An Electrochemical Approach for the Cucurbit[7]uril/Carbendazim Supramolecular Inclusion Complex. Application to Carbendazim Determination in Apples

2010 ◽  
Vol 23 (1) ◽  
pp. 189-195 ◽  
Author(s):  
María del Pozo ◽  
Marina Alonso ◽  
Lucas Hernández ◽  
Carmen Quintana
Author(s):  
Süheyla Özbey ◽  
F. B. Kaynak ◽  
M. Toğrul ◽  
N. Demirel ◽  
H. Hoşgören

AbstractA new type of inclusion complex, S(–)-1 phenyl ethyl ammonium percholorate complex of R-(–)-2-ethyl - N - benzyl - 4, 7, 10, 13 - tetraoxa -1- azacyclopentadecane, has been prepared and studied by NMR, IR and single crystal X-ray diffraction techniques. The compound crystallizes in space group


Author(s):  
Narendar D ◽  
Ettireddy S

The content of this investigation was to study the influence of β-cyclodextrin and hydroxy propyl-β-cyclodextrin complexation on enhancement of solubility and dissolution rate of isradipine. Based on preliminary phase solubility studies, solid complexes prepared by freeze drying method in 1:1 molar ratio were selected and characterized by DSC for confirmation of complex formation. Prepared solid dispersions were evaluated for drug content, solubility and in vitro dissolution. The physical stability of optimized formulation was studied at refrigerated and room temperature for 2 months. Solid state characterization of optimized complex performed by DSC and XRD studies.  Dissolution rate of isradipine was increased compared with pure drug and more with HP-β-CD inclusion complex than β-CD. DSC and XRD analyzes that drug was in amorphous form, when the drug was incorporated as isradipine β-CD and HP-β-CD inclusion complex. Stability studies resulted in low or no variations in the percentage of complexation efficiency suggesting good stability of molecular complexes. The results conclusively demonstrated that the enhancement of solubility and dissolution rate of isradipine by drug-cyclodextrin complexation was achieved.   


Author(s):  
Shabnam Ain ◽  
V Gupta ◽  
Babita K ◽  
Q Ain ◽  
J Dahiya

Aqueous solubility is a critical factor for optimum drug delivery. In the present study, we investigated the potential of drug-cyclodextrin complexation as an approach for improving the solubility and bioavailability of famotidine, an H2-receptor antagonist and acid reducing drug which has poor solubility and bioavailability. Solubility improvement of drug by β-cyclodextrin was done by simple complexation approach using physical, kneading and co-precipitation methods and compared with physical mixture. Phase solubility profile indicated that the solubility of famotidine was significantly increased in presence of β-cyclodextrin and shows a linear graph with β-cyclodextrin indicating formation of inclusion complexes in a 1:1 molar ratio. β-Cyclodextrin-famotidine mixture have maximum stability constant 1477.6 M-1. The inclusion complex ratio 1:1 of kneading mixture was selected based on drug release profile and compared with physical mixture. Further characterization was done by  using Fourier transform infrared spectroscopy (FTIR), differential scanning calorimetry (DSC) and scanning electron microscopy (SEM) to identify the physicochemical interaction between drug and carrier and its effect on dissolution. Dissolution rate studies for selected inclusion complex was performed in 0.1 N HCl (pH 1.2), phosphate buffer (pH 7.5) and distilled water (pH 6.8) and compared these to pure drug profile which was found to be 2.34 fold increase in distilled water, 1.83 fold in HCl and 2.01 fold in phosphate buffer (pH 7.5). These results suggest that the kneaded complex of famotidine with β-cyclodextrin as hydrophilic complexation agent can substantially enhance the solubility and dissolution rate. Such complex has promising potential to improve the bioavailability of famotidine.  


2018 ◽  
Vol 69 (7) ◽  
pp. 1838-1841
Author(s):  
Hajnal Kelemen ◽  
Angella Csillag ◽  
Bela Noszal ◽  
Gabor Orgovan

Ezetimibe, the antihyperlipidemic drug of poor bioavailability was complexed with native and derivatized cyclodextrins.The complexes were characterized in terms stability, stoichiometry and structure using various 1D and 2D solution NMR spectroscopic techniques. The complexes were found to be of moderate stability (logK[3). The least stable inclusion complex is formed with b-cyclodextrin, while the ezetimibe-methylated-b--cyclodextrin has a 7-fold higher stability. The results can be useful to improve the poor water-solubility and the concomitant bioavailability of ezetimibe.


2019 ◽  
Vol 70 (5) ◽  
pp. 1574-1578
Author(s):  
Cristian Neamtu ◽  
Bogdan Tutunaru ◽  
Adriana Samide ◽  
Alexandru Popescu

Electrochlorination constitutes an electrochemical approach for the treatment of pesticide-containing wastewaters. This study evaluated the electrochemical and thermal stability of four pesticides and the efficiency of electrochlorination to remove and detoxify the simulated polluted water with: Acetamiprid, Emamectin, Imidacloprid and Propineb. This study reports the experimental results obtained by cyclic voltammetry and electrolysis at constant current density in association with UV-Vis spectrophotometry. In saline waters this pesticides are electrochemical active and anodic peaks are registered in the corresponding voltammograms. After thermal combustion, in a gaseous nitrogen atmosphere, a residue ranging from 15 to 45 % is observed at 500 �C.


2015 ◽  
Vol 10 (2) ◽  
pp. 114-120 ◽  
Author(s):  
Jiaojiao Ding ◽  
Jinfeng Li ◽  
Shirui Mao

2007 ◽  
Vol 832 (1-3) ◽  
pp. 84-89 ◽  
Author(s):  
Adam Huczyński ◽  
Małgorzata Ratajczak-Sitarz ◽  
Andrzej Katrusiak ◽  
Bogumil Brzezinski

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