Container buffer

Hydrosulfite may be purchased as a proprietary formulation containing buffering and stabilizing agents, usually as a dry powder, but sometimes as a solution. The powder is pyrophoric and should be kept dry to avoid the possibiHty of fires. Alternatively, solutions of sodium hydrosulfite may be generated on-site by using a purchased solution of sodium borohydride and sodium hydroxide to reduce sulfur dioxide. 

In many patent orHterature descriptions, a stabilized chlorine dioxide solution or component is used or described. These stabilized chlorine dioxide solutions are in actuaHty a near neutral pH solution of sodium chlorite that may contain buffer salts or additives to obtain chlorite stabiHty in the pH 6—10 range. The uv spectra of these solutions is identical to that of sodium chlorite. These pH adjusted chlorite solutions can produce the active chlorine dioxide disinfectant from a number of possible organic or inorganic chemical and microbiological reactions that react, acidify, or catalyze the chlorite ion. 

The small jellyfish Phialidium gregarium (diameter 15-20 mm) used to be abundant at Friday Harbor, Washington, in summer and autumn until about 1990. Levine and Ward (1982) isolated and purified a Ca2+-sensitive photoprotein from this jellyfish and named it phialidin. They extracted the photoprotein from whole specimens with an EDTA-containing buffer. The photoprotein extract was precipitated with ammonium sulfate, and purified by the following methods gel-filtration (BioGel P-150, minus 400 mesh), anion-exchange chromatography (DEAE Bio-Gel A), and gel-filtration (Sephadex G-75, superfine). 

The ineubation of slices directly in the parent compound (PCA) did not induce 5-HT depletion, and the 5-HT innervation in these slices was indistinguishable from that in control animals. Moreover, incubation of slices from PCA-treated animals in PCA-containing buffer did not prevent the recovery of 5-HT immunoreactive axons. The absence of 5-HT depletion after immersion of hippocampal slices in PCA strongly supports the proposition that PCA and related drugs are not directly neurotoxic. Thus, in vivo systemic administration of the drug appears necessary for the formation of a neurotoxic compound, such as a metabolite of the drug or of 5-HT, which is released. 

Fluorescent labeling requires care. Unless the protein is completely labeled, which requires heroic effort, incomplete labeling converts each protein into a complex mixture of reaction products. We find that the use of FQ as the labeling reagent and the use of an SDS-containing buffer produces extremely high-efficiency separations of labeled proteins. 

Some enzymes have been found to be capable of conversion of the polyaromatic sulfur heterocycles in mixtures of an aqueous phase containing buffer+water-miscible solvent and a water-immiscible solvent. For example, conversion of thiophenes and sulfides was demonstrated in an aqueous system with 20% acetonitrile in contact with 0.2% diesel. A process for sulfur removal was designed based on this reaction [394], Additional details were given in Section 4.2.1. In a subsequent study effect of this system on PAH... 

Dissolve the protein to be thiolated at a concentration of l-5mg/ml in 50 mM sodium phosphate, pH 7.5, containing 1-10 mM EDTA. Other non-amine containing buffers such as borate, HEPES, and bicarbonate also may be used as the reaction medium. The effective pH for the NHS ester modification reaction is in the range of 7.0-9.0, but environments closer to neutrality will limit the hydrolysis of the ester. 

Dissolve the sulfhydryl-containing protein or macromolecule to be modified at a concentration of l-10mg/ml in 50mM Tris, 0.15M NaCl, 5mM EDTA, pH 8.5. EDTA is present to prevent metal-catalyzed oxidation of sulfhydryl groups. The presence of Tris, an amine-containing buffer, should not affect the efficiency of sulfhydryl modification. Not only do amines generally react slower than sulfhydryls, the amine in Tris buffer is of particularly low reactivity. If Tris does pose a problem, however, use 0.1M sodium phosphate, 0.15M NaCl, 5mM EDTA, pH 8.0. 

Prepare a series of standards, preferably consisting of serial dilutions of the substance to be measured, dissolved in water or non-amine-containing buffer. The concentration range of the standards can be anywhere between about 500ng/ml and 1 mg/ml. 

Prepare the samples dissolved in water or non-amine-containing buffer at an expected concentration level that falls within the standard curve range. The assay can tolerate the presence of most buffer salts, denaturants, and detergents. However, the standard curve should be run in the same buffer environment as the samples to obtain consistent response. 

Prepare a 5 percent cell suspension in an appropriate buffer. Avoid amine-containing buffers, as these will interact with aldehydes. 

Prepare the protein to be modified in a non-amine-containing buffer at a slightly basic pH (i.e., avoid Tris or imidazole). The use of 0.1 M sodium phosphate, 0.15M NaCl, pH 7.2 works well for NHS ester reactions. The concentration of the protein in the reaction buffer may vary from pg/ml to mg/ml, but highly dilute solutions will result in less efficient modification yields. A protein concentration from 1 to 10 mg/ml works well in this reaction. 

Dissolve the macromolecule to be modified at a concentration of l-10mg/ml in a buffered solution having a pH between 6.5 and 7.5. Avoid amine-containing buffers such as glycine and Tris. Sodium phosphate buffer at a concentration of 0.1M works well. The addition of an equal volume of a saturated solution of sodium acetate may be done to prevent tyrosine derivatization. 

Some procedures recommend the use of water as the solvent in an EDC reaction, while the pH is maintained constant by the addition of HC1. Buffered solutions are more convenient, because the pH does not have to be monitored during the course of the reaction. For acidic pH conjugations, MES [2-(N-morpholino)ethane sulfonic acid] buffer at 0.1 M works well. When doing neutral pH reactions, a phosphate buffer at 0.1 M is appropriate. Any buffers may be used that do not interfere with the reaction, but avoid amine- or carboxylate-containing buffer salts or other components in the medium that may react with the carbodiimide. 

Dissolve the amine-dendrimer to be modified in DMF or buffer (50mM sodium borate, pH 8.5) at a concentration of at least lOmg/ml. Avoid the use of amine-containing buffers for an aqueous reaction, such as Tris or imidazole, as these will react with the... 

BODIPY FL C3-SE is insoluble in aqueous solution, but may be dissolved in DMF or DMSO as a concentrated stock solution prior to addition of a small aliquot to a reaction. For aqueous reactions, a pH range of 7-9 is optimal. Avoid amine-containing buffers. The reaction also may be done in organic solvent. 

Cascade Blue diamine derivatives are soluble in aqueous solution. A concentrated stock solution may be prepared in water, dissolved quickly, and an aliquot immediately added to a buffered reaction medium. For aqueous reactions, 0.1M MES, pH 4.7-6.5, may be used to stabilize the pH during the coupling process. Avoid amine- or carboxylate-containing buffers such as Tris or glycine, since these can compete with the coupling reaction. 

The NHS ester end of NHS-LC-biotin reacts with amine groups in proteins and other molecules to form stable amide bond derivatives (Figure 11.4). Optimal reaction conditions are at a pH of 7-9, but the higher the pH the greater will be the hydrolysis rate of the ester. Avoid amine-containing buffers which will compete in the acylation reaction. NHS-LC-biotin is insoluble in aqueous reaction conditions and must be solubilized in organic solvent prior to the addition of a small quantity to a buffered reaction. Preparation of concentrated stock solutions may be done in DMF or DMSO. Nonaqueous reactions also may be done with this reagent for the modification of molecules insoluble in water. The molar ratio of NHS-LC-biotin to a... 

NHS-iminobiotin is insoluble in aqueous solution. It can be dissolved in organic solvent (DMF) prior to addition of a small aliquot to a buffered reaction medium. Don t exceed 10 percent DMF in the reaction to avoid protein precipitation problems. Optimal conditions for protein derivatization include non-amine-containing buffers at a pH of 7-9. The following... 

Dissolve the antibody to be biotinylated in 50 mM sodium bicarbonate, pH 8.5, at a concentration of 10 mg/ml. Other buffers and pH conditions between pH 7 and 9 can be used as long as no amine-containing buffers like Tris are present. Avoid also the presence of disulfide reducing agents that can cleave the disulfide group of the biotinylation reagent. 

Dissolve an antibody or protein to be modified at a concentration of l-10mg/ml in 0.1 M sodium phosphate, 0.15M NaCl, pH 1.2-1.5. Lower concentrations of protein may result in decreased reaction yields and require increased quantities of reagent to obtain acceptable levels of biotinylation. Avoid amine-containing buffers or components, such as Tris or imidazole, which will react with the NHS ester and interfere with the biotinylation process. 

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