betadex and hydroxyethyl-methacrylate

The low abundance of glycoproteins in complex samples results in the prerequisite role of efficient and selective enrichment of them. In the present work, we designed a new kind of glycosylation poly(hydroxyethyl methacrylate-pentaerythritol triacrylate) monolith functionalized with glycocluster grafted β-cyclodextrin for the enrichment of glycoproteins. The introduced modifiers endowed the monolithic material with enhanced hydrophilicity and surface area, which benefitted to improve the enrichment selectivity and extraction efficiency for glycopeptides. By combining with MALDI-MS detections, 22 glycopeptides from horseradish peroxidase digest were captured with the developed monolith while 4 glycopeptides were enriched by commercially available agarose matrix column. LOD of 6.6pmol was attained. When applied to the enrichment of glycopeptides from complex protein samples and human lymphoma (U937) cell line, the prepared monolith exhibited high selectivity for glycopeptides.

Topics: beta-Cyclodextrins; Glycoproteins; Glycosylation; Humans; Hydrophobic and Hydrophilic Interactions; Methacrylates; Polymers; Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization

Copolymerization of hydroxyethyl methacrylate (HEMA) with a methacrylated-derivative of beta-cyclodextrin (beta-CD) was evaluated as a way to obtain hydrogels with tunable mechanical and drug loading and release properties, particularly for preparing medicated soft contact lenses. A fully methacrylated beta-CD monomer was synthesized and added to the HEMA and cross-linker solution at concentrations ranging from 0.042 to 0.333 g ml(-1) (i.e. 0.23-1.82 mol.%). Thermal polymerization led to transparent hydrogels with a degree of conversion above 74%, which showed a high cytocompatibility and did not induce macrophage response. The greater the content in methacrylated beta-CD was, the higher the glass transition temperature, the lower the degree of swelling and free water proportion, and the greater the storage and loss moduli of the swollen disks. These findings are directly related to the increase in the degree of cross-linking caused by the methacrylated beta-CD. Loading studies were carried out with hydrocortisone and acetazolamide, both able to form complexes with CDs in water and in lacrimal fluid. Hydrocortisone loading progressively decreased as the content in methacrylated beta-CD rose due to a decrease in the volume of aqueous phase of the hydrogel. Acetazolamide loading showed a maximum for an intermediate content in beta-CD (0.125-0.167 g ml(-1)) owing to a balance between complexation with beta-CD and hydrogel mesh size. The hydrogels sustained drug delivery for several days, the acetazolamide release rate being dependent on the beta-CD content. An adequate selection of the content in beta-CD enables pHEMA-co-beta-CD hydrogels suitable for specific biomedical applications to be obtained.

Topics: Acetazolamide; Animals; beta-Cyclodextrins; Biocompatible Materials; Biomechanical Phenomena; Cell Line; Cell Survival; Drug Delivery Systems; Hydrocortisone; Hydrogels; Methacrylates; Mice; Propylene Glycols; Rheology; Solubility; Spectroscopy, Fourier Transform Infrared; Water