Ai-Di Qi

Publications (11)27.06 Total impact

• Article: Thionyl Chloride-Catalyzed Preparation of Microporous Organic Polymers through Aldol Condensation

  Yan-Chao Zhao, Ding Zhou, Qi Chen, Xin-Jian Zhang, Ning Bian, Ai-Di Qi, Bao-Hang Han
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  ABSTRACT: We demonstrated the synthesis of five kinds of microporous organic polymers based on aldol self-condensation of di- and multiacetyl-containing building blocks catalyzed by thionyl chloride. The α,β-unsaturated ketone (dimerization) and 1,3,5-trisubstituted benzene (cyclotrimerization) can be observed in the resulting polymers by Fourier transform infrared and solid-state 13C CP/MAS NMR spectroscopy. The regular spheres and nanometer-scaled cavities were also seen from scanning electron microscopy and high-resolution transmission electron microscopy images. The highest Brunauer–Emmet–Teller specific surface area up to 832 m2 g–1 was obtained for the resulting polymers with a pore volume of 0.48 cm3 g–1. The polymers show great hydrogen storage capacities (up to 1.56 wt %) at 77 K and 1 bar. These excellent characteristics would make them become promising candidates for heterogeneous catalysis, separation, and gas storage.
  07/2011;
• Article: [Simultaneous determination of fumonisins B1 and B2 in traditional Chinese medicines by high-performance liquid chromatography-tandem mass spectrometry].

  Ting-Ting Xie, Feng Qiu, Mei-Hua Yang, Ai-Di Qi
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  ABSTRACT: A rapid and sensitive analytical method was developed for the simultaneous determination of fumonisins B1 and B2 in traditional Chinese medicines by HPLC-MS/MS. The detection limits for fumonisins B1 and B2 were 0.25 ng x mL(-1) corresponding to 2 microg x kg(-1) in samples. Recoveries from different samples spiked with fumonisins B1 and B2 at levels ranging from 0.2 to 3 mg x kg(-1) were 84.0%-96.1% and 86.3%-99.3%, respectively. Among the total of 34 samples purchased from local markets, ten samples of which were visibly moldy samples due to inappropriate storage, and 24 were normal samples. The results showed that 6 of the visibly moldy samples and 5 of the normal samples were contaminated with total fumonisins at levels ranging 82.4-2349 microg x kg(-1) and 102-729 microg x kg(-1), respectively.
  Yao xue xue bao = Acta pharmaceutica Sinica 07/2011; 46(7):822-7.
• Article: Paraquat detoxification with p-sulfonatocalix-[4]arene by a pharmacokinetic study.

  Gui-Fang Wang, Xiao-Liang Ren, Min Zhao, Xi-Long Qiu, Ai-Di Qi
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  ABSTRACT: The p-sulfonatocalix[n]arenes are supposed to show potential application in the clinical treatment of viologen poisoning. In the present study, p-sulfonatocalix[4]arene (C4AS), the most common derivative of p-sulfonatocalix[n]arenes, is used to study the antidotic mechanism for paraquat (PQ) by pharmacokinetics in vivo. A high-performance liquid chromatography (HPLC) method was established to determine the concentration of PQ in rat plasma. The results showed that the peak plasma concentration (C(max)) and area under the plasma concentration-time curve (AUC(0-t)) were significantly lower after C4AS intervention than in the PQ intoxication group. It was considered that C4AS has great effective detoxication to PQ poisoning, and the results of in vitro intestinal absorption studies showed that C4AS can inhibit the absorption of PQ via oral administration by forming a stable inclusion constant.
  Journal of Agricultural and Food Chemistry 03/2011; 59(8):4294-9. · 2.82 Impact Factor
• Article: Sugar-bearing tetraphenylethylene: novel fluorescent probe for studies of carbohydrate-protein interaction based on aggregation-induced emission.

  Jin-Xiang Wang, Qi Chen, Ning Bian, Fen Yang, Jing Sun, Ai-Di Qi, Chao-Guo Yan, Bao-Hang Han
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  ABSTRACT: Neutral sugar-bearing tetraphenylethenes (TPE) are designed and prepared as "turn-on" luminescent sensors for lectins and glycosidases based on aggregation-induced emission. Through aggregation derived from carbohydrate-lectin binding, multivalent mannosyl-bearing TPE shows a good selectivity and sensitivity to Con A by switching on the fluorescence of water-soluble tetraphenylethylene-based glyco-conjugates in aqueous solution. Meanwhile, cellobiosyl-bearing TPE can be used to investigate enzymatic hydrolysis based on emission enhancing by glycosidase-induced aggregation.
  Organic & Biomolecular Chemistry 02/2011; 9(7):2219-26. · 3.70 Impact Factor
• Article: Kinetics and mechanism of 2,3,5,4'-tetrahydroxystilbene-2-O-β-d-glycoside (THSG) degradation in aqueous solutions.

  Xiao-liang Ren, Gui-fang Wang, Meng Wang, Hui-zi Ou-Yang, Ai-di Qi
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  ABSTRACT: The hydrolytic kinetics and degradation mechanism of 2,3,5,4'-tetrahydroxystilbene-2-O-β-d-glycoside (THSG) extracted from Radix Polygoni Multiflori (a commonly used official Chinese herbal Heshouwu), were investigated using reversed-phase high-performance liquid chromatography (HPLC) and liquid chromatography-mass spectrometry (LC-MS). The influences of pH (1.5-9.9), temperature (25-60°C) and irradiation on the hydrolysis of THSG were studied in aqueous solutions. The results showed that the degradation of THSG was pH-, temperature- and irradiation-dependent and all followed first-order kinetics. The effect of temperature on the rate of THSG degradation was characterized using the Arrhenius equation. Maximum stability of THSG was found at pH 1.5 (t(0.5)=47.57 d). THSG was unstable in alkaline and irradiation conditions. The active energy (E(a)) of THSG degradation in aqueous solution at pH 6.8 (most frequently adopted extract solvent) under lucifugal and irradiation conditions was 47.7kJmol(-1) and 25.3kJmol(-1), respectively. Three hydrolytic products of THSG were identified by LC-MS. Cis-trans isomerism took place under irradiation, and hydrolysis took place in acid-base conditions. Moreover, further oxidation on aglycon occurred after hydrolytic cleavage of phenolic glycoside in acidic conditions. The possible hydrolytic pathways of THSG are proposed.
  Journal of pharmaceutical and biomedical analysis 12/2010; 55(1):211-5. · 2.45 Impact Factor
• Article: Glucosamine hydrochloride functionalized tetraphenylethylene: a novel fluorescent probe for alkaline phosphatase based on the aggregation-induced emission.

  Qi Chen, Ning Bian, Chun Cao, Xi-Long Qiu, Ai-Di Qi, Bao-Hang Han
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  ABSTRACT: Grafting of glucosamine hydrochloride moieties to tetraphenylethylene (TPE) motif furnished a novel cationic water-soluble tetraphenylethylene derivative (GH-TPE). With aggregation-induced emission properties, GH-TPE was used for fluorometric detection to alkaline phosphatase through enzyme-triggered de-aggregation of the ensemble of GH-TPE and substrate.
  Chemical Communications 06/2010; 46(23):4067-9. · 6.17 Impact Factor
• Article: Biomimetic surface modification of poly (L-lactic acid) with gelatin and its effects on articular chondrocytes in vitro.

  Yuan Lu Cui, Xin Hou, Ai Di Qi, Xiang Hui Wang, Hong Wang, Kai Yong Cai, Yu Ji Yin, Kang De Yao
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  ABSTRACT: Our objective in this study was to investigate the efficiency of two treatments for poly (L-lactic acid) (PLLA) surface modification with gelatin, via entrapment and coupling, using 1-ethyl-3-(3-dimethylaminopropyl)carbodiimide (EDC) and N-hydroxysuccinimide (NHS). The properties of original PLLA, gelatin-entrapped, and coupled PLLA films were investigated by water contact angle measurement and electron spectroscopy for chemical analysis (ESCA). The water contact angle indicated that the incorporation of gelatin resulted in a change in hydrophilicity, and the ESCA data suggested that the modified PLLA films became enriched with nitrogen atoms. The cytocompatibility of modified PLLA films might be improved. Therefore, we examined the attachment and proliferation of bovine articular chondrocyte seeded on modified PLLA films and virgin films. A whole-cell enzyme-linked immunosorbent assay (cell ELISA) that detects 5-bromo-2'-deoxyuridine (BrdU) incorporation during DNA synthesis and collagen type II secretion was applied to evaluate the chondrocytes on different PLLA films and tissue culture plates (TCPS). Cell viability was estimated by the MTT [3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide] assay, and cell function was assessed by measuring glycosaminoglycan (GAG) secreted by chondrocytes. These results implied that gelatin used to modify the PLLA surface through entrapment and coupling could enhance chondrocyte adhesion, proliferation, and function.
  Journal of Biomedical Materials Research Part A 10/2003; 66(4):770-8. · 2.63 Impact Factor
• Article: Biomimetic surface modification of poly(L-lactic acid) with chitosan and its effects on articular chondrocytes in vitro.

  Yuan Lu Cui, Ai Di Qi, Wen Guang Liu, Xiang Hui Wang, Hong Wang, Dong Ming Ma, Kang De Yao
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  ABSTRACT: The objective of this study was to investigate the efficiency of two treatments for poly(L-lactic acid) (PLLA) surface modification with chitosan, via entrapment and coupling by using 1-ethyl-3-(3-dimethylaminopropyl)carbodiimide and N-hydroxysuccinimide. The properties of original PLLA films, chitosan-entrapped and coupled PLLA films were investigated by water contact angle measurement and electron spectroscopy for chemical analysis (ESCA). The contact angle indicated the change in hydrophilicity and the ESCA data suggested that the modified PLLA films became enriched with nitrogen atoms. The cytocompatibility of modified PLLA films might be improved. Therefore, the attachment and proliferation of bovine articular chondrocyte seeded on modified PLLA films and control one were examined. A whole cell enzyme-linked immunosorbent assay (Cell ELISA) that detects the BrdU incorporation during DNA synthesis and collagen type II secretion was applied to evaluate the chondrocytes on different PLLA films and tissue culture plates. Cell viability was estimated by the MTT assay and cell function were assessed by measuring sulfated glycosaminoglycan secreted by chondrocytes. These results implied that chitosan used to modify PLLA surface through entrapment and coupling could enhance the chondrocyte adhesion, proliferation and function.
  Biomaterials 10/2003; 24(21):3859-68. · 7.40 Impact Factor
• Source

  Available from: supram.nankai.edu.cn

  Article: Molecular Binding Ability and Selectivity of Natural α-, β-, γ-Cyclodextrins and Oligo(ethylenediamino) Modified β-Cyclodextrins with Chinese Traditional Medicines

  Ai-Di Qi, Li Li, Yu Liu
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  ABSTRACT: The binding ability andinclusion complexation behavior of natural -, -, -cyclodextrins (1–3) and two mono[6-oligo(ethylenediamino)-6-deoxy]--cyclodextrins(4, 5) with fourChinese traditional medicines, that is, -asarone (AS), ferulic acid (FA), magnolol (MA) and honokiol (HO), have been investigated in aqueous phosphate buffer solutions(pH = 7.20). The spectral titrations have been performed at 25 C by using fluorescence spectroscopy to calculate the complex stability constants (KS) and Gibbs free energy changes ( G) for the stoichiometric 1 : 1 inclusion complexation of hosts1–5 with guest medicines. The results obtained indicate that the different guest medicines fit in with hydrophobic cavities of different sizes and the appended substitutes of hosts 4 and 5 change the hydrophobic microenvironment of -cylcodextrin 2, influencing the original binding ability and molecular selectivity of host 2 consequently. The binding ability and inclusion complexation behavior of these hosts 1–5 are discussed according to the size/shape fit concept and hydrogen bonding interaction between host cyclodextrins and guest medicine molecules.
  Journal of Inclusion Phenomena 01/2003; 45(1):69-72. · 1.89 Impact Factor
• Article: Molecular Recognition Study on a Supramolecular System. 10.1 Inclusion Complexation of Modified β-Cyclodextrins with Amino Acids:  Enhanced Enantioselectivity for l/d-Leucine

  Yu Liu, Yi-Min Zhang, Ai-Di Qi, Rong-Ti Chen, Keiko Yamamoto, Takehiko Wada, Yoshihisa Inoue
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  ABSTRACT: The novel β-cyclodextrin (β-CD) derivatives bearing a m-toluidinyl or (9-fluorenyl)alkylamino moiety have been synthesized by a convenient method in 45% and 66% yields, respectively. The stability constants (Ks) and Gibbs free energy changes (−ΔG) for inclusion complexation of mono-[6-(m-toluidinyl)-6-deoxy]-β-cyclodextrin 1 and mono-[6-[(9-fluorenyl)alkylamino]-6-deoxy]-β-cyclodextrin 2 with various l/d-amino acids have been examined by the fluorescence spectrum method in buffered aqueous solution (pH = 7.20) at 20−23 °C. The modified β-cyclodextrins, possessing a toluidinyl or fluorenyl moiety as fluorescent probe, can recognize not only the size and shape but also the chirality of l/d-amino acids, giving fairly good enantioselectivity up to 33 for l/d-leucine. β-Cyclodextrin derivative 1 gave the highest Ks for l-leucine and the lowest for d-leucine among the amino acid series, eventually showing the highest enantioselectivity for l/d-amino acids. The molecular recognition ability and enantioselectivity for amino acids of the modified β-cyclodextrins 1 and 2 are discussed from the viewpoint of the size/shape−fit relationship between the host cavity and the guest molecules.
  03/1997;
• Article: Molecular Recognition Study of a Supramolecular System

  Yu Liu, Bao-Hang Han, Ai-Di Qi, Rong-Ti Chen
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  ABSTRACT: The competitive inclusion method was used to determine the stability constants (logKa) for complexation of natural α-cyclodextrin (1) with aliphatic amino acids in acidic solution. The stability constants (logKa) for the complexation of modified α-cyclodextrin, mono- [6-(1-pyridinio)-6-deoxy]-α-cyclodextrin (2), with these biological molecules were measured using the differential spectra method. Both natural α-cyclodextrin (1) and chemically modified α-cyclodextrin (2) can recognize not only the size of guest amino acid molecules and the length of their hydrophobic side chains, but also the chirality of enantiotopicL/D-amino acids. The longer the hydrophobic side chain borne on an amino acid, the more stable the complex formed by α-cyclodextrin hosts (1) and (2). Host compounds (1) and (2) preferably includeL-amino acids, which would benefit from discrimination ofL/D-amino acids. Introduction of a positively charged 1-pyridinio moiety to C-6 of α-cyclodextrin apparently enlarges the inclusion ability and enantioselectivity by electrostatic interaction. Comparing the data obtained in acidic medium with those formerly measured in pH 7.20 phosphate buffer solution, a result can be given: when the pH of the medium increases, the complexation ability and selectivity of modified α-cyclodextrin (2) for most amino acids examined here are slightly enhanced, showing the highest enantioselectivity up to 10.3 forL/D-serine.
  Bioorganic Chemistry.