The present study describes the immobilization of horseradish peroxidase (HRP) on magnetite-modified polyaniline (PANImG) activated with glutaraldehyde. After the optimization of the methodology, the immobilization of HRP on PANImG produced the same yield (25%) obtained for PANIG with an efficiency of 100% (active protein). The optimum pH for immobilization was displaced by the effect of the pa...

Yeast alcohol dehydrogenase is an example of a protein in which the K-m for substrate is substantially decreased by the presence of glycerol. The polyol has the effect at pH 8.0 or above of decreasing K-m and K-s for substrate and of altering both the protein's intrinsic fluorescence and ultraviolet absorption difference spectrum. The relationship between each of thse parameters and glycerol co...

In this study, gelatin microspheres containing lactic acid were prepared by the polymerization technique using glutaraldehyde as the cross-linking agent. Dried microspheres were loaded by immersing them in an aqueous solution of lactic acid. In order to prepare microspheres with an appropriate drug release profile, the effect of time of cross-linking and the amount of cross-linking agent on the...

A template-directed method for the synthesis and organization of partially oxidized polypyrrole (PPy) nanoscale arrays within the solvent channels of glutaraldehyde-cross-linked lysozyme single crystals is presented. Macroscopic single crystals of the periodically arranged protein-polymer superstructure are electrically conductive, insoluble in water and organic solvents, and display increased ...

Crosslinking and the resultant changes in mechanical properties have been shown to influence cellular activity within collagen biomaterials. With this in mind, we sought to determine the effects of crosslinking on both the compressive modulus of collagen-glycosaminoglycan scaffolds and the activity of osteoblasts seeded within them. Dehydrothermal, 1-ethyl-3-3-dimethyl aminopropyl carbodiimide ...

The 9 + 2 array of ciliary and fiagellar tubules was described in the early days of electron micros-copy when osmium tetroxide was the standard fixative. Cytoplasmic microtubules, which are not generally in evidence after osmium tetroxide fixation, were rarely seen until after the advent of aldehyde fixatives. In some glutaraldehyde-OsO4-fixed material, flagellar and ciliary tubules are

Hydrostatic pressure can be used to perturb the ribosome-ribosomal subunit equilibrium. We have used glutaraldehyde fixation and subsequent sucrose gradient analysis to determine the equilibrium concentrations of Escherichia coli 70 S, 50 S, and 30 S particles at pressures from 1 to 1400 atm. This method is shown to be sufficiently rapid and free of interfering ribosomal aggregation artifacts w...

CAMILLO PERACCHIA and BRANT S. MITTLER . From the Department of Anatomy, Duke University Medical Center, Durham, North Carolina 27706, and the Department of Physiology, University of Rochester, School of Medicine and Dentistry, Rochester, New York 14642 . Dr. Peracchia's present address is the Department of Physiology, University of Rochester, School of Medicine and Dentistry, Rochester, New Yo...

The fine structure of the Z-disk in rat striated muscle has been found to be dependent upon the manner of its fixation. Material primarily fixed in osmium tetroxide shows a square or ' woven' lattice in transverse sections, with a spacing of around 22 ran, and with its axes off-set by 45° from the axes of alignment of the files of I-filaments prior to their entry into the Z-disk. In longitudina...

Intact human erythrocytes were cross-linked with glutaraldehyde (GA) or dimethyladipimidate (DMA) and tested for their ability to bind [125I]-IgG anti-Rh0(D) and to undergo antibody-mediated hemagglutination. There was no decrease in antibody binding after treatment with GA concentrations up to 1.25% and DMA concentrations up to 1%. Red cells treated with these concentrations of GA and DMA did ...