with pH values ranging from 3 to 13, as well as in many common organic solvents. Photophysical properties, including thermochromic properties and two-photon excited luminescence, were studied, and the potential for applications in temperature sensing was exhibited. In addition, the photocatalytic degradation of methylene blue in water indicated that compound [Cu(DPT)] can be used as a photocatalyst.
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http://dx.doi.org/10.1021/acs.inorgchem.9b02341DOI Listing
November 2019

An Anionic Nanotubular Metal-Organic Framework for High-Capacity Dye Adsorption and Dye Degradation in Darkness.

Inorg Chem 2019 Oct 4;58(20):13979-13987. Epub 2019 Oct 4.

School of Chemistry , South China Normal University , Guangzhou , 510006 , P. R. China.

A metal-organic framework (MOF), named SCNU-Z2, based on a new heterotopic tripodal nitrogen-containing ligand, has been constructed. Due to the replacement of one imidazole group in the reported ligand with one tetrazole group, the charge of the framework is changed from cationic to anionic but retains the same framework structure. The framework consists of tubular channels with a diameter of 1.5 nm and exhibits satisfactory stability in water with a pH range of 3-11. The anionic nature of the framework allows the effective adsorption of the cationic dyes MLB, CV, and RhB with capacities of 455.6, 847.4, and 751.8 mg/g, respectively. Among them, the adsorption capacities for SCNU-Z2 on CV and RhB rank as the highest when compared with other reported MOFs. In contrast, SCNU-Z2 exhibits an extremely low capacity for anionic dyes MO and AO, making it useful for the separation of anionic and cationic dyes based on a charge-dependent mode. Interestingly, SCNU-Z2 can be used to degrade an anionic dye, MB, within 30 min under darkness at room temperature. The apparent activation energy of the dye degradation reaction is calculated to be approximately 18.96 kJ·mol, implying that the catalytic reaction of MB can be considered as a low-temperature thermocatalytic reaction in the dark/SCNU-Z2 system.
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http://dx.doi.org/10.1021/acs.inorgchem.9b01959DOI Listing
October 2019

Stable Hydrazone-Linked Covalent Organic Frameworks Containing O,N,O'-Chelating Sites for Fe(III) Detection in Water.

ACS Appl Mater Interfaces 2019 Apr 22;11(13):12830-12837. Epub 2019 Mar 22.

School of Chemistry and Environment , South China Normal University , Guangzhou 510006 , P. R. China.

Two stable crystalline hydrazone-linked covalent organic frameworks (COFs) (Bth-Dha and Bth-Dma) containing functional O,N,O'-chelating sites have been designed and successfully synthesized by the Schiff-base condensation reactions between benzene-1,3,5-tricarbohydrazide (Bth) and 2,5-dihydroxyterephthalaldehyde (Dha) or 2,5-dimethoxyterephthal-aldehyde (Dma), respectively. Bth-Dma exhibits strong fluorescence in the solid state and in an aqueous dispersion, while no fluorescence can be observed for Bth-Dha. Interestingly, the as-synthesized Bth-Dma can be used as a turn-off fluorescence sensor for the Fe(III) ion in aqueous solution with outstanding selectivity and sensitivity. The recognition process can be attributed to the coordination interaction between Fe(III) ion and the O,N,O'-chelating sites in the pore wall of Bth-Dma COF, as verified by X-ray photoelectron spectroscopy and H NMR spectroscopy. To the best of our knowledge, this is the first report on the rational design of luminescent COF with predesigned O,N,O'-chelating sites as a fluorescence sensor for highly selective and sensitive metal ion detection. This work may pave the way for designing luminescent COF sensors with functional binding sites for detecting specific metal ions.
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http://dx.doi.org/10.1021/acsami.9b02640DOI Listing
April 2019

Hydrolytically Stable Nanotubular Cationic Metal-Organic Framework for Rapid and Efficient Removal of Toxic Oxo-Anions and Dyes from Water.

Inorg Chem 2019 Feb 5;58(4):2899-2909. Epub 2019 Feb 5.

School of Chemistry and Environment , South China Normal University , Guangzhou , 510006 , PR China.

Cationic framework materials capable of removing anionic pollutants from wastewater are highly desirable but relatively rarely reported. Herein, a cationic MOF (SCNU-Z1-Cl) possessing tubular channels with diameter of 1.5 nm based on Ni(II) and a nitrogen-containing ligand has been synthesized and applied to capture hazardous anionic contaminants from water. The SCNU-Z1-Cl exhibits high BET surface area of 1636 m/g, and shows high hydrolytically stability in pH range from 4 to 10. Owing to the large tubular channels and the uncoordinated anions in the framework, the aqueous-phase anion-exchange applications of SCNU-Z1-Cl were explored with environmentally toxic oxo-anions including CrO, CrO, MnO, and ReO, and organic dyes. The adsorption of oxoanions exhibits high uptake kinetics and the adsorption capacities of CrO, CrO, MnO, and ReO are 126, 241, 292, and 318 mg/g, respectively, which were some of the highest values in the field of MOF/COF. In additional, the selectively is high when other concurrent anions are exist. The anionic dyes with different sizes including methyl orange, acid orange A, congo red, as well as methyl blue can be adsorbed by SCNU-Z1-Cl in few minutes to about 1 h. The adsorption capacities for them are 285, 180, 585, and 262 mg/g, respectively. In contrast, the adsorption kinetics for catinionic dyes with different sizes is obviously lower and exhibit a size-selectively adsorption that only cationic dye with suitable size (rhodamine B) can be adsorbed by SCNU-Z1-Cl. Consequently, SCNU-Z1-Cl can sepearate organic dyes in three different modes: size-dependent, charge-dependent, and kinetics-dependent selective adsorption. The excellent adsorption and separation properties of SCNU-Z1-Cl is attribute to the cationic framework, large tubular channel, as well as the high positive Zeta potential.
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http://dx.doi.org/10.1021/acs.inorgchem.9b00104DOI Listing
February 2019

Assembly of a miRNA-modified QCM sensor for miRNA recognition through response patterns.

J Mol Recognit 2019 05 6;32(5):e2772. Epub 2018 Dec 6.

School of Chemistry and Environment, South China Normal University, Guangzhou, China.

In this paper, a miRNA-based quartz crystal microbalance (QCM) biosensor was fabricated and used to the rapid and effective sensing of miRNA. The specific hybridization between probe miRNA and different selected miRNAs (miR-27a, miR-27b, and Let-7a) cause a different interaction mode, thus display different frequency change and response patterns in the QCM sensor, which were used to detect miR-27a and miR-27b. The selective sensing of miR-27a in mixed miRNA solution was also achieved. This miRNA-based QCM biosensor has the advantages of real-time, label-free, and short cycle detection.
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http://dx.doi.org/10.1002/jmr.2772DOI Listing
May 2019

Construction of a hydrazone-linked chiral covalent organic framework-silica composite as the stationary phase for high performance liquid chromatography.

J Chromatogr A 2017 Oct 5;1519:100-109. Epub 2017 Sep 5.

School of Chemistry and Environment, South China Normal University, Guangzhou, 510006, PR China; Guangdong YanJie Pharmatech Co. Ltd., Guangzhou, 510663, PR China. Electronic address:

Covalent organic frameworks (COFs), as an emerging class of crystalline porous organic polymers, have great potential for applications in chromatographic separation owning to their fascinating crystalline structures and outstanding properties. However, development of COF materials as novel stationary phases in high performance liquid chromatography (HPLC) is just in its infancy. Herein, we report the design and construction of a new hydrazone-linked chiral COF, termed BtaMth COF, from a chiral hydrazide building block (Mth) and present a one-pot synthetic method for the fabrication of [email protected] composite for HPLC separation of isomers. The as-synthesized BtaMth chiral COF displays good crystallinity, high porosity, as well as excellent chemical stability. Meanwhile, the fabricated HPLC column by using [email protected] composite as the new stationary phase exhibits high resolution performances for the separation of positional isomers including nitrotoluene and nitrochlorobenzene, as well as cis-trans isomers including beta-cypermethrin and metconazole. Additionally, some effects such as the composition of the mobile phase and column temperature for HPLC separations on the [email protected] packed column also have been studied in detail. The successful applications indicate the great potentials of hydrazone-linked chiral COF-silica composite as novel stationary phase for the efficient HPLC separation.
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http://dx.doi.org/10.1016/j.chroma.2017.09.007DOI Listing
October 2017

2-Fold Interpenetrating Bifunctional Cd-Metal-Organic Frameworks: Highly Selective Adsorption for CO and Sensitive Luminescent Sensing of Nitro Aromatic 2,4,6-Trinitrophenol.

ACS Appl Mater Interfaces 2017 Feb 26;9(5):4701-4708. Epub 2017 Jan 26.

School of Chemistry and Environment, Guangzhou Key Laboratory of Materials for Energy Conversion and Storage, Guangdong Provincial Engineering Technology Research Center for Materials for Energy Conversion and Storage, South China Normal University , Guanghzou, 510006, P. R. China.

A robust primitive diamond-type topology 3-D metal-organic framework (MOF) of {[Cd(hbhdpy)(bdc)(DMA)]·(HO)} (1, DMA = N,N-dimethylacetamide) was constructed from the planar secondary building units of the dinuclear cadmium clusters, Cd(μ-O), and two linear organic linkers of the new multidentate Schiff base of 4-(2-hydroxy-3-methoxy-benzyli-denehydrazino-carbonyl)-N-pyridin-4-yl-benzamide (Hhbhdpy) through the solvothermal reaction. 1 presents a 2-fold interpenetrating network along with confined narrow channels and rich acylamide groups as well as potential metal open sites for excellent selective CO uptake over CH/N and high luminescent response for 2,4,6-trinitrophenol (TNP) in DMA solution under ambient conditions. With 2-amino-1,4-dicarboxy-benzene (Hbdc-NH) replacing Hbdc, an amine-functionalized MOF of {[Cd(hbhdpy)(bdc-NH) (DMA)]·(HO)} (1-NH) as an isomorphism of 1, was synthesized under the same reaction conditions. Compared with 1, the corresponding bifunctional features of 1-NH is more obvious. To the best of our knowledge, it is the first reported interpenetrating Cd-MOFs with highly sensitive luminescence response for TNP molecules combined with excellent selectivity for CO/N and CO/CH.
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http://dx.doi.org/10.1021/acsami.6b14051DOI Listing
February 2017

Dimension Increase via Hierarchical Hydrogen Bonding from Simple Pincer-like Mononuclear complexes.

Chimia (Aarau) 2015 ;69(11):670-4

MOE Laboratory of Bioinorganic and Synthetic Chemistry State Key Laboratory of Optoelectronic Materials and Technologies Lehn Institute of Functional Materials School of Chemistry and Chemical Engineering Sun Yat-Sen University, Guangzhou 510275, China.

A tetradentate symmetric ligand bearing both coordination and hydrogen bonding sites, N(1),N(3)-bis(1-(1H-benzimidazol-2-yl)-ethylidene)propane-1,3-diamine (H2bbepd) was utilized to synthesize a series of transition metal complexes, namely [Co(H2bbepd)(H(2)O)2]·2ClO(4) (1), [Cu(H2bbepd)(OTs(-))]·OTs(-) (2),[Cu(bbepd)(CH(3)OH)] (3), [Cd(H(2)bbepd)(NO3)2]·CH(3)OH (4), [Cd(H(2)bbepd)(CH(3)OH)Cl]·Cl (5), and [Cd(bbepd)(CH(3)OH)2] (6). These complexes show similar discrete pincer-like coordination units, possessing different arrangements of hydrogen bonding donor and acceptor sites. With or without the aid of uncoordinated anions and solvent molecules, such mononuclear units have been effectively involved in the construction of hierarchical hydrogen bonding assemblies (successively via level I and level II), leading to discrete binuclear ring (complex 2), one-dimensional chain or ribbon (complexes 3, 4 and 6) and two-dimensional layer (complexes 1 and 5) aggregates.
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http://dx.doi.org/10.2533/chimia.2015.670DOI Listing
January 2016

Synthesis of a new cyclosporine-based stationary phase and separation behaviors toward aromatic positional isomers by high-performance liquid chromatography.

J Chromatogr Sci 2015 Apr 18;53(4):548-53. Epub 2014 Jul 18.

School of Chemistry and Environment, South China Normal University, Guangzhou 510006, China Guangzhou Research & Creativity Biotechnology Co. Ltd, Guangzhou Science City 510663, China.

A new cyclosporine-bonded stationary phase has been synthesized through the Staudinger reaction between azido cyclosporine A (CsA) and aminopropyl silica gel and applied in separations of six disubstituted aromatic analytes by high-performance liquid chromatography. For dimethyl phthalate, nitroaniline and chloronitrobenzene, their positional isomers were well-separated on this CsA stationary phase, in which the separation factor for m-/o-dimethyl phthalates was the biggest. For nitrotoluene, dichlorobenzene and benzenediol, the m-/o-isomers were co-eluted. Then, effects of chromatographic conditions (such as types and content of alcoholic modifiers) on separation of nitroaniline positional isomers have been investigated. Retention behaviors of nitroaniline isomers on the column exhibited the strengthening trend along with increasing carbon number of alcohols, from ethanol to 1-propanol, and to 1-butanol. A similar phenomenon was observed by lowering the content of alcohol.
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http://dx.doi.org/10.1093/chromsci/bmu083DOI Listing
April 2015

Effect of chromatographic conditions on enantioseparation of bovine serum albumin chiral stationary phase in HPLC and thermodynamic studies.

Chirality 2013 Sep 2;25(9):487-92. Epub 2013 Aug 2.

Institute of Special Materials/School of Chemistry and Environment, South China Normal University, Guangzhou, China.

Twelve chiral compounds were enantiomerically resolved on bovine serum albumin chiral stationary phase (BSA-CSP) by high-performance liquid chromatography (HPLC) in reversed-phase modes. Chromatographic conditions such as mobile phase pH, the percentage of organic modifier, and concentration of analyte were optimized for separation of enantiomers. For N-(2, 4-dinitrophenyl)-serine (DNP-ser), the retention factors (k) greatly increase from 0.81 to 6.23 as the pH decreasing from 7.21 to 5.14, and the resolution factor (R(s)) exhibited a similar increasing trend (from 0 to 1.34). More interestingly, the retention factors for N-(2, 4-dinitrophenyl)-proline (DNP-pro) decrease along with increasing 1-propanol in mobile phase (3%, 5%, 7% and 9% by volume), whereas the resolution factor shows an upward trend (from 0.96 to 2.04). Moreover, chiral recognition mechanisms for chiral analytes were further investigated through thermodynamic methods.
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http://dx.doi.org/10.1002/chir.22163DOI Listing
September 2013

Preparation and enantioseparation of a new click derived β-cyclodextrin chiral stationary phase.

J Chromatogr Sci 2014 May-Jun;52(5):453-9. Epub 2013 Jun 19.

1Institute of Special Materials & School of Chemistry and Environment, South China Normal University, Guangzhou 510006, China.

A new cyclodextrin-derived chiral stationary phase (denoted as CDA-CSP) was synthesized by immobilizing mono(6(A)-azido-6(A)-deoxy)-per(p-chlorophenyl carbamoylated) β-cyclodextrin derivative to alkynyl modified silica via click chemistry. This newly prepared CSP shows good enantioseparation performance for six chiral compounds (1-6), such as 4-phenyl-oxazolidine-2-thione, two kinds of aryl alcohols, substituted flavonoids and benzoin, in which baseline separation of Analytes 1-4 was achieved under the experimental conditions. The effects of column temperature, mobile phase pH and content of methanol on the enantioseparation characteristics of CDA-CSP were investigated in detail. Retention factor and resolution for Compound 3 gradually reduced with an increase of column temperature, and a good linear relationship was shown between napierian logarithm of selectivity factor and reciprocal of column temperature. In the pH range from 3.56 to 5.50, a change in pH hardly affected the resolution of Analyte 2. In addition, increasing methanol in the mobile phase resulted in rapid eluting of the analytes from the column in reversed-phase mode. The retention factors for Analytes 1 and 3 significantly decreased and their resolution showed different trends.
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http://dx.doi.org/10.1093/chromsci/bmt060DOI Listing
May 2015

Cellulose 2,3-di(p-chlorophenylcarbamate) bonded to silica gel for resolution of enantiomers.

Anal Sci 2013 ;29(6):637-42

School of Chemistry and Environment, South China Normal University, Guangzhou, P. R. China.

In this study, 6-azido-2,3-di(p-chlorophenylcarbamoylated) cellulose was synthesized and bonded onto aminized silica gel to obtain a new chiral stationary phase. Enantioselectivity of the chiral stationary phase and Chiralcel OF suggested promising chiral separation ability of the new cellulose chiral stationary phase. In addition, the effect of trifluoroacetic acid, diethylamine on enantioselectivity and retention factors on the chiral stationary phase in high performance liquid chromatography was investigated. Experimental results revealed that resolution increased as the trifluoroacetic acid concentration increased to 0.3% while resolution declined as the diethylamine concentration increased. Therefore, the optimal concentrations of trifluoroacetic acid and diethylamine were determined to be 0.3 and 0.1%, respectively. In most cases, trifluoroacetic acid shortened the retention of the first eluted enantiomer while it increased the retention of the other. For acidic compounds, with the existence of diethylamine in the mobile phase, the retention of both enantiomers decreased. But for basic compounds, the retention of both enantiomers increased.
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http://dx.doi.org/10.2116/analsci.29.637DOI Listing
October 2013

Tubular metal-organic framework-based capillary gas chromatography column for separation of alkanes and aromatic positional isomers.

J Chromatogr A 2013 Apr 16;1285:132-8. Epub 2013 Feb 16.

Institute of Special Materials & School of Chemistry and Environment, South China Normal University, Guangzhou 510006, China.

In this work, a tubular metal-organic framework, MOF-CJ3, with a large one-dimensional channel was chosen as stationary phase to prepare a capillary gas chromatographic column via a verified dynamic coating procedure. The column offered good separations of linear and branched alkanes, as well as aromatic positional isomers (ethylbenzene, xylene, cresol, hydroquinone, dichlorobenzene, bromobenzonitrile, chloronitrobenzene, and nitrotoluene) based on a combination of host-guest interactions and adsorption effects. Elution sequence of most of the analytes followed an increasing order of their boiling points, except for the separation of n-heptanes/isooctane, cresol, and hydroquinone isomers. Separation behavior of the column upon different organic substances may be related to the tubular pore structure of MOF-CJ3, in which the van der Waals forces between the alkanes and the hydrophobic inner surfaces might have great effect on separation of n-heptanes and isooctane, whereas the separation of cresol and hydroquinone isomers were affected by (OH⋯O) hydrogen bonds formed between the analytes and the 1,3,5-benzenetricarboxylate ligands on the pore wall. The effects of temperature on separation of aromatic positional isomers were investigated to elucidate entropy and enthalpy controlling of the separation process.
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http://dx.doi.org/10.1016/j.chroma.2013.02.024DOI Listing
April 2013

A new biosensor for chiral recognition using goat and rabbit serum albumin self-assembled quartz crystal microbalance.

Chirality 2012 Oct 20;24(10):804-9. Epub 2012 Aug 20.

School of Chemistry and Environment, South China Normal University, Guangzhou, People's Republic of China.

Quartz crystal microbalance (QCM) biosensor was used for the chiral recognition of five pairs of enantiomers by using goat serum albumin (GSA) and rabbit serum albumin (RbSA) as chiral selectors. Serum albumin (SA) was immobilized on the QCM through the self-assembled monolayer technique, and the surface concentration of GSA and RbSA were 8.8 × 10(-12)   mol cm(-2) and 1.2 × 10(-11) mol cm(-2) , respectively. The QCM biosensors showed excellent sensitivity and selectivity. Meanwhile, the chiral recognition of SA sensors was quite species dependent. There were differences between GSA and RbSA sensors in the ability and the preference of chiral recognition. To R,S-1,2,3,4-tetrahydro-1-naphthylamine (R,S-1-TNA), R,S-1-(4-methoxyphenyl)ethylamine (R,S-4-MPEA), and R,S-1-(3-methoxyphenyl)ethylamine (R,S-3-MPEA), the preference of the stereoselective SA-drug binding of the two kinds of SA sensors were consistent. However, to R,S-2-octanol (R, S-2-OT) and R,S-methyl lactate (R,S-MEL), the two kinds of SA sensors had opposite chiral recognition preference. Moreover, the interactions of SA and the five pairs of enantiomers have been further investigated through ultraviolet (UV) and fluorescent (FL) spectra. The UV/FL results were in accordance with the consequence of QCM.
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http://dx.doi.org/10.1002/chir.22074DOI Listing
October 2012

A new two-dimensional cadmium coordination polymer with 1H-imidazole-4-carboxylate and oxalate.

Acta Crystallogr C 2012 Jul 13;68(Pt 7):m177-80. Epub 2012 Jun 13.

School of Chemistry and Environment, South China Normal University, Guangzhou 510006, People's Republic of China.

The title compound, poly[aqua(μ(2)-1H-imidazole-4-carboxylato-κ(3)N(3),O:O')hemi(μ(2)-oxalato-κ(4)O(1),O(2):O(1'),O(2'))cadmium(II)], [Cd(C(4)H(3)N(2)O(2))(C(2)O(4))(0.5)(H(2)O)](n), exhibits a two-dimensional network. The Cd(II) cation is coordinated to one N atom and two carboxylate O atoms from two 1H-imidazole-4-carboxylate (Himc) ligands, two carboxylate O atoms from the bridging oxalate anion and one ligated water molecule; these six donor atoms form a distorted octahedral configuration. The oxalate anion lies on a centre of inversion. The Himc ligands connect the Cd(II) cations to form -Cd-Himc-Cd-Himc-Cd- zigzag chains, with a Cd···Cd separation of 5.8206 (6) Å along the b direction, which are further linked by tetradentate oxalate anions to generate a two-dimensional herringbone architecture in the ab plane. These layers are extended to form a three-dimensional supramolecular framework via O-H···O and N-H···O hydrogen bonds and π-π stacking interactions. The solid-state photoluminscent behaviour of the title compound has been investigated at room temperature.
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http://dx.doi.org/10.1107/S0108270112023153DOI Listing
July 2012

Poly[aqua(μ(3)-5-aza-niumylisophthalato)-(μ-oxalato)neodymium(III)].

Acta Crystallogr Sect E Struct Rep Online 2012 May 4;68(Pt 5):m537. Epub 2012 Apr 4.

School of Chemistry and Environment, South China Normal University, Guangzhou 510006, People's Republic of China.

The title compound, [Nd(C(8)H(6)NO(4))(C(2)O(4))(H(2)O)](n), is a layer-like coordination polymer. The Nd(III) ion is coordinated by four carboxyl-ate O atoms from three bridging 5-aza-nium-yl-isophthalate (Haip) ligands, four carboxyl-ate O atoms from two oxalate (ox) anions and one ligated water mol-ecule in a tricapped trigonal-prismatic geometry. The Haip anion acts as a μ(3)-bridge, connecting three Nd(III) ions through two carboxyl-ate groups; the ox anion adopts a bis-bidentate-bridging mode, linking two Nd(III) ions. The layer framework is further extended to a three-dimensional supra-molecular structure through N-H⋯O and O-H⋯O hydrogen bonds.
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http://dx.doi.org/10.1107/S1600536812013554DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3344297PMC
May 2012

Preparation and chiral separation of a novel immobilized cellulose-based chiral stationary phase in high-performance liquid chromatography.

J Chromatogr Sci 2012 Jul 20;50(6):516-22. Epub 2012 Apr 20.

School of Chemistry and Environment, South China Normal University, Guangzhou, 510006, China.

The chiral selector 6-azido-2, 3-di(p-chlorophenylcarbamoylated) cellulose was synthesized and further chemically immobilized onto 5-μm amino functionalized spherical porous silica gel. It was used as chiral stationary phase in high-performance liquid chromatography. Thirty racemates were successfully separated into enantiomers in either normal phase mode or reversed-phase mode. Good reproducibility and stability of the chiral stationary phase have been demonstrated.
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http://dx.doi.org/10.1093/chromsci/bms047DOI Listing
July 2012

Two mononuclear octahedral complexes with benzimidazole-2-carboxylate: supramolecular networks constructed by hydrogen bonds.

Acta Crystallogr C 2011 Nov 25;67(Pt 11):m346-50. Epub 2011 Oct 25.

School of Chemistry and Environment, South China Normal University, Guangzhou 510006, People's Republic of China.

The title compounds, trans-bis(1H-benzimidazole-2-carboxylato-κ(2)N(3),O)bis(ethanol-κO)cadmium(II), [Cd(C(8)H(5)N(2)O(2))(2)(C(2)H(6)O)(2)], (I), and trans-bis(1H-benzimidazole-κN(3))bis(1H-benzimidazole-2-carboxylato-κ(2)N(3),O)nickel(II), [Ni(C(8)H(5)N(2)O(2))(2)(C(7)H(6)N(2))(2)], (II), are hydrogen-bonded supramolecular complexes. In (I), the Cd(II) ion is six-coordinated by two O atoms from two ethanol molecules, and by two O and two N atoms from two bidentate benzimidazole-2-carboxylate (HBIC) ligands, giving a distorted octahedral geometry. The combination of O-H···O and N-H···O hydrogen bonds results in two-dimensional layers parallel to the ab plane. In (II), the six-coordinated Ni(II) atom, which lies on an inversion centre, shows a similar distorted octahedral geometry to the Cd(II) ion in (I); two benzimidazole molecules occupy the axial sites and the equatorial plane contains two chelating HBIC ligands. Pairs of N-H···O hydrogen bonds between pairs of HBIC anions connect adjacent Ni(II) coordination units to form a one-dimensional chain parallel to the a axis. Moreover, these one-dimensional chains are further linked via N-H···O hydrogen bonds between HBIC anions and benzimidazole molecules to generate a three-dimensional supramolecular framework. The two compounds show quite different supramolecular networks, which may be explained by the fact that different co-ligands occupy the axial sites in the coordination units.
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http://dx.doi.org/10.1107/S0108270111041837DOI Listing
November 2011

The impact of silica gel pore and particle sizes on HPLC column efficiency and resolution for an immobilized, cyclodextrin-based, chiral stationary phase.

J Sep Sci 2010 Sep;33(17-18):2582-9

School of Chemistry and Environment, South China Normal University, Guangzhou, P. R. China.

In this study, the CD derivative, mono (6(A)-azido-6(A)-deoxy)-per(p-chlorophenylcarbamonylated) β-CD was chemically immobilized onto the surface of an amino-functionalized silica gel with different pore (100, 300, and 500Å) and particle (3, 5, and 10 μm) sizes to obtain novel chiral stationary phases. The impact of pore and particle size on the amount of immobilized Ph-β-CD, column performance, and enantioselectivity was investigated by evaluating the separation of a variety of racemates in both the normal- and the reversed-phase modes. Experimental results revealed that the retention factor and resolution of racemates generally decreased with increasing pore size; the column prepared with the smallest (3 μm) silica gel particle size gave the best column performance and enantioselectivity in both the normal- and the reversed-phase modes.
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http://dx.doi.org/10.1002/jssc.200900831DOI Listing
September 2010

Self-assembly of triple helical and meso-helical cylindrical arrays tunable by bis-tripodal coordination converters.

Inorg Chem 2008 Nov 16;47(22):10692-9. Epub 2008 Oct 16.

MOE Laboratory of Bioinorganic and Synthetic Chemistry, State Key Laboratory of Optoelectronic Materials and Technologies, School of Chemistry and Chemical Engineering, Sun Yat-Sen University, Guangzhou 510275, China.

The synergistic interplay of coordination and hydrogen-bonding interactions leads to assembly of isomorphous compounds of the general formula [Ln(ntb) 2](ClO 4) 3.(BDA4BPy) 3.2MeCN} infinity (Ln = La, Sm and Pr, ntb = tris(2-benzimidazoylmethyl)amine, and BDA4BPy = N (1), N (4)-bis(pyridin-4-ylmethylene)-benzene-1,4-diamine), of which polymorphic crystals can be isolated in a different solvent system. In acetonitrile (MeCN) solution, the compounds crystallize as a red color (Ln = La, meso -1, Ln = Pr, meso -2), while in an acetonitrile-benzonitrile (MeCN-PhCN) mixture, yellow crystals are obtained (Ln = Pr, helical - 2). The single-crystal X-ray diffraction analyses of these crystals reveal that the structures display similar cylindrical arrays containing polycompartmental cavities for guest inclusion. Occurrence of polymorphism is due to formation of helical and meso-helical arrays, giving rise to a way to tune the helicity through the solvent effects on the helix propensity of the bis-tripodal coordination converters.
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http://dx.doi.org/10.1021/ic801516bDOI Listing
November 2008

Assembly of CdI2-type coordination networks from triangular ligand and octahedral metal center: topological analysis and potential framework porosity.

Chem Commun (Camb) 2008 Jan(3):356-8

MOE Laboratory of Bioinorganic and Synthetic Chemistry, State Key Laboratory of Optoelectronic Materials and Technologies, School of Chemistry and Chemical Engineering, Sun Yat-Sen University, Guangzhou, 510275, China.

Reaction of a rigid triangular ligand 2,4,6-tris[4-(1H-imidazole-1-yl)phenyl]-1,3,5-triazine (TIPT) with Cd2+ ions affordedrare non-interpenetrating CdI2-type networks which display high thermostability and potential porosity; the topological character of the CdI2-type networks have been analyzed in comparison with three common uniform (4,4), (6,3) and (3,6) plane nets.
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http://dx.doi.org/10.1039/b711457eDOI Listing
January 2008

Zero to three dimensional increase of silver(I) coordination assemblies controlled by deprotonation of 1,3,5-tri(2-benzimidazolyl)benzene and aggregation of multinuclear building units.

Inorg Chem 2007 May 28;46(11):4617-25. Epub 2007 Apr 28.

MOE Laboratory of Bioinorganic and Synthetic Chemistry, State Key Laboratory of Optoelectronic Materials and Technologies, School of Chemistry and Chemical Engineering, Sun Yat-Sen University, Guangzhou 510275, China.

Four Ag(I) complexes of a triangular multidentate ligand 1,3,5-tri(2-benzimidazolyl)benzene (H3TBimB), namely, [Ag2(H3TBimB)2](CF3SO3)2 (1), [Ag4(HTBimB)2]n (2), [Ag9(HTBimB)4(TAZ)]n (HTAZ=1,2,4-triazole) (3), and [Ag17(TBimB)5(HTBimB)(H2O)5]n.nH2O (4), have been synthesized at different pH values adjusted by addition of NH3.H2O under solvothermal conditions and characterized by X-ray single-crystal diffraction. Complex 1 shows an M2L2 dimeric structure, 2 displays a one-dimensional chain containing M4L2 basic units, 3 is a two-dimensional network built up from an M9L4 subunit, and 4 exhibits a three-dimensional framework generated by an M17L6 motif. Dimensional increase in complexes 1-4 was caused by deprotonation of the H3TBimB ligand, thus offering more coordinating donors and resulting in aggregation of oligomeric Ag(I) building units. In the cases of complexes 3 and 4, TAZ or H2O molecules serve as auxiliary ligands to complete the coordination geometry of the Ag(I) ions wherever necessary. The photoluminescent properties of the ligand H3TBimB and the complexes 1-3 have been investigated.
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http://dx.doi.org/10.1021/ic070309kDOI Listing
May 2007

Assembly of trigonal and tetragonal prismatic cages from octahedral metal ions and a flexible molecular clip.

Inorg Chem 2007 Jul 26;46(15):5814-6. Epub 2007 Jan 26.

MOE Laboratory of Bioinorganic and Synthetic Chemistry, State Key Laboratory of Optoelectronic Materials and Technologies, School of Chemistry and Chemical Engineering, Sun Yat-Sen University, Guangzhou 510275, China.

Reaction of a semirigid ligand with two octahedral metal ions with restricted coordination symmetry afforded metalated container complexes showing trigonal or tetragonal outer shapes and inner cavities.
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http://dx.doi.org/10.1021/ic062270+DOI Listing
July 2007

2,2'-(iminodimethylene)bis(1H-benzimidazolium)1+ chloride.

Acta Crystallogr C 2005 Nov 22;61(Pt 11):o642-4. Epub 2005 Oct 22.

School of Chemistry and Chemical Engineering, Sun Yat-Sen University, Guangzhou 510275, People's Republic of China.

The title compound, C(16)H(16)N(5)(+).Cl(-) (nbbH(+).Cl(-)), displays N-H...N, N-H...Cl and pi-pi interactions in the crystal packing. The Cl(-) anion is chelated by the nbbH(+) cation via two N-H...Cl hydrogen bonds. Inter-ion N-H...N and N-H...Cl hydrogen bonds link ions related by 2(1) screw axes into chains along the c axis. These chains are further linked by glide-plane operations to generate a three-dimensional network, which is additionally stabilized by interchain pi-pi interactions.
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http://dx.doi.org/10.1107/S0108270105021992DOI Listing
November 2005