Inclusion compound of retinoic acid with (-cyclodextrin was prepared by coprecipitating method, the structure of resulting product was studied by elemental analysis, differential scanning caloriemetry(DSC) analysis, F...Inclusion compound of retinoic acid with (-cyclodextrin was prepared by coprecipitating method, the structure of resulting product was studied by elemental analysis, differential scanning caloriemetry(DSC) analysis, FT-IR spectroscopy and X-ray diffractometry, and the formed supramolecule self-assembles in aqueous solution according to molar ratio 2:1 of host-guest.展开更多
A supramolecular inclusion complex between β-cyclodextrin（β-CD） and α-naphthylacetic acid was prepared, and its crystal structure was investigated by single-crystal X-ray crystallography. The complex contains two...A supramolecular inclusion complex between β-cyclodextrin（β-CD） and α-naphthylacetic acid was prepared, and its crystal structure was investigated by single-crystal X-ray crystallography. The complex contains two β-CD molecules, one α-naphthylacetic acid, two ethanols and twenty-eight water molecules in the asymmetric unit, which could be formulated as [（C42H70O35）2·（C12H10O2）·（C2H5OH）2·28H2O]. Two β-CD molecules constitute a dimer by face-to-face contact of their secondary hydroxyl sides. At the interface of the dimer, one α-naphthylacetic acid molecule is sandwiched between two β-CD molecules. Each β-CD unit of the dimer includes one ethanol molecule in its cavity. The β-CD dimers are linked together via hydrogen bonding to form layers that are stacked in a brickwork-like pattern. The comparative study of some sandwich complexes elucidates that the interface of the β-CD dimer has a stronger inclusion capacity than the cavity of β-CD for some suitable planar guest molecules. The novel inclusion structure results from the competitive inclusion of α-naphthylacetic acid and ethanol.展开更多
The intramolecular charge transfer dual fluorescence of p-dibutylaminobenzoic acid-b-cyclodextrin inclusion complex showed a substantially higher sensitivity toward aqueous solution pH variation when compared with tha...The intramolecular charge transfer dual fluorescence of p-dibutylaminobenzoic acid-b-cyclodextrin inclusion complex showed a substantially higher sensitivity toward aqueous solution pH variation when compared with that of p-dibutylaminobenzoic acid alone, which established a new principle for direct CT fluorescence sensing in aqueous solution by using the CT fluorophore-cyclodextrin inclusion complex.展开更多
The objective of this paper is to prepare vinpocetine(VIN)inclusion complex and evaluate its brain targeting effect after intranasal administration.In the present study,VIN inclusion complex was prepared in order to i...The objective of this paper is to prepare vinpocetine(VIN)inclusion complex and evaluate its brain targeting effect after intranasal administration.In the present study,VIN inclusion complex was prepared in order to increase its solubility.Stability constant(Kc)was used for host selection.Factors influencing properties of the inclusion complex was investigated.Formation of the inclusion complex was identified by solubility study and DSC analysis.The brain targeting effect of the complex after intranasal administration was studied in rats.It was demonstrated that properties of the inclusion complex was mainly influenced by cyclodextrin type,organic acids type,system pH and host/guest molar ratio.Multiple component complexes can be formed by the addition of citric acid,with solubility improved for more than 23 times.Furthermore,In vivo study revealed that after intranasal administration,the absolute bioavailability of vinpocetine inclusion complex was 88%.Compared with intravenous injection,significant brain targeting effect was achieved after intranasal delivery,with brain targeting index 1.67.In conclusion,by intranasal administration of VIN inclusion complex,a fast onset of action and good brain targeting effect can be achieved.Intranasal route is a promising approach for the treatment of CNS diseases.展开更多
Gallic acid(GA)is a kind of natural polyphenolic compound,but its low aqueous solubility restricts its application in the fields of food and medicine.Cyclodextrin can form inclusion complexes with guest molecules(e.g....Gallic acid(GA)is a kind of natural polyphenolic compound,but its low aqueous solubility restricts its application in the fields of food and medicine.Cyclodextrin can form inclusion complexes with guest molecules(e.g.,essential oils,food supplements)through cavities with special properties to improve aqueous solubility,thermal stability,and bioavailability of guest molecules.In this research,gallic acid/2-hydroxypropyl-β-cyclodextrin inclusion complexes(GA/2-HP-β-CD/ICs)were formed in a highly concentrated solution of 2-HP-β-CD.Bead-free and uniform nanofibrous webs(GA/2-HP-β-CD/IC-NWs)were produced successfully by electrospun GA/HP-β-CD/IC aqueous solution.The initial molar ratio(GA:2-HP-β-CD=1:1)of GA/2-HP-β-CD/IC in the solutions was largely maintained in GA/2-HP-β-CD/IC-NW.The aqueous solubility of GA was enhanced and GA/2-HP-β-CD/IC-NW has displayed fast dissolution property.Furthermore,in comparison with GA powder,GA/2-HP-β-CD/IC-NW demonstrated improved antioxidant capacity.The results suggested that GA/2-HP-β-CD/IC-NW have broad application prospects as orally fast dissolution systems for food supplements.展开更多
The inclusion complex of β-cyclodextrin with m-nitrophenoxyacetic acid was studied by single crystal X-ray diffraction,2D NMR spectroscopy and semi-empirical methods AMI.The crystallographic study shows that two β-c...The inclusion complex of β-cyclodextrin with m-nitrophenoxyacetic acid was studied by single crystal X-ray diffraction,2D NMR spectroscopy and semi-empirical methods AMI.The crystallographic study shows that two β-cyclodextrins are held together by hydrogen bonds to form head-to-head dimers.The disordered guest molecule adjusts itself to attain the most stable accommodation into the cavity in which the nitro group is located at the dimer interface while the carboxyl group is buried in the primary hydroxyl groups of β-cyclodextrin.The guest inside the cavity is disordered over two sites and exhibits mobility.Moreover,2D NMR spectroscopy and theoretical study show the same inclusion behavior.In comparison to the inclusion complex of β-cyclodextrin with p-nitrophenoxyacetic acid,the host-guest stoichiometries are different,i.e.,2：1 for m-nitrophenoxyacetic acid and 1：1 for p-nitrophenoxyacetic acid,while the inclusion orientation and the packing pattern of the host are similar in both complexes.展开更多
Inclusion complexes between β-cyclodextrin （β-CD） and a series of dicarboxylic acids （DAn, n=11-15） were prepared by co-grinding and co-precipitation methods and the [3]pseudorotaxane structure of them was eluci...Inclusion complexes between β-cyclodextrin （β-CD） and a series of dicarboxylic acids （DAn, n=11-15） were prepared by co-grinding and co-precipitation methods and the [3]pseudorotaxane structure of them was elucidated by FTIR, DTA and XRD characterizations. Inclusion complexes of β-CD and α,ω-alkanedicarboxylate anions （DAn^2-） were acquired by neutralizing β-CD/DAn different inclusion complexes with sodium hydroxide and the structure was also proved to be a pseudorotaxane structure by ^1H-NMR spectra and NOESY spectrum. Both the inclusion complexes of β-CD/DAn and β-CD/DAn^2- adopt the [3]pseudorotaxane structure with β-CD arranged in dimers threaded onto one aliphatic chain and the binding mode of 1：1 inclusion complex was excluded based on the consideration of chain conformations.展开更多
2-acetoxy-benzencarboxylic acid is one of the most famous salicylate drugs today, a pharmaceutically active compound known as aspirin. It is poorly soluble in water which results in decreased bioavailability of the dr...2-acetoxy-benzencarboxylic acid is one of the most famous salicylate drugs today, a pharmaceutically active compound known as aspirin. It is poorly soluble in water which results in decreased bioavailability of the drug in the organism. The increase in water solubility of insoluble or poorly soluble drugs is therefore of great importance, which is the aim of this study. Inclusion of the drug in the molecule with a higher water solubility significantly increases its solubility and biological availability. Natural and hydrophilic derivatives of natural cyclodextrins are in the spotlight for their role as solubilizing excipients. Studies indicate that the use of β-cyclodextrin inclusion complexes with acetylsalicylic acid formed, increases the solubility of the drug in water. Many advantages of drug-complexation with cyclodextrins have been reported in scientific literature which includes increased solubility, enhanced bioavailability, improved stability, masking of bad test or odour, reduced side effect. Orally administered aspirin requires high and frequent dosing because it undergoes extensive pre systematic metabolism. Also chronic oral aspirin use is associated with serious gastrointestinal side-effects. Complexation with CD alleviates the side effects to some extent. The bioavailability and solubility of aspirin has to be increased to overcome the side-effects of aspirin related to stomach and gastro intestinal tract. The phase solubility study was performed according to the method of Higuchi and Connors by adding the 2-acetoxi-benzencarboxylic acid in excess to different concentrations of different beta cyclodextrins solutions. Phase solubility study records shown that the stability constant and complex stoichiometry of 2-acetoxi-benzencarboxylic acid-CD complexes gives linearly improve with the concentration of CD. Complexes were analyzed by UV-VIS spectroscopy and were characterized by infrared spectroscopy.展开更多
Inclusion complex of ferrocene(Fc) with β-cyclodextrin(β-CD) has been synthesized in ethylene glycol. It was unsolvable in water and had been successfully used in the preparation of β-CD-Fc inclusion complex modifi...Inclusion complex of ferrocene(Fc) with β-cyclodextrin(β-CD) has been synthesized in ethylene glycol. It was unsolvable in water and had been successfully used in the preparation of β-CD-Fc inclusion complex modified carbon paste electrode (CFCPE). Using the inclusion complex as the electroactive substance greatly increased the stability and reproducibility of CFCPE than using Fc.展开更多
文摘Inclusion compound of retinoic acid with (-cyclodextrin was prepared by coprecipitating method, the structure of resulting product was studied by elemental analysis, differential scanning caloriemetry(DSC) analysis, FT-IR spectroscopy and X-ray diffractometry, and the formed supramolecule self-assembles in aqueous solution according to molar ratio 2:1 of host-guest.
基金Supported by the Natural Science Foundation of Hainan Province, China(No.808145)the Doctoral Foundation of Hainan Normal University, China(No.103303)the Key Discipline of Hainan Province Organic Chemistry, China(No.006).
文摘A supramolecular inclusion complex between β-cyclodextrin（β-CD） and α-naphthylacetic acid was prepared, and its crystal structure was investigated by single-crystal X-ray crystallography. The complex contains two β-CD molecules, one α-naphthylacetic acid, two ethanols and twenty-eight water molecules in the asymmetric unit, which could be formulated as [（C42H70O35）2·（C12H10O2）·（C2H5OH）2·28H2O]. Two β-CD molecules constitute a dimer by face-to-face contact of their secondary hydroxyl sides. At the interface of the dimer, one α-naphthylacetic acid molecule is sandwiched between two β-CD molecules. Each β-CD unit of the dimer includes one ethanol molecule in its cavity. The β-CD dimers are linked together via hydrogen bonding to form layers that are stacked in a brickwork-like pattern. The comparative study of some sandwich complexes elucidates that the interface of the β-CD dimer has a stronger inclusion capacity than the cavity of β-CD for some suitable planar guest molecules. The novel inclusion structure results from the competitive inclusion of α-naphthylacetic acid and ethanol.
基金This work was support by NNSF of China through grants No.29975023 and No.20175020.
文摘The intramolecular charge transfer dual fluorescence of p-dibutylaminobenzoic acid-b-cyclodextrin inclusion complex showed a substantially higher sensitivity toward aqueous solution pH variation when compared with that of p-dibutylaminobenzoic acid alone, which established a new principle for direct CT fluorescence sensing in aqueous solution by using the CT fluorophore-cyclodextrin inclusion complex.
文摘The objective of this paper is to prepare vinpocetine(VIN)inclusion complex and evaluate its brain targeting effect after intranasal administration.In the present study,VIN inclusion complex was prepared in order to increase its solubility.Stability constant(Kc)was used for host selection.Factors influencing properties of the inclusion complex was investigated.Formation of the inclusion complex was identified by solubility study and DSC analysis.The brain targeting effect of the complex after intranasal administration was studied in rats.It was demonstrated that properties of the inclusion complex was mainly influenced by cyclodextrin type,organic acids type,system pH and host/guest molar ratio.Multiple component complexes can be formed by the addition of citric acid,with solubility improved for more than 23 times.Furthermore,In vivo study revealed that after intranasal administration,the absolute bioavailability of vinpocetine inclusion complex was 88%.Compared with intravenous injection,significant brain targeting effect was achieved after intranasal delivery,with brain targeting index 1.67.In conclusion,by intranasal administration of VIN inclusion complex,a fast onset of action and good brain targeting effect can be achieved.Intranasal route is a promising approach for the treatment of CNS diseases.
基金This work was supported by the Project of the Jilin Province Development and Reform Commission,China(No.2020C023-5)the National Natural Science Foundation of China(No.31772058).
文摘Gallic acid(GA)is a kind of natural polyphenolic compound,but its low aqueous solubility restricts its application in the fields of food and medicine.Cyclodextrin can form inclusion complexes with guest molecules(e.g.,essential oils,food supplements)through cavities with special properties to improve aqueous solubility,thermal stability,and bioavailability of guest molecules.In this research,gallic acid/2-hydroxypropyl-β-cyclodextrin inclusion complexes(GA/2-HP-β-CD/ICs)were formed in a highly concentrated solution of 2-HP-β-CD.Bead-free and uniform nanofibrous webs(GA/2-HP-β-CD/IC-NWs)were produced successfully by electrospun GA/HP-β-CD/IC aqueous solution.The initial molar ratio(GA:2-HP-β-CD=1:1)of GA/2-HP-β-CD/IC in the solutions was largely maintained in GA/2-HP-β-CD/IC-NW.The aqueous solubility of GA was enhanced and GA/2-HP-β-CD/IC-NW has displayed fast dissolution property.Furthermore,in comparison with GA powder,GA/2-HP-β-CD/IC-NW demonstrated improved antioxidant capacity.The results suggested that GA/2-HP-β-CD/IC-NW have broad application prospects as orally fast dissolution systems for food supplements.
文摘The inclusion complex of β-cyclodextrin with m-nitrophenoxyacetic acid was studied by single crystal X-ray diffraction,2D NMR spectroscopy and semi-empirical methods AMI.The crystallographic study shows that two β-cyclodextrins are held together by hydrogen bonds to form head-to-head dimers.The disordered guest molecule adjusts itself to attain the most stable accommodation into the cavity in which the nitro group is located at the dimer interface while the carboxyl group is buried in the primary hydroxyl groups of β-cyclodextrin.The guest inside the cavity is disordered over two sites and exhibits mobility.Moreover,2D NMR spectroscopy and theoretical study show the same inclusion behavior.In comparison to the inclusion complex of β-cyclodextrin with p-nitrophenoxyacetic acid,the host-guest stoichiometries are different,i.e.,2：1 for m-nitrophenoxyacetic acid and 1：1 for p-nitrophenoxyacetic acid,while the inclusion orientation and the packing pattern of the host are similar in both complexes.
文摘Inclusion complexes between β-cyclodextrin （β-CD） and a series of dicarboxylic acids （DAn, n=11-15） were prepared by co-grinding and co-precipitation methods and the [3]pseudorotaxane structure of them was elucidated by FTIR, DTA and XRD characterizations. Inclusion complexes of β-CD and α,ω-alkanedicarboxylate anions （DAn^2-） were acquired by neutralizing β-CD/DAn different inclusion complexes with sodium hydroxide and the structure was also proved to be a pseudorotaxane structure by ^1H-NMR spectra and NOESY spectrum. Both the inclusion complexes of β-CD/DAn and β-CD/DAn^2- adopt the [3]pseudorotaxane structure with β-CD arranged in dimers threaded onto one aliphatic chain and the binding mode of 1：1 inclusion complex was excluded based on the consideration of chain conformations.
文摘2-acetoxy-benzencarboxylic acid is one of the most famous salicylate drugs today, a pharmaceutically active compound known as aspirin. It is poorly soluble in water which results in decreased bioavailability of the drug in the organism. The increase in water solubility of insoluble or poorly soluble drugs is therefore of great importance, which is the aim of this study. Inclusion of the drug in the molecule with a higher water solubility significantly increases its solubility and biological availability. Natural and hydrophilic derivatives of natural cyclodextrins are in the spotlight for their role as solubilizing excipients. Studies indicate that the use of β-cyclodextrin inclusion complexes with acetylsalicylic acid formed, increases the solubility of the drug in water. Many advantages of drug-complexation with cyclodextrins have been reported in scientific literature which includes increased solubility, enhanced bioavailability, improved stability, masking of bad test or odour, reduced side effect. Orally administered aspirin requires high and frequent dosing because it undergoes extensive pre systematic metabolism. Also chronic oral aspirin use is associated with serious gastrointestinal side-effects. Complexation with CD alleviates the side effects to some extent. The bioavailability and solubility of aspirin has to be increased to overcome the side-effects of aspirin related to stomach and gastro intestinal tract. The phase solubility study was performed according to the method of Higuchi and Connors by adding the 2-acetoxi-benzencarboxylic acid in excess to different concentrations of different beta cyclodextrins solutions. Phase solubility study records shown that the stability constant and complex stoichiometry of 2-acetoxi-benzencarboxylic acid-CD complexes gives linearly improve with the concentration of CD. Complexes were analyzed by UV-VIS spectroscopy and were characterized by infrared spectroscopy.
文摘Inclusion complex of ferrocene(Fc) with β-cyclodextrin(β-CD) has been synthesized in ethylene glycol. It was unsolvable in water and had been successfully used in the preparation of β-CD-Fc inclusion complex modified carbon paste electrode (CFCPE). Using the inclusion complex as the electroactive substance greatly increased the stability and reproducibility of CFCPE than using Fc.
