Alkaline Borate Buffer

Algin, 24, 54,312, 351 Alginates Assay, 768 Algin Derivative, 331 AlginicAcid, 19 Alkaline Borate Buffer, 848 Alkaline Cupric Citrate TS, 851 Alkaline Cupric Tartrate TS, 849 Alkaline Mercuric-Potassium Iodide TS, 850... 

Fig. 19. Reductive amination for separation of carbohydrate derivatives in an alkaline borate buffer by capillary electrophoresis.

Introductory conditions for initial MEKC separations of neutral or weakly ionizable analytes are provided in Table 3.1 [4]. The choice of the running solution is rather arbitrary, but a weakly alkaline borate buffer is recommended because the electrophoretic mobility of the borate ion is rather low and, thus, the current can be kept low. The sample solution can be prepared in any solvents provided... 

Lanz et al. [185] compared two different methods in fused-silica capillaries with alkaline borate buffers and different dynamic coatings (DAB and spermine, respectively) and with the doublecoating method based on commercially available buffers. The latter method provided faster and more reproducible results. In addition, Tf isoforms peaks were more intense when analyzed with the latter method. 

Die methodology of alkaline, borate buffered persulphate oxidation (Korolejf, 1977), is also applicable to the decomposition of suspended sUicon.Die procedure given here is similar to that for total phosphorus (see Section 10.2.14), i.e., the sample is autoclaved with per-oxodisulphate at pH 9.7 in the beginning and at about 5 at the end of the oxidation. Silicate is then determined according to Section 10.2.11. 

A detailed investigation of the nature of the thermal decomposition of 2-deoxy-2-(2,4-dinitroanilino)-D-glucose in alkaline borate buffer has been reported. However, the reason why this amino-sugar derivative, but not the isomeric 2-deoxy-2-(2,4-dinitroaniIino)-D-galactose, is degraded remains somewhat elusive, although a 3,5-borate complex seems to be involved in the degradation. 

On Cu, it was also shown that the anodic dissolution, in a mildly alkaline borate buffer solution, is catalyzed by a submonolayer of sulfur and that S remains adsorbed on the copper surface [10]. 

A very sensitive and specific postcolumn derivatization reagent is OPA. OPA reacts with primary amines in the presence of a reducing reagent such as 2-mercaptoetha-nol, producing a fluorescent substance with an excitation wavelength of 340 nm and an emission wavelength of 455 nm. The reaction occurs in an alkaline borate buffer in the range of pH 9 to 11. The most commonly used form of borate is the potassium salt however, the sodium salt has also been used. 

Benzoate can be used as an anodic inhibitor and is effective at preventing waterline attack. Phosphate is also sometimes included. Sodium borate (borax) is usually added to the formulation to provide an alkalinity reserve buffer. Typically, a copper inhibitor such as benzo-triazole (BTA) or tolyltriazole (TTA) also forms part of a formulation and is used to provide yellow metal (copper and brasses) protection. 

Borate is usually added to nitrite-based formulations to provide an alkalinity reserve buffer, ensuring that the system water pH level is maintained within the range of 7.5 to 9.5 (or greater). 

Another approach for the synthesis of enantiopure amino acids or amino alcohols is the enantioselective enzyme-catalyzed hydrolysis of hydantoins. As discussed above, hydantoins are very easily racemized in weak alkaline solutions via keto enol tautomerism. Sugai et al. have reported the DKR of the hydantoin prepared from DL-phenylalanine. DKR took place smoothly by the use of D-hydantoinase at a pH of 9 employing a borate buffer (Figure 4.17) [42]. 

Reduction of NilvL2+ in aqueous media by two-electron reductants such as 1,2- or 1,4-dihydroxybenzene proceeds by consecutive two-electron transfer with formation of nickel(II) intermediates.3124,3125 Nickel(III) complexes with (415) and (416) of formula Nim(HL)(C104)2 and Nim(HT)(C104)2 have been obtained by oxidation with (NIL Og in borate buffer and alkaline solution respectively of nickel(II) complexes or by exposure of the nickel(IV) complexes to moist air.3031 The g values of the nickel(III) species are gii = 2.03-2.05, g = 2.15-2.16.3039,3104... 

Irreversible inactivation of Ta bacteriophage also occurred when the phage was incubated with periodate-oxidized polyglucose 11 at pH 8.5-10.0 in the presence of 0.1 M borate buffer. Interpretation of the data is difficult, in view of the known lability and modification of polysaccharide polyaldehydes in alkaline media, 14 especially since phage inactivation occurs only at elevated pH values in the presence of polyaldehyde and 0.1 M borate buffer. 

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