Succinate buffer

Electroless Ni-Ge-P was studied as a model system for ternary alloy deposition [112], A chloride-free solution with GeC>2 as a source of Ge, hypophosphite as reducing agent, aspartic acid as a selective complexant for Ni2+ ions, which was operated at 80 °C in the pH range of 5-5.8, was developed for depositing Ni-Ge-P films with a tunable Ge content from 0 to 25+ at%. The use of a complexant such as citric acid, which complexed Ge(IY) ions as well as Ni2+ ions, resulted in a much lower Ge content in the electroless deposit, and a more complicated solution to study for the reasons discussed above. The aspartate-containing electroless solution, with its non-complexing pH buffer (succinic acid), approximated a modular system, and, with the exception of the aspartic acid - Ni2+ complexation reaction, exhibited a minimum level of interactions in solution. 

Polymer Labs. PLRP-S Mixture of 0.1 M KH2P04, 0.01 M citric acid and 0.01 M EDTA UV 350 nm OTC, TC, CTC, and DMC in sheep liver and cattle kidney Extraction with succinate buffer, dilution with EDTA-pentanesulphonic buffer, cleanup with C8 or XAD-2 SPE cartridge and MCAC DL = 10 pg/kg (OTC) [81]... 

Pitombo et al. [3.33] found that 0.010 M succinate buffer at pH 4.6 was the best stabilizer for SC. The influence of three different freezing rates (0.5, 1.5 and 5 °C/min) on the capability of reproduction is shown in Fig. 3.16. During 235 days storage at +25 °C, no measurable decrease in invertase activity was observed, if the RM was below 4 %. With RM approx. 14 %, the invertase activity decreased in 20 days to half and was immeasurable after 57 days, since an insoluble cluster had been formed. A 4 % RM correspond at +25 °C with a monomolecular layer of water. 

A comprehensive study of KDO 8-phosphate synthetase has been reported by Ray.137 The author purified the enzyme 450-fold from crude extracts of Escherichia coli B cells. The synthetase has a molecular mass of 90,000 6,000 daltons and is composed of three identical subunits having an apparent molecular mass of32,000 4,000 daltons. Two pH optima were observed, one being at pH 4.0-6.0 in succinate buffer, and the other, at pH 9.0 in glycine buffer. The isoelectric point of the enzyme is 5.1. The enzyme has an apparent KM for D-arabinose 5-phosphate of 20 pM and an apparent KM for enolpyruvate phosphate of 6 pM. 

Figure 4.10 Direct analysis of catecholamines in urine sample. Column, Asahipak ES-502C eluent, 75 mM succinic acid + 25 mM borate buffer (pH 6.10) containing 0.5 mM EDTA flow rate, 1.0 min-1 detection, fluorescence reaction detection Ex. 350 nm. Peaks-. 1, adrenaline-, 2, noradrenaline-, and 3, dopamine.

C. Larsen, P. Kurtzhals, M. Johansen, Kinetics of Regeneration of Metronidazole from Hemiesters of Maleic Acid, Succinic Acid and Glutaric Acid in Aqueous Buffer, Human Plasma and Pig Liver Homogenate , Int. J. Pharm. 1988, 41, 121 - 129. 

Figure 12.1 Clearance of small-molecule impurities from process buffers in a formulated protein product. Trace A the NMR spectrum of a control sample containing a mixture of three components (succinate, tetraethylammonium, and tetramethylammonium) in the final formulation buffer (sodium acetate). These three components were used in the recovery process for a biopharmaceutical product. Traces B and D the proton NMR spectra of the formulated protein product. No TEA or TMA were detected, but a small amount of succinate was observed in this sample. Traces C and E the proton NMR spectra of a formulated protein product spiked with 10 jag/ml of succinate, TEA, and TMA. Traces D and E were recorded with CPMG spin-echo method to reduce the protein signals. The reduction of NMR signals from the protein allows for better observation of the small-molecule signals.

Buffering agents— phosphate, citric, glutaric, succinic, carbonic acid... 

For incubation, cells are preincubated for five minutes at 4°C in culture medium without buffer substances and acidified with 20 mM succinic acid, pH 5.7 [Dulbecco s modified Eagle s medium (DMEM) without sodium bicarbonate, but containing 0.6% bovine serum albumin (BSA), 20 mM 2-[N-morpholino]-ethanesulfonic acid (MES), 20 mM succinic acid, pH 5.7)]. For different methods useful for acidification of cells, see Ref. (43). 

FIGURE 2 Separation of 0.2 mM dicarboxylic acids with 30 mM PDC buffer at pH 5.4 (trace A) and pH 8.2 (trace B). On trace B at 4.i min, a carbonate peak is observed. I, Malonic acid 2, succinic acid 3, giutaric acid 4, adipic acid 5, pimelic acid 6, suberic acid 7, azelaic acid 8, sebacic acid 9, dodecandioic acid. 

While Diehl et al. (2001) agree that the addition of DMSO to print buffer improves spot uniformity, they argue that DMSO is also toxic and a good solvent for other materials. As a result, they explored alternative chemistries to replace DMSO and also to improve upon postprint blocking conditions in an effort to find a replacement for borate-NMP (l-methyl-2-pyrrolidinone) buffer used for preparing solutions of succinic anhydride for capping of residual amine groups. 

The authors reasoned that the aqueous succinic anhydride capping buffer (comprised of 96% NMP and 4% sodium borate) may have led to the redissolving of probe DNA fhaf was subsequently randomly redeposited over the entire slide, leading to elevated backgrormd. As a result, a reformulation of succinic anhydride info a nonaqueous medium of dichloroet-hane (DCE) solvenf confaining N-methylimidazol (acylation catalyst) was undertaken. Significant improvements in interspot backgrounds were evident. 

The buffering ranges of a weak electrolyte are only discrete if the pA a values of its acidic and/or basic groups are separated by more than 2 pH units. Some acids have ionisable groups with pKa values less than 2 pH units apart so that they produce buffers with wide ranges. For example, succinic acid, which has pA"a values of 4.19 and 5.57, can be considered to have a continuous buffering range between pH 3.19 and 6.57. 

Succinic Anhydride— Degree of Succinylation (%) Protein Content %) Protein Solubility in Phosphate Buffer, pH 7.2 (%) Water Retention Capacity (g/g) Bulk Density (g/i)... 

Sample extraction/deproteinization is usually accomplished with mild acidic solvents to free the noncovalently bound tetracyclines from macromolecules. Mcllvaine buffer, pH 4.0 (286, 287), Mcllvaine/EDTA buffer, pH 4.0 (283, 287-293), succinate buffer, pH 4,0 (278-281,294-296), acidic acetonitrile (297-299), and acidic methanol (14, 199, 300) have all been used successfully. Moreover, trichloroacetic acid, pH 2.0 (301, 302), metaphosphoric acid (303), acetate buffer (126, 280), citrate buffer, pH 4.0 (304), citrate buffer/ethyl acetate, pH 4-5 (305), and hydrochloric acid/glycine buffer (306, 307) have all been employed with varying success to precipitate proteins from the sample homogenates. 

Succinate buffer extn, metal chelate affinity column cleanup, SPE cleanup... 

Doxycycline Turkey Succinate buffer 23 PLRP-S, 8 m. 0.01 M oxalic Fluorometric, 1 ppb/ 294... 

Mitchell used chemiosmotic to describe enzymatic reactions that involve, simultaneously a chemical reaction and a transport process. The operational definition of coupling is shown in Figure 19-18. When isolated mitochondria are suspended in a buffer containing ADP, Pi, and an oxidizable substrate such as succinate, three easily measured processes occur (1) the substrate is oxidized (succinate yields fumarate), (2) 02 is consumed, and (3) ATP is synthesized. Oxygen consumption and ATP synthesis depend on the presence of an oxidizable substrate (succinate in this case) as well as ADP and Pi. 

FIGURE 19-18 Coupling of electron transfer and ATP synthesis in mitochondria. In experiments to demonstrate coupling, mitochondria are suspended in a buffered medium and an 02 electrode monitors 02 consumption. At intervals, samples are removed and assayed for the presence of ATP. (a) Addition of ADP and P, alone results in little or no increase in either respiration (02 consumption black) or ATP synthesis (red). When succinate is added, respiration begins immediately and... 

The most widely used buffers in this category are acetate, formate, citrate, and succinate. This group is useful in the pH range 3 to 6, a region that offers few other buffer choices. All of these acids are natural metabolites, so they may interfere with the biological processes under investigation. Also, citrate and succinate may interfere by binding metal ions (Fe3+, Ca2+, Zn2+ Mg2+, etc.). Formate buffers are especially useful because they are volatile and can be removed by evaporation under reduced pressure. 

Sucrose-Tris isolation solution, 0.25 M sucrose, 0.01 MTris-Cl buffer, pH 7.8, 0.001 M succinic acid, and 0.2 mM EDTA. Keep ice-cold. Glass-Teflon homogenizer, manual or motorized Centrifuge, capable of 1200 X g and 26,000 X g... 

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