Microspheres energy

Telegina et al. 72> showed that the activation energy for the viscous flow of a polyester oligomer filled with glass microspheres is 46.9 kJ/mol, while that of an epoxy oligomer is 78.3 kJ/mol. They also established the important fact that the addition of microspheres to an oligomer composition does not change the temperature viscosity coefficient. This means that the viscosity of a mixture with microspheres can be controlled, if the temperature dependence of the viscosity of the binder is known. 

Fig. 9 Schematic representation of the scintillation proximity assay of (S)-propanolol using imprinted microspheres. The light green area represents the aromatic antenna element, (a) The bound, tritium-labeled (S)-propranolol triggers the scintillator to generate a fluorescent light, (b) When the tritium-labeled (S)-propranolol is displaced by the unlabeled (S)-propranolol, it is too far away from the scintillator antenna to transfer efficiently the radiation energy therefore, no fluorescence can be generated (as described in [62])...

Proteinoid microspheres containing zinc hydrolyze the natural substrate, adenosine triphosphate (ATP) as well as the unnatural substrates, p-nitrophenylacetate or p-nitrophenyl phosphate. The significance resides in the fact that the energy for most biosyntheses is provided by the hydrolysis of ATP. Zinc, magnesium and other metal salts are known to catalyze the hydrolysis of ATP 10). Proteinoid microspheres containing zinc as a cofactor have an activity for hydrolysis of ATP 11 12). 

The intrinsic properties of proteinoids suggest a model of the assembly of a self-ordered structure representing the first cell. The more complex syntheses by the microspheres themselves require, in addition to enzymes, the provision of energy donor molecules such as ATP. Both ribosomal and aribosomal synthesis of peptides... 

ATP is converted to dinucleotide in magnesium-containing buffer without proteinoid in a yield of 0.7 %, but in the presence of basic proteinoid solution, acidic proteinoid microspheres, or acidic-basic proteinoid microspheres, the conversion to oligonucleotides is 2.2-2.3 %. With AMP instead of ATP no oligonucleotides result. The proteinoids are thus a model for proto-RNA polymerase activity, and ATP is reaffirmed as the source of energy for the synthesis of phosphodiester linkages 47). The microspheres of acidic proteinoid or of acidic-basic proteinoid synthesize di- and trinucleotides, while without proteinoid or basic proteinoid solution dinucleotide only results. Furthermore, the ratios of trinucleotides/dinucleotide are 0.5 for acidic-basic proteinoid microspheres, 0.2 for acidic proteinoid microspheres 47). 

Activation, dextran and inulin, 189-195 Activation energy of diffusion, 50-52 Additives, effect on percutaneous absorption of drugs in rabbits, 275 Agarose gel, use in liposomal drug delivery system, 267-270 Albumin microspheres intramuscular and intraarticular drug delivery, 204,206,211 preparation, 204,207/... 

During the late 1990s, Dr. Nastruzzi worked with Professor P. L. Luisi as a postdoctoral fellow at the Institute for Polymers at the Swiss Federal Institute of Technology in Zurich. As a postdoctoral fellow at the Department of Pharmaceutical Sciences at the University of Ferrara, he focused on the production and characterization of liposomes specially designed for retinoid delivery, as well as on biophysical studies and activity of in vitro cultured cell lines. In 1991, he obtained a researcher position in this department, where he devoted his energy to the production of microspheres, liposomes, and microemulsions for the controlled delivery of biological response modifiers. 

Fig. 13. Dependence of the owall change in free energy for phagocytosis of modified cdlulosic microspheres. (See Fig. 12. concerning the number in the Fig.)...

Samarium-153 hydroxyapatite microspheres ( SmM) have been shown to ablate effectively normal and inflamed equine synovium, with minimal radiation hazard to the horse or medical personnel (Yarbrough et al 2000a,b). Within the joint space, the synovial lining primarily absorbs the energy from the Sm emissions, thus allowing the clinician to target the synovium for destruction. When m is combined with hydroxyapatite, exposure to other organs or support persormel is minimized. 

Attention to catalyzed hydrolyses of phosphates was stimulated by the fact that transfer of phosphate from ATP is a reaction that serves as an ubiquitous source of energy in biological sysl3ms 42). Fox and Joseph 43) have found that ATP is hydrolyzed by zinc-containing proteinoid microspheres (Fig. 7 see p. 413), a special type of structural derivative of proteinoid. Microspheres that contain zinc cause the liberation of inorganic phosphate from ATP. The rate is appreciably greater than that of the spontaneous hydrolysis of ATP, but is about the same as that promoted by the equivalent amount of zinc 44). Rigorous aseptic precautions revealed that the activity was not attributable to microbial contaminants. 

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