Glutaraldehyde method

Table 6 Conjugation of an amino-containing hapten to a protein using the glutaraldehyde method...

The following procedure utilizes the one-step glutaraldehyde method. A two-step method may be used to somewhat limit polymerization of the conjugate (Chapter 20, Section 1.2). Varying the pH and the amount of glutaraldehyde added to the reaction can control the yield and molecular weight of the conjugates formed. 

The experimental conditions for the covalent bonding of fluorescent molecules and antibodies to the spheres by means of the cyanogen bromide, carbodiimide and glutaraldehyde methods. 

Conjugation of alkaline phosphatase to protein A by the two-step glutaraldehyde method (Engvall, 1978)... 

The activity after immobilization is depending on the method used. The weakest loss of activity after immobilization was obtained with the coreticulation by the BSA-glutaraldehyde method. Heating of the carn enan gel can explain the important loss of photosynthetic activity. The presence of BSA in the mixture with the urethane polymer produced an increase in the activity after immobilization. This result confirms the protective role of proteins. 

The immobilization of the photosynthetic material also increases the operational activity. Oxygen production by native and immobilized thylakoids was continuously monitored at 20°C under saturating illumination. After 50 min, the native thylakoids are completely inactive while the thylakoids immobilized according to different procedures keep some residual activity. If these results are compared with those of stor e stability in dark, it becomes obvious that the continuous use under illumination accelerated the inactivation rate by a factor of about 300. Moreover, among the immobilization procedures used, the BSA-glutaraldehyde method presented the best protection against photoinactivation. ... 

Lipase immobilized on SMOF by glutaraldehyde method Lipase [166] activity tested by determination of p-nitrophenyl butyrate hydrolysis products SMOF evaluated for synthesis of butyl laurate from lauric acid and n-butanol in n-hexane and n-heptane percentage yield up to 99% with 38 s residence time at a flow rate of 1 pl/min... 

Because enzymes can be intraceUularly associated with cell membranes, whole microbial cells, viable or nonviable, can be used to exploit the activity of one or more types of enzyme and cofactor regeneration, eg, alcohol production from sugar with yeast cells. Viable cells may be further stabilized by entrapment in aqueous gel beads or attached to the surface of spherical particles. Otherwise cells are usually homogenized and cross-linked with glutaraldehyde [111-30-8] to form an insoluble yet penetrable matrix. This is the method upon which the principal industrial appHcations of immobilized enzymes is based. 

Glutaraldehyde in air Lab method using high performance liquid chromatography 93... 

Similarly, a composite of hydroxyapatite and a network formed via cross-linking of chitosan and gelatin with glutaraldehyde was developed by Yin et al. [ 169]. A porous material, with similar organic-inorganic constituents to that of natural bone, was made by the sol-gel method. The presence of hydroxyapatite did not retard the formation of the chitosan-gelatin network. On the other hand, the polymer matrix had hardly any influence on the high crystallinity of hydroxyapatite. 

The preparation of microspheres can be accomplished by either of two methods thermal denaturation, in which the microspheres are heated to between 95 and 170°C, and chemical crosslinking with glutaraldehyde in a water-in-oil emulsion. Well-defined microspheres can be easily prepared using these methods in large batches which are usually physically and chemically stable. Newer preparation methods for the preparation of albumin microspheres have been described by several authors (84-88). 

The cross-linking method relies on bifimctional reagents to form intermolecular linkages between the enzyme molecules to render them insoluble. Often albumin is added as an extender and glutaraldehyde is most commonly employed. This material can then be either formed as a free standing membrane or applied to the inner surface of the dialysis membrane... 

Colorimetry. Laboratory data on the persistence of biocides formulated in glutaraldehyde and acrolein are available [1260]. A colorimetric general aldehyde detection method based on m-phenylenediamine was used. Such studies follow the demand for better understanding of ecologic systems in the aspect of environmental protection. 

A disadvantage of the glutaraldehyde condensation method is that dimers of the hapten and polymers of carrier protein may also form. To overcome this problem, the reaction time is limited to 2-3 h, or an excess of an amine-containing compound, e.g., lysine or cysteamine hydrochloride, is added. A two-step approach also minimizes dimerization. ... 

Purified MeHNL was crystallized by the sitting-drop vapor-diffusion method. The 10-20 mm bipyramidal crystals formed were cross-linked with glutaraldehyde and used as biocatalyst for the synthesis of optically active cyanohydrins. The cross-linked crystals were more stable than Celite-immobilized enzymes when incubated in organic solvents, especially in polar solvents. After six consecutive batch reactions in dibutyl ether, the remaining activity of the cross-linked crystals was more than 70 times higher than for the immobilized enzymes. Nevertheless, the specific activity of the cross-linked crystals per milligram protein was reduced compared with the activity of Celite-immobilized enzymes [53],... 

In their method, after co-adsorption of enzymes and magnetite nanoparticles, enzyme molecules were cross-linked via glutaraldehyde treatment. The HMMS... 

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