Veronal Buffers

Indirect UV absorbance detection in capillary zone electrophoresis has been used to analyze sodium alcohol sulfates. Excellent reproducibility was obtained when veronal buffer was used as UV-absorbing background electrolyte [302],... 

A new cholesterol flow injection analysis biosensor has also been described as an application of the H2O2 ECL sensor56. In that work, the luminol electrochemiluminescence, previously studied in aqueous media, was implemented in Veronal buffer added of 0.3% triton X-100 (v/v), 0.3% PEG and 0.4% cholate to enable the solubilisation of the cholesterol and then its efficient oxidation catalyzed by the immobilized cholesterol oxidase. The ECL reaction occurred thus in a micellar medium and the performances of the H2O2 ECL sensor were investigated. 

The experiments were done in Conway dishes with fraction 5 and 2.5 mM substrate in 0.1 M Veronal buffer, pH 8.4. For other details, see Messer and Ottesen (116). 

Figure 7.7 Zeta potentials (calculated from electrophoretic mobility data) relating to particles of different ionogenic character plotted as a function of pH in acetate-veronal buffer at constant ionic strength of 0.05 mol dm 3, (a) Hydrocarbon oil droplets, (b) Sulphonated polystyrene latex particles, (c) Arabic acid (carboxylated polymer) adsorbed on to oil droplets, (d) Serum albumin adsorbed on to oil droplets...

Fig. 17. Sodium (Na) and potassium (K) measured by flame photometry of eluates of strip fragments. The strip was cut transversely into sections. Buffers are either sodium or potassium Veronalate-Veronal buffers.

Fig. 23. Inhibition of evaporation. Zone electrophoresis in very small chamber with very thin walls. Field 2.7 volts/cm and 0.3 ma/cm strip Veronal buffer, pH 8. 6 r = 0.1 duration 36 hours. There is nearly linear relationship between...

To obtain well-isolated fractions the buffer needs to be a compromise between low conductivity and fair ionic strength. A Veronal-Veronalate buffer with an ionic strength of 0.033 or a Tris-Veronal buffer with an ionic strength of 0.08 is required in order to isolate clearly five fractions from normal human serum over a width of 10 to 12 cm after a 180-min run. 

Cathodic reduction of nonconjugated steroidal ketones has been found to give the equatorial alcohols with a high degree of stereoselectivity and in very good yields 134 These reactions were run at -2.6 V in aqueous ethanol-tetrabutyl-ammonium bromide. a-Methyldesoxybenzoin gave only the erythro form of 1,2-diphenylpropanol-1 on reduction at mercury in 40 % ethanol at pH 8 (veronal buffer) at -1.85 V (SCE) 13S>. 

Figure 1 shows diagrammatically the arrangement of the proteins of the serum in accordance with their mobilities, as would be found in a classical electrophoretical pattern obtained by electrophoresis of normal serum at pH 8.6 in veronal buffer. The Bence-Jones and myeloma globulins are also placed in areas where they were found in respect to the serum proteins indicated (see Table V for other data on these proteins). In each system, in both the hepatic and extrahepatic proteins (26), the ala-thr ratios change in the same direction as the... 

The mobile polar phase was an aqueous buffer (sodium acetate-Veronal buffer 1/7M at pH 7.4) alone or mixed with various quantities of acetone. The compounds were dissolved in water, acetone, or ethanol (1—3 mg/ml) and spotted in 1 jaliter amounts. The spots were detected by an alkaline solution of potassium permanganate. The penicillins could be detected also by iodine azide solution. 

Fig. 14. Electrophoretic homogeneity of porcine lipase (16). Starch columns (3.0 X 90 cm) equilibrated with 0.025 M acetate buffer, pH 5.25 (diagram on the left), or 0.025 Af veronal buffer, pH 8.0 (diagram on the right). Potential gradient inside the column, 8 volts/cm temperature, +1°C. Elution after 48 hr. Ordinates, per cent in 1 ml eluate of the total lipase activity (solid line) and total proteins (dotted line) introduced into the column. The vertical dotted line gives the true origin, with due regard to the electroosmotic flow. The figures along the peaks give the specific activity of some fractions. Specific activity of the sample introduced into the column, 3500. Abscissas, volume of eluate in milliliters.

The ch5unobypsin-catalyzed condensation of 37 (10 mM) with 38 (20 mM) was performed in 0.2 M sodium veronal buffer (pH 9) containing 40% DMSO (0.5 mL). The ch5miobypsin concentration was 1.6 X 10 M. The reaction course was monitored by isocratic reverse-phase HPLC using a C-18 column... 

Fig. 2. The dependence of nucleoside-protein conjugation on pH. A mixture of periodate-oxidized adenosine and cytidine was added to bovine y-globulin to give final concentrations of 4 mM nucleoside (0.9 mg/ml) and 6.7 ftM protein (1 mg/ml) in 0.2 M Veronal buffer titrated to varying pH. These mixtures were incubated at room temperature for 1.5 hr. Then sodium borohydride was added to a final concentration of 0.4 M (15 mg/ml), and samples were incubated for 2.5 hr at 4°. They were then dialyzed extensively against 0.1 M NaCl and analyzed for protein and nucleoside composition.

Fig. 23. Distribution of protein and protein-bound-Ii i. Paper electrophoresis Veronal buffer pH = 8.6 r/2 = 0.075. From Horowitz and Hollander (H45).

Fig. 1. A The electrophoretic pattern of gastric juice from a healthy subject in 0.1 ionic strength veronal buffer at pH 8.6 and a protein concentration of 3.9. B The same after addition of glandular mucoprotein. C The same as A after addition of mucoproteose. From Mack et al. (Ml).

Substantiating the earlier observations of Pugh et al. (P7), they also noted that nondialyzable components of gastric juice had a higher anodic mobility in phosphate buffer of pH 6.9 than in veronal buffer of pH 8.5. Four electrophoretic components labeled Gl, G2a, G2b, and G3 were resolved by this procedure (Fig. 1). Normal and duodenal ulcer juices did not differ in total number of components nor in resolution, but the... 

Various authors (D2, G24, H5-H6, N1-N3, VI, Via, W6, W7) applied to the electrophoresis of gastric juice and mucosa the standard technique used for electrophoresis of serum, i.e., horizontal unit and veronal buffer. The resolution obtained was not as good as that with serum (reviewer s comment). 

Takamura et al. and Wada et gastric juice of normal individuals and patients with histamine-fast anacidity and gastric carcinoma by continuous electrophoresis on paper curtain, and assayed the chemical composition and biological activities of the fractions obtained. Electrophoresis was performed in veronal buffer of pH 8.6 and ionic strength of 0.03, at 225 volts and 7.5-8.25 mA for 24 hours. As in paper strip electrophoresis, 4 major components were obtained, named by the authors (from anode to cathode) Bl, B2, B3, and B4 B3 contained three minor components A, B, and C. In addition, acidic gastric... 

Another very extensive study was performed by Hurlimann (H20) on 121 gastric juices, of which 32 were collected after in vivo neutralization of gastric juice by phosphate buffer of pH 8. Dialyzed and lyophilized gastric juice, collected after histamine, was subjected to microimmuno-electrophoresis at 4-8% concentration in veronal buffer for 40 minutes against horse antiserum to human serum or rabbit antiserum to gastric juice. 

Pugh et al. (P7) and Mack et al. (Mia, M2), using free boundary electrophoresis, showed that mucoprotein and mucoproteose fractions of the dissolved mucin (G5) had different electrophoretic mobilities mucoprotein fast anodic mobility (5.5-6.9 X cm sec volts ), mucoproteose slow anodic mobility (0.5-1.0 X cm sec volts ) in veronal buffer of pH 9.2 (Fig. 1). Soluble mucus had intermediate mobility of — 3.5 X 10 . It was also noted by Mack et al. (Ml) that the mucoprotein fraction processed from the acid human gastric juice, when nm by itself on Tiselius electrophoresis or when added to acid gastric juice, did not have as fast mobility as the fastest anodic component of the gastric juice, which had a mobility of 7.4-7.S X cm sec volts and which probably, as we know now, corresponded to the complex of pepsin and mucoprotein (see G5). 

Wada et al. (W7) studied mucoprotein and mucoproteose fractions by horizontal paper electrophoresis in veronal buffer of pH 8.6 and in acetate buffer of pH 4.5. They processed these materials from gastric juices of normals, patients with histamine-fast anacidity, and those with gastric cancer, which were collected after insulin stimulation. They also subjected the trichloroacetic acid precipitate of gastric juice to electrophoresis, as well as the supernatant fraction remaining after acetone precipitation of the trichloroacetic filtrate of the gastric juice. 

The mucoprotein fraction from the normal acidic gastric juice on horizontal electrophoresis had the mobility of the first anodic peak, Bl, of the gastric juice (W7). It contained very little carbohydrate. Whereas only one large band was observed in veronal buffer of pH 8.6, three small bands were detected when mucoprotein was submitted to electrophoresis... 

Schilling and Deiss first performed paper electrophoresis of gastric juice to which radioactive vitamin B12 had been added (S5). This was done by the conventional technique used for serum, in veronal buffer of pH 8.6 and 0.075 molarity at 4°C for 16 hours. After electrophoresis, papers were cut into segments, and the radioactivity of each was determined and correlated with distribution of proteins, as stained by brom-phenol blue. The main B12 binder was located on the anodic side of the partition, relatively close to the application point. In 8 experiments performed with 6 different gastric juices, the major anodic B12 binder did not coincide with any of the major protein bands in the gastric juice, but was localized between them. The technique used, however, did not permit differentiation between various B12 binders present in the gastric juice. 

Riordan (1973) has reported that the monomer of 2,3-butanedione inactivates carboxypeptidase as effectively as the trimer. One interesting feature of his study is that a 0.05 M borate buffer enhances the rate and possibly affects the distribution of products formed from both monomeric and trimeric butanedione when compared with a 0.05 M veronal buffer at the sample pH. He has attributed this specific buffer effect to the formation of a cyclic borate ester following the initial condensation of the guanidinium group with 2,3-butanedione as indicated in eq. (3.1). The conditions of modification with butanedione used by Riordan (1973) involved incubation of the protein at pH 7.5 at 20°C for 15-60 min at concentrations of butanedione ranging from 2.2 x 10 M to 7.5 X 10-2... 

---