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Jurecska L.,Eotvos Lorand University | Dobosy P.,Eotvos Lorand University | Barkacs K.,Eotvos Lorand University | Fenyvesi T.,CycloLab Cyclodextrin Research and Development Laboratory Ltd. | Zaray G.,Eotvos Lorand University
Journal of Pharmaceutical and Biomedical Analysis | Year: 2015

Due to the increasing amount of persistent organic pollutants (POPs) in general and pharmaceutical residues in particular in municipal wastewater, the efficiency of water treatment technologies should be improved. Following the biological treatment of wastewater nanofiltration offers a possible way for the removal of POPs. In this study β-cyclodextrin containing nanofilters having different chemical composition and thickness (1.5-3.5. mm) were investigated. For their characterization, their adsorption capacity was determined applying ibuprofen containing model solution and total organic carbon (TOC) analyzer.It could be established that the regeneration of nanofilters with ethanol and the application of inorganic additives (NaCl, NaHCO3, NH4HCO3) increased the adsorption capacity of nanofilters. The best results were achieved with chemical composition of 30m/m% β-cyclodextrin polymer beads and 70m/m% ultra-high molecular weight polyethylene in the presence of 12mmol ammonium hydrogen carbonate/nanofilter. © 2015 Elsevier B.V.

Csempesz F.,Eotvos Lorand University | Sule A.,Eotvos Lorand University | Puskas I.,CycloLab Cyclodextrin Research and Development Laboratory Ltd.
Colloids and Surfaces A: Physicochemical and Engineering Aspects | Year: 2010

Complexation of active therapeutic agents with cyclodextrins (CDs) offers potential uses in pharmaceutical and biomedical applications for controlling drug delivery and targeting. This paper reports on possible enhancement of the aqueous solubility and bioavailability of sparingly soluble statins (simvastatin and lovastatin) by inclusion complexation with native β-cyclodextrin and a chemically modified β-cyclodextrin, respectively. Complexation-induced surface activity of the supramolecular associates and the effect of the pure CDs and the amphiphilic CD-statin complexes on the physical stability of colloidal liposomes of dipalmitoyl phosphatidyl choline (DPPC) are discussed. It was shown that complexation with either cyclodextrin may lead to considerable improvement of the aqueous solubilities of both statins. Randomly methylated β-cyclodextrin (RAMEB) showed particularly outstanding solubilizing effects. The cyclodextrin molecules dissolved in the medium of liposome dispersions strongly reduced the physical stability of the phospholipid membranes. Complexation of the hydrophobic DPPC chains with cyclodextrins may ultimately lead to disintegration of the vesicles. In ternary systems, where due to the complexation of the pharmacon with the cyclodextrin amphiphilic CD-statin associates could develop, an enhanced and prolonged physical stability of the vesicles could be ensured. © 2009 Elsevier B.V. All rights reserved.

Plazzo A.P.,Humboldt University of Berlin | Plazzo A.P.,Venetian Institute of Molecular Medicine | Hofer C.T.,Humboldt University of Berlin | Jicsinszky L.,CycloLab Cyclodextrin Research and Development Laboratory Ltd. | And 6 more authors.
Chemistry and Physics of Lipids | Year: 2012

Cyclodextrins (CDs) are widely used both in pharmaceutical applications to improve drug bioavailability and in cell biology as cholesterol-depleting and -delivering agents. Recently, it was shown that β-CD covalently coupled to fluorescent dextran polymers accumulates in cholesterol-enriched lysosomal storage organelles of human fibroblasts (Rosenbaum et al., 2010). By employing a methyl-βCD tagged with fluorescein (FMβCD), we have characterized the cellular trafficking of the CD in mammalian cell lines and its distribution into the endocytic compartments within the first minutes following addition to cells. FMβCD enters mammalian cells via endocytosis. The colocalization of FMβCD with transferrin-containing endosomes and the inhibition of FMβCD internalization by chlorpromazine or by an antisense RNA against clathrin heavy chain indicate that FMβCD is taken up via receptor-mediated, clathrin-dependent endocytosis. These results not only highlight the possibility of using CDs to target drugs intracellularly, but also warn about potential unwanted effects on cell physiology other than cholesterol extraction/loading at high concentrations, high temperatures and prolonged incubation times. © 2012 Elsevier Ireland Ltd.

Bikadi Z.,VirtuaDrug Ltd. | Fodor G.,University of Szeged | Hazai I.,VirtuaDrug Ltd. | Hari P.,Delta Informatika | And 5 more authors.
Chromatographia | Year: 2010

β-Lactams are one of the most widely used types of antibiotics. As β-Lactams are chiral, the enantiomeric separation of these compounds was investigated using cyclodextrins, frequently used as chiral separators. Molecular modeling methods were utilized in order to predict possible enantioseparation of four model compounds. Our results revealed that permethylated β-cyclodextrin is more likely to chirally separate the phenylazetidin derivates than the parent β-cyclodextrin. LC experiments using cyclodextrin as chiral stationary phase in most cases confirmed our prediction; however, more experiments and statistical evaluation of the results are needed in order to judge the prediction power of the molecular dynamic method. © 2010 Vieweg+Teubner Verlag | Springer Fachmedien Wiesbaden GmbH.

Vecsernyes M.,Debrecen University | Fenyvesi F.,Debrecen University | Bacskay I.,Debrecen University | Deli M.A.,Hungarian Academy of Sciences | And 2 more authors.
Archives of Medical Research | Year: 2014

Biological barriers are the main defense systems of the homeostasis of the organism and protected organs. The blood-brain barrier (BBB), formed by the endothelial cells of brain capillaries, not only provides nutrients and protection to the central nervous system but also restricts the entry of drugs, emphasizing its importance in the treatment of neurological diseases. Cyclodextrins are increasingly used in human pharmacotherapy. Due to their favorable profile to form hydrophilic inclusion complexes with poorly soluble active pharmaceutical ingredients, they are present as excipients in many marketed drugs. Application of cyclodextrins is widespread in formulations for oral, parenteral, nasal, pulmonary, and skin delivery of drugs. Experimental and clinical data suggest that cyclodextrins can be used not only as excipients for centrally acting marketed drugs like antiepileptics, but also as active pharmaceutical ingredients to treat neurological diseases. Hydroxypropyl-β-cyclodextrin received orphan drug designation for the treatment of Niemann-Pick type C disease. In addition to this rare lysosomal storage disease with neurological symptoms, experimental research revealed the potential therapeutic use of cyclodextrins and cyclodextrin nanoparticles in neurodegenerative diseases, stroke, neuroinfections and brain tumors. In this context, the biological effects of cyclodextrins, their interaction with plasma membranes and extraction of different lipids are highly relevant at the level of the BBB. © 2015 IMSS.

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