betadex and ethylene-dimethacrylate

In order to investigate the effect of the linking spacer on the enantioseparation ability of β-cyclodextrin (β-CD) functionalized polymeric monoliths, three β-CD-functionalized organic polymeric monoliths with different spacer lengths were prepared by using three amino-β-CDs, i.e. mono-6-amino-6-deoxy-β-CD, mono-6-ethylenediamine-6-deoxy-β-CD, mono-6-hexamethylenediamine-6-deoxy-β-CD, as starting materials. These amino-β-CDs reacted with glycidyl methacrylate to produce functional monomers which were then copolymerized with ethylene dimethacrylate. The enantioseparation ability of the three monoliths was evaluated using 14 chiral acidic compounds, including mandelic acid derivatives, nonsteroidal anti-inflammatory drugs, N-derivatized amino acids, and chiral herbicides under optimum chromatographic conditions. Notably, the poly(GMA-NH2-β-CD-co-EDMA) column provides higher enantioresolution and enantioselectivity than the poly(GMA-EDA-β-CD-co-EDMA) and poly(GMA-HDA-β-CD-co-EDMA) columns for most tested chiral analytes. Furthermore, the enantioseparation performance of triazole-linker containing monoliths was compared to that of ethylenediamine-linker containing monoliths. The results indicate that the enantioselectivity of β-CD monolithic columns is strongly related to the length and type of spacer tethering β-CD to the polymeric support.

Topics: Amination; Amino Acids; Anti-Inflammatory Agents, Non-Steroidal; beta-Cyclodextrins; Chromatography, High Pressure Liquid; Epoxy Compounds; Ethylenediamines; Mandelic Acids; Methacrylates; Methylmethacrylates; Polymerization; Stereoisomerism; Triazoles

Low column efficiency for enantioseparations in capillary liquid chromatography (CLC) is a major problem commonly encountered with β-cyclodextrin (β-CD) functionalized polymer-based monoliths. In order to investigate the effect of the crosslinker type on enantioseparation performance, three commonly used crosslinkers, i.e. 1,4-bis(acryloyl)piperazine (PDA), ethylene dimethacrylate (EDMA) and N,N-methylenebisacrylamide (MBA), were copolymerized using the one-pot approach with glycidyl methacrylate-mono-6-amino-6-deoxy-β-CD (GMA-NH

Topics: Acrylamides; Amino Acids; beta-Cyclodextrins; Chromatography, High Pressure Liquid; Cross-Linking Reagents; Epoxy Compounds; Herbicides; Mandelic Acids; Methacrylates; Permeability; Phenylpropionates; Polymerization

A novel and facile one-pot copolymerization approach was developed for the preparation of a β-cyclodextrin (β-CD) functionalized organic polymer monolith. The proposed one-pot process involved two major reactions occurring in sequence in the same vial: (1) the ring opening reaction between the epoxy groups of glycidyl methacrylate (GMA) and the primary amino groups of ethylenediamine-β-CD (EDA-β-CD); (2) the copolymerization of glycidyl methacrylate-ethylenediamine-β-CD (GMA-EDA-β-CD) and ethylene dimethacrylate (EDMA) using 2,2'-azobisisobutyronitrile (AIBN) as the polymerization initiator. This approach avoids the time-consuming post-polymerization derivatization of the traditional two-step strategy. Compared to the previously reported two-step strategy, the monolith prepared by this one-pot method exhibited higher β-CD ligand density and better column efficiency in HPLC. Satisfactory column permeability and separation selectivity were also obtained on the optimized poly(GMA-EDA-β-CD-co-EDMA) monolithic column. Additionally, the column was also applied to the enantioseparation of some racemic acidic compounds with promising results.

Topics: beta-Cyclodextrins; Chromatography, High Pressure Liquid; Epoxy Compounds; Ethylenediamines; Isomerism; Methacrylates; Microscopy, Electron, Scanning

Applications of molecularly imprinted polymer (MIPs), is rapidly increasing, especially in the drug delivery field. Molecularly imprinted polymers are the molecular traps, which can entrap the specific molecule and also control its release. Polymer complexes were prepared with and without propranolol HCl as templates, MAA (methacrylic acid) as monomer and EGDMA (ethyleneglycol dimethacrylate) as crosslinker by solvent polymerization technique. Drug release pattern from these polymer complexes were compared and maximum drug release in 12 h was consider to optimize the ratio of MAA and EGDMA. Since, the maximum propranolol HCl release from polymer complex was low (62.15%) in optimized batch, inclusion complex of drug with β-cyclodextrin were prepared for the higher drug release (80.32%). The selected polymer complexes were treated with methanol for complete removal of the drug to form MIPs. These MIPs were reloaded with the drug and subjected for drug release. The release patterns from reloaded MIP's were observed to be slightly quicker than their corresponding MIP's.

Topics: Adrenergic beta-Antagonists; beta-Cyclodextrins; Delayed-Action Preparations; Drug Carriers; Methacrylates; Molecular Imprinting; Propranolol; Solubility

An organic polymeric monolithic disk was prepared by situ polymerization of glycidyl methacrylate (GMA) and ethylene dimethacrylate (EDMA) in a binary porogenic solvent consisting 1-propanol and 1,4-butanediol, then modified by a reaction with beta-cyclodextrin (beta-CD). The beta-CD modified disk can be used as a solid substrate and solid phase extraction (SPE) membrane for solid phase extraction-room temperature phosphorescence (SPE-RTP). The room temperature phosphorescence (RTP) behaviors of 14 organic compounds on the beta-CD modified disk were examined. The results indicated that phenanthrene, 7,8-benzoquinoline, carbazole, fluorene, 3-indoleacetic acid and 1-naphthylacetic acid can emit strong RTP, and the limits of detection (LOD) were found to be 6.5 x 10(-10)-3.0 x 10(-9) mol mL(-1). Used as solid phase extraction membrane, the modified disk could selectively enrich compounds with three rings such as phenanthrene, 7,8-benzoquinoline, carbazole and fluorene. After solid phase extraction, LODs of four compounds were decreased to 4.0 x 10(-12)-6.4 x 10(-11) mol mL(-1). The method was applied to the determination of fluorene and phenanthrene in biosamples with satisfactory results.

Topics: beta-Cyclodextrins; Epoxy Compounds; Fluorenes; Luminescent Measurements; Methacrylates; Phenanthrenes; Polymers; Solid Phase Microextraction