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Adsorption models in chiral chromatography. J Chromatogr A 2012; 1269:3-25. [DOI: 10.1016/j.chroma.2012.08.096] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2012] [Revised: 08/26/2012] [Accepted: 08/28/2012] [Indexed: 12/20/2022]
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Salwiński A, Roy V, Agrofoglio LA, Delépée R. In Situ One-Step Method for Synthesis of “Click”-Functionalized Monolithic Stationary Phase for Capillary Electrochromatography. MACROMOL CHEM PHYS 2011. [DOI: 10.1002/macp.201100526] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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Xu J, Li X, Sun F, Cao P. PVA hydrogels containing beta-cyclodextrin for enhanced loading and sustained release of ocular therapeutics. JOURNAL OF BIOMATERIALS SCIENCE-POLYMER EDITION 2010; 21:1023-38. [PMID: 20507706 DOI: 10.1163/156856209x463690] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
The purpose of this work is to develop poly(vinyl alcohol) (PVA) hydrogels incorporating large amounts of beta-cyclodextrin (beta-CD) in order to improve ocular drug loading and to sustain drug release. First, the mono-methacrylated-beta-CD monomer (MA-beta-CD) and the methacrylated-PVA macromer (PVAMA), with a substitution degree of 7%, are synthesized and characterized. Then, the poly(methacrylated-PVA-co-mono-methacrylated-beta-cyclodextrin) (pPVA-beta-CD) hydrogels are prepared by UV-induced polymerization of MA-beta-CD and PVAMA. The highest amount of beta-CD incorporated into the hydrogels is 30 wt%. The hydrogels are further characterized by transmittance, FT-IR, equilibrium swelling ratio (ESR), tensile tests and protein deposition. The results show that pPVA-beta-CD hydrogels possess good transmittance, while the incorporation of beta-CD in the hydrogels improves the tensile strength and decreases the ESR and protein deposition. Finally, puerarin and acetazolamide are used as models to evaluate the drug loading and in vitro release behavior of the pPVA-beta-CD hydrogels. The results indicate that the amount of drug loaded into the pPVA-beta-CD hydrogels progressively increases, while the release rate decreases with increasing beta-CD content. In particular, incorporation of beta-CD efficiently decreases the initial burst release of acetazolamide, while the release, which is almost linear, is sustained for 15 days. The pPVA-beta-CD hydrogels have potential applications as biomedical devices for sustained release of ocular drugs.
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Affiliation(s)
- Jinku Xu
- Biomaterials and Drug Delivery Laboratories, School of Chemistry and Chemical Engineering, Southeast University, Nanjing 211189, P. R. China
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Shpigun OA, Ananieva IA, Budanova NY, Shapovalova EN. Use of cyclodextrins for separation of enantiomers. RUSSIAN CHEMICAL REVIEWS 2007. [DOI: 10.1070/rc2003v072n12abeh000817] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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Ylä-Mäihäniemi PP, Williams DR. A comparison of frontal and nonfrontal methods for determining solid-liquid adsorption isotherms using inverse liquid chromatography. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2007; 23:4095-101. [PMID: 17328566 DOI: 10.1021/la0632631] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/14/2023]
Abstract
Inverse liquid chromatography (ILC) has been used to determine experimental isotherms for the equilibrium adsorption of cyclohexanone onto a silica (61.8 m(2)/g) from hexane using the peak maximum (PM), elution by characteristic point (ECP), frontal analysis (FA), and frontal analysis by characteristic point (FACP) methods. Isotherms obtained using these four approaches gave good internal agreement, as well as being in good agreement with classically determined isotherms. Columns were successfully packed using a dry powder packing method with 9 microm diameter silica particles, and excellent intercolumn and instrument to instrument reproducibility was obtained for PM isotherms. The theoretical background to the PM, ECP, FA, and FACP methods, as well as the practical facets of isotherm determination using these methods, is outlined in this work.
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Affiliation(s)
- Pirre P Ylä-Mäihäniemi
- Department of Chemical Engineering, Imperial College of Science, Technology and Medicine, Prince Consort Road, South Kensington, London SW7 2AZ, United Kingdom
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Constantin M, Fundueanu G, Bortolotti F, Cortesi R, Ascenzi P, Menegatti E. Preparation and characterisation of poly(vinyl alcohol)/cyclodextrin microspheres as matrix for inclusion and separation of drugs. Int J Pharm 2005; 285:87-96. [PMID: 15488682 DOI: 10.1016/j.ijpharm.2004.07.025] [Citation(s) in RCA: 56] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2004] [Revised: 07/13/2004] [Accepted: 07/22/2004] [Indexed: 11/29/2022]
Abstract
Poly(vinyl alcohol) (PVA) microspheres containing cyclodextrin (CD) were obtained by chemical cross-linking with glutaraldehyde of an acidified mixture solution of PVA and alpha-, beta- or gamma-CD. The amount of linked CD in microspheres, estimated by tetrazolium blue method, decreases in the order beta- > gamma- > alpha-CD. The dimensions of PVA/gamma-CD microspheres are much higher than those of PVA/alpha- and beta-CD. The cross-linking density of microspheres was estimated by the amount of iodine retained by the polymer matrix. The pore size as well as the porous volume of PVA/CD microspheres decrease significantly on increasing the amount of glutaraldehyde, but are enough large to permit the access of drugs to the CD cavity. In order to test the PVA/CD microsphere inclusion ability, the microspheres were packed in a glass column and the liquid chromatographic behaviour by isocratic elution of different drugs or typical organic compounds, taken as model drugs, was investigated.
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Affiliation(s)
- Marieta Constantin
- Department of Pharmaceutical Sciences, University of Ferrara, Via Fossato di Mortara, 19 44100 Ferrara, Italy
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Gazpio C, Sánchez M, García-Zubiri IX, Vélaz I, Martínez-Ohárriz C, Martín C, Zornoza A. HPLC and solubility study of the interaction between pindolol and cyclodextrins. J Pharm Biomed Anal 2005; 37:487-92. [PMID: 15740908 DOI: 10.1016/j.jpba.2004.11.008] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2004] [Revised: 11/03/2004] [Accepted: 11/03/2004] [Indexed: 11/16/2022]
Abstract
The complexation with beta-cyclodextrin (beta-CD) has been investigated using reversed-phase liquid chromatography. The compounds tested have been pindolol and, for comparison purposes, indole and 4-methoxyindole. The retention behaviour has been analysed on a Kromasil 100 C18 column and the mobile phase used was methanol-pH 6 phosphate buffer (15/85v/v) in which beta-CD was incorporated as a mobile phase additive. The decrease in the retention times with increasing concentrations of beta-CD enables the determination of the apparent stability constants of the complexes. In addition, the low solubility of pindolol, a weak base, in pH 12 aqueous solution has been improved by complexation with different cyclodextrins. The solubility enhancements with 1.4 x 10(-2) M beta-, hydroxypropyl-beta, and gamma-CD have been 1.9, 1.8 and 1.4-fold, respectively, with 2.4 x 10(-2) M methyl-beta-CD it was 2.8-fold whilst no effect was observed with alpha-CD. The stability constants of the complexes at pH 12 have been determined from the solubility isotherms.
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Affiliation(s)
- Carmen Gazpio
- Departamento de Química y Edafología, Facultad de Ciencias, Universidad de Navarra, Irunlarrea s/n, Pamplona 31080, Spain
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Piletsky SA, Mijangos I, Guerreiro A, Piletska EV, Chianella I, Karim K, Turner APF. Polymer Cookery: Influence of Polymerization Time and Different Initiation Conditions on Performance of Molecularly Imprinted Polymers. Macromolecules 2005. [DOI: 10.1021/ma048021r] [Citation(s) in RCA: 48] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Sergey A. Piletsky
- Institute of BioScience and Technology, Cranfield University, Silsoe, Bedfordshire, MK45 4DT, U.K
| | - Irene Mijangos
- Institute of BioScience and Technology, Cranfield University, Silsoe, Bedfordshire, MK45 4DT, U.K
| | - Antonio Guerreiro
- Institute of BioScience and Technology, Cranfield University, Silsoe, Bedfordshire, MK45 4DT, U.K
| | - Elena V. Piletska
- Institute of BioScience and Technology, Cranfield University, Silsoe, Bedfordshire, MK45 4DT, U.K
| | - Iva Chianella
- Institute of BioScience and Technology, Cranfield University, Silsoe, Bedfordshire, MK45 4DT, U.K
| | - Kal Karim
- Institute of BioScience and Technology, Cranfield University, Silsoe, Bedfordshire, MK45 4DT, U.K
| | - Anthony P. F. Turner
- Institute of BioScience and Technology, Cranfield University, Silsoe, Bedfordshire, MK45 4DT, U.K
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Skavrada M, Jandera P, Cherrak DE, Aced A, Guiochon G. Adsorption isotherms and retention behavior of 1,1′-bis(2-naphthol) on CHIRIS AD1 and CHIRIS AD2 columns. J Chromatogr A 2003; 1016:143-54. [PMID: 14601835 DOI: 10.1016/s0021-9673(03)01325-6] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
Abstract
The separation of the atropoisomers of 1,1'-bis(2-naphthol) was studied on CHIRIS AD1 and CHIRIS AD2, two Pirkle-type chiral stationary phases. Satisfactory selectivity was found only on CHIRIS AD2. The ternary mobile phases comprised hexane, dichloromethane and methanol. The effects of their composition and of the temperature on the retention under analytical conditions and on the single-component and competitive isotherms were investigated. The retention of the R- and S-isomers on CHIRIS AD1 and CHIRIS AD2 is controlled by the enthalpic contribution to adsorption, but the effect of the mobile phase on the retention should be attributed mainly to the entropic contribution. The adsorption of the less retained R-isomer is controlled by the achiral interactions, which are the same as for the S-isomer. The single-component and competitive isotherms of the R- and S-isomers are adequately described by the sum of a Langmuir term for the achiral contribution to adsorption and a linear-term characterising the selective or chiral adsorption of the S-isomer in the concentration range experimentally available, i.e. within the solubility limit of 1,1'-bis(2-naphthol).
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Affiliation(s)
- Michal Skavrada
- Department of Analytical Chemistry, University of Pardubice, Nám. Cs. legií 565, CZ 532, 10 Pardubice, Czech Republic
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Thuaud N, Sebille B, Renard E. Insight into the chiral recognition of warfarin enantiomers by epichlorhydrin/beta-cyclodextrin polymer-based supports: determination of stoichiometry and stability of warfarin/beta-cyclodextrin polymer complexes. JOURNAL OF BIOCHEMICAL AND BIOPHYSICAL METHODS 2002; 54:327-37. [PMID: 12543508 DOI: 10.1016/s0165-022x(02)00125-2] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
The complexation of warfarin (W) enantiomers by a hydrosoluble high-molecular-weight beta-cyclodextrin/epichlohydrin polymer (EP/beta-CD polymer) was studied using HPLC with a mobile phase of methanol/0.1 M Na acetate/acetic acid (pH 4) at 22 degrees C. It was found that the complexes (W/beta-CD unit) have a 1:1 stoichiometry. The stability constants of the complex involving each enantiomer and the polymer beta-CD units were determined in the mobile phase, and the highest stability of the complex (S-warfarin/beta-CD unit) was observed. From the chromatographic separations of warfarin enantiomers on different beta-CD or its derivative supports, we have deduced the role of the simultaneous presence of several glyceryl (-O-CH(2)-CHOH-CH(2)-O-) and dihydroxypropyl (-O-CH(2)-CHOH-CH(2)OH) groups on one beta-CD ring in promoting the chiral recognition of warfarin enantiomers.
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Affiliation(s)
- Nicole Thuaud
- Laboratoire de Recherche sur les Polymères, Université de Paris XII, UMR CNRS C 7581, 2-8 rue Henri Dunant, F-94320 Thiais, France
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Bojarski J. Stereoselective chromatography of cardiovascular drugs: an update. JOURNAL OF BIOCHEMICAL AND BIOPHYSICAL METHODS 2002; 54:197-220. [PMID: 12543499 DOI: 10.1016/s0165-022x(02)00143-4] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
This review reports the latest achievements in chromatographic enantioseparations of various classes of cardiovascular drugs and selected applications of these methods in pharmaceutical and clinical analysis. The use of these drugs as test compounds for new chiral stationary phases and different parameters of chromatographic processes is also presented.
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Affiliation(s)
- Jacek Bojarski
- Department of Organic Chemistry, Medical College, Faculty of Pharmacy, Jagiellonian University, Medyczna 9, 30-688 Cracow, Poland.
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Piletsky SA, Piletska EV, Karim K, Freebairn KW, Legge CH, Turner APF. Polymer Cookery: Influence of Polymerization Conditions on the Performance of Molecularly Imprinted Polymers. Macromolecules 2002. [DOI: 10.1021/ma0205562] [Citation(s) in RCA: 83] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Sergey A. Piletsky
- Institute of BioScience and Technology, Cranfield University, Silsoe, Bedfordshire, MK45 4DT, UK, and GlaxoSmithKline Research and Development, Gunnels Wood Road, Stevenage, Herts, SG1 2NY, UK
| | - Elena V. Piletska
- Institute of BioScience and Technology, Cranfield University, Silsoe, Bedfordshire, MK45 4DT, UK, and GlaxoSmithKline Research and Development, Gunnels Wood Road, Stevenage, Herts, SG1 2NY, UK
| | - Kal Karim
- Institute of BioScience and Technology, Cranfield University, Silsoe, Bedfordshire, MK45 4DT, UK, and GlaxoSmithKline Research and Development, Gunnels Wood Road, Stevenage, Herts, SG1 2NY, UK
| | - Keith W. Freebairn
- Institute of BioScience and Technology, Cranfield University, Silsoe, Bedfordshire, MK45 4DT, UK, and GlaxoSmithKline Research and Development, Gunnels Wood Road, Stevenage, Herts, SG1 2NY, UK
| | - Coulton H. Legge
- Institute of BioScience and Technology, Cranfield University, Silsoe, Bedfordshire, MK45 4DT, UK, and GlaxoSmithKline Research and Development, Gunnels Wood Road, Stevenage, Herts, SG1 2NY, UK
| | - Anthony P. F. Turner
- Institute of BioScience and Technology, Cranfield University, Silsoe, Bedfordshire, MK45 4DT, UK, and GlaxoSmithKline Research and Development, Gunnels Wood Road, Stevenage, Herts, SG1 2NY, UK
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