The original technologies of growing silica films, impregnated with 7-dehydrocholesterol (provitamin D3) on quartz substrates and free transparent films on the basis of polyvinyl alcohol and polyvinyl butyral have bee...The original technologies of growing silica films, impregnated with 7-dehydrocholesterol (provitamin D3) on quartz substrates and free transparent films on the basis of polyvinyl alcohol and polyvinyl butyral have been developed. Provitamin D photoisomerization in the films under UVB irradiation was investigated by UV absorption spectroscopy. Remarkable changes in the absorption spectrum of 7-DHC were observed in silica and polyvinyl alcohol films as com-pared with ethanol solution, only in polyvinyl butyral film the spectrum was very nearly, while the spectral kinetics of 7-DHC photoisomerization in all the films was different from ethanol. We suggest that several films have potential as UV dosimeters to measure accumulated ‘antirachitic’ UV dose in the same manner as erythemic UV dose is measured by commonly used polysulphone film.展开更多
Study of interfacial processes between incorporated biomolecules and hydrogel matrix is of primary importance for the application of synthetic hydrogels as biomaterials, sensors, etc. Their hydrophilic nature, however...Study of interfacial processes between incorporated biomolecules and hydrogel matrix is of primary importance for the application of synthetic hydrogels as biomaterials, sensors, etc. Their hydrophilic nature, however, hampers fat-soluble biomolecule incorporation. We synthesized N-isopropylacrylamide (NIPAAm)- and Acrylamide (AA)-based hydrogels with hydrophilic-lipophilic balance that under specific conditions permit homogeneous incorporation of provitamins D3(7-dehydrocholesterol) and D2(ergosterol) dissolved in ethanol. Similarity of provitamins D photoisomerization in such hydrogel matrices with the photoreaction in ethanol shows great potential of the novel material for personal dosimetry of biologically active ‘antirachitic’ UV radiation.展开更多
文摘The original technologies of growing silica films, impregnated with 7-dehydrocholesterol (provitamin D3) on quartz substrates and free transparent films on the basis of polyvinyl alcohol and polyvinyl butyral have been developed. Provitamin D photoisomerization in the films under UVB irradiation was investigated by UV absorption spectroscopy. Remarkable changes in the absorption spectrum of 7-DHC were observed in silica and polyvinyl alcohol films as com-pared with ethanol solution, only in polyvinyl butyral film the spectrum was very nearly, while the spectral kinetics of 7-DHC photoisomerization in all the films was different from ethanol. We suggest that several films have potential as UV dosimeters to measure accumulated ‘antirachitic’ UV dose in the same manner as erythemic UV dose is measured by commonly used polysulphone film.
文摘Study of interfacial processes between incorporated biomolecules and hydrogel matrix is of primary importance for the application of synthetic hydrogels as biomaterials, sensors, etc. Their hydrophilic nature, however, hampers fat-soluble biomolecule incorporation. We synthesized N-isopropylacrylamide (NIPAAm)- and Acrylamide (AA)-based hydrogels with hydrophilic-lipophilic balance that under specific conditions permit homogeneous incorporation of provitamins D3(7-dehydrocholesterol) and D2(ergosterol) dissolved in ethanol. Similarity of provitamins D photoisomerization in such hydrogel matrices with the photoreaction in ethanol shows great potential of the novel material for personal dosimetry of biologically active ‘antirachitic’ UV radiation.