Synthesis and properties of siloxane-containing hybrid hydrogels with alpha,omega-functionalized macromers.

Siloxane-containing transparent hybrid hydrogels, coupled with high oxygen permeability and moderate equilibrium water content (EWC), were successfully obtained through free radical bulk copolymerization of hydrophobic and hydrophilic monomers. Due to obvious incompatibility of hydrophobic tris(trimethylsiloxy)-3-methacrryloxypropylsilane (TRIS) and hydrophilic 2-hydroxyehtyl methacrylate (HEMA) or N-vinyl pyrrolidone (NVP) monomers, alpha,omega-methacrylate terminated poly(dimethyl siloxane) (PDMS) macromer was employed as a compatibilizer in the formulations, resulting in high optical transmittance (> 90% at 400 nm) of the hybrid hydrogels. Although properties such as EWC and oxygen permeability of the hybrid hydrogels could be tailored over a wide range, the formulations with the PDMS macromer could not increase both EWC and oxygen permeability of the hybrid hydrogels without sacrificing one of them.

Biological activities of Fructus arctii fermented with the basidiomycete Grifola frondosa.

Fructus arctii extract containing phenolic glycosides was cultured with Grifola frondosa mycelia to produce β-glucosidase and its biological activities were studied. This β-glucosidase converted the glycosides (arctiin and caffeic acid derivatives) into aglycones (arctigenin and caffeic acid). Fermented Fructus arctii extract (G-FAE) with G.

Synthesis and properties of siloxane-containing hybrid hydrogels: optical transmittance, oxygen permeability and equilibrium water content.

Siloxane-containing hybrid hydrogels, coupled with optical transparency and moderate water content, have the advantage of a high oxygen permeability which gives rise to useful characteristics for extended wear contact lenses. To synthesize these hybrid hydrogels, free radical copolymerization of hydrophobic TRIS monomer/PDMS macromer with a hydrophilic monomer in a confined mold was studied. It proved that microphase separation of the resulting hybrid hydrogels, caused by inherent incompatibility between hydrophobic and hydrophilic monomers, could be controlled by either the hydrophobic/hydrophilic balance or molecular weight of PDMS macromer in the formulations, resulting in high optical transmittance (> 90%) at 400 nm.