Cyanuric chloride immobilization

Cyanuric chloride method, for covalent ligand immobilization, 6 396t Cycads, in nitrogen fixation, 2 7 300 Cyclamate, 22 42 24 234, 236 sweeteners, 2 513-514 Cyclamen aldehyde, aroma chemical derived from toluene, 3 234 Cyclams, 24 41—42... 

The surface of the porous silicon chip offers multiple possibilities for the covalent coupling of functional groups. Thus, functionalization of a DIOS target by immobilization of trypsin was described by Xu et al. [21]. The enzyme was immobilized using cyanuric chloride as coupling agent following an amino-functionalization (Fig. 8.11). 

Several other methods are proposed, such as use of coulomb force between anionic DNA and cationic particle (7), use of biospecific affinity between biotin-labeled DNA and avidin-carrying particle (8), etc. Other methods for immobilization of DNA on the particle include reactions using cyanogen bromide, glutaraldehyde, and cyanuric chloride (9). 

Amines. The amines used to sequentially substitute the chlorines of cyanuric chloride free or immobilized onto agarose vary from case to case. In general, the amines should be dissolved in an appropriate buffer, either an aqueous solution or an organic solvent such as dimethylformamide. Take precautions related to the re-ac-tivity of each compound, which in some cases may involve the protection of... 

Catalase can be easily immobilized on a hydrolysed vinyl acetate-cyanuric chloride membrane ... 

Fig. 7. Effect of sucrose concentration on thermometric signal in steady-state. Invertase was immobilized on bead cellulose activated by cyanuric chloride [27]...

Cyanuric chloride in activation of inorganic supports for enzyme immobilization 80MI4. 

Galactosidase has been attached to glass in this way.56 The immobilized enzyme is useful in removing lactose from milk, for the benefit of those persons who are intolerant of lactose. A similar technique was used to attach glucose oxidase to magnetite (I i O-i) particles, starting with a trimethoxysilane.57 This permits easy separation with a magnet. The immobilized enzyme was 50% less active than the native enzyme, but kept 95% of its activity after 9 months at 4°C. Another way to attach an enzyme to a support is to treat the metal oxide support first with 2,4,6-trichloro 1,3,5 triazine (cyanuric chloride) (5.18), then with the enzyme.58 This was done on both alumina and on silica. 

The use of cyanuric chloride to modify carbon surfaces occurs in two steps. First the surface is reacted with the cyanuric chloride to produce an activated surface. Then this activated surface is further reacted to attach the group of interest (see figure 6.5). The immobilized cyanuric group is reactive towards alcohols and amines [18] and has been used to attach enzymes [19], as well as... 

Fluoresceinamine immobilized into polyfvinyl alcohol) membranes using cyanuric chloride and glutaraldehyde on fiber optic bundles pH [41]... 

Procedures. The first step in indicator immobilization is to react poly(vinyl alcohol) (PVOH) with cyanuric chloride in acetone/water as described earlier (1). The PVOH/cyanuric chloride conjugate is then reacted with 10 mLs of a solution of indicator in acetone. For pH sensing, the indicator solution contained 100 mg of fluoresceinamine. For Mg(II) sensing, the indicator solution typically contained 100 mg... 

In other techniques, the protein may be bound by some copolymer of maleic anhydride, where the anhydride groups react with some available amine groups on the enzyme [42]. Other techniques may utilize cyanuric chloride attached to polysaccharides for immobilization [42] ... 

Figure 3.14 Fluorescence emission of frans-4-dimethylamino-4 -amino-stilbene in a free state in 8 x 10 M toluene solution (closed squares) and an immobilized state cross-linked with cyanuric chloride to the coating BSA protein in toluene (open squares) and in glycerin (rhombus) [55], (Reproduced with permission from Elsevier.)...

A series of substituted trans-stilbene derivatives have been prepared and immobilized on a quartz surface [19]. Several immobilization methods have been tried including the silanization technique, cross-linking with cyanuric chloride, surface activation with cyanogen bromide, and surface smoothing with coating proteins. 

The first paper on a CME for electrocatalytic NADH oxidation reported by Tse and Kuwana in 1978 [159] was based on two primary amine containing o-quinone derivatives, dopamine or 3,4-dihydroxybenzylamine, that could be covalently immobilized onto the surface of cyanuric chloride-activated GC electrodes forming a monolayer on the electrode... 

Enzymes have also been immobilized on collagen membrane after its stepwise modification to esters, hydrazides and azides [171]. Another method of enzyme electrode preparation consists of enzyme immobilization on polyacryl acid modified with p-nitroaniline and by a subsequent reduction of N02-groups with titanous chloride and following diazota-tion of resulting aromatic amines [150]. An enzyme electrode has also been prepared by the direct immobilization of an enzyme on the surface of a Pt-electrode which was formerly modified first with 3-aminopropyl triethoxysilane and secondly with glutaraldehyde and bovine serum albumin [172]. Enzymes can also be immobilized on p-benzoquinone-carbon paste[173] or on the graphite electrode after its activation with cyanuric chloride [174]. In a similar way an enzyme electrode has been prepared by using iridium diiodide electrode as a support [175]. 

Immobilization Method. For the immobUization of proteins, a selection of amino, hydroxy, mercapto, and carboxy group spedfic methods should be used. For example, cyanogen bromide, tresyl, N-hydroxysucdriiriiide, epoxy, divinyl-sulfone, cyanuric chloride, and carbodiimide. The most promising method can then be further optimized. 

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