Sodium buffer

Fig. 6 Typical ion-exchange separation of amino acids followed by postcolumn reaction with ninhydrin. Separation was achieved employing Beckman 6300 amino acid analyzer with cation-exchange column. Three sodium buffers were used with a stepwise elution scheme as supplied/recommended by the manufacturer. Detection was the sum of 440-nm and 570-nm absorbance. Standard three-letter abbreviations for amino acids are used also, CA = cysteic acid, tau = taurine, and nle = norleucine. Data was supplied by Stephen D. Smith, Ross Products Division of Abbott Laboratories, Columbus, OH.

The origin of the sodium peak was controlled at first with a potassium barbiturate buffer which showed the same ionic distribution as the sodium buffer. Next, a sodium and a potassium barbiturate buffer were used simultaneously, each being fed in turn into one of the two electrode compartments or on the curtain itself, while the other buffer was used for the two remaining compartments (P6). The results of these experiments confirmed again the existence of a constant para-anodic concentration zone. 

Fig. 46. Ionic pattern in two-dimensional electrophoresis cascade electrodes, 6 volts/cm, Veronal-Veronalate buffer, n = 0.022 and pH 8.6, 4 hours. The background buffer flow is fed with lithium buffer, the positive cascade electrode with a sodium buffer, and the negative cascade electrode with a potassium buffer. After the run, sodium, lithium, potassium, Veronal, and conductivity are determined over the entire field. Sodium and lithium migrate toward the cathode. Potassium does not leave the cathode. The total number of cations increases from top to bottom and there is also a para-anodic zone of salt concentration. Veronal and conductivity follow the same outline ( P7).

Recent reviews by deGroot et (1), Wharmby 2) and by McVey (3) summarize the scientific and technical aspects of the high pressure sodium lamp. Thus the present report has less need to be comprehensive and will tend instead to emphasize aspects of sodium and sodium-buffer gas interactions of interest to this symposium. We shall attempt to indicate areas where basic material data are either unknown or are inadequate. 

The original method of analyses of the isopeptides in protein digests was to use ion exchange chromatography using sodium buffers (22-25). However, alternatively lithium buffers were used in order to obtain better separation and resolution ( ). More recently Griffin et al. (37) have developed HPLC to quantify G-L, whilst other workers have developed rapid ion exchange methods (3 . 3 ). 

Figure 3 Model prediction of micellar radius as a function of protein charge for a system consisting of a protein of radius 2.2 nm in 100 mM AOT isooctane - water using 0.2 M sodium buffers. (From Ref 25.)...

Mushroom tyrosinase was obtained from Sigma Chemical Co., and used without further purification. The enzyme was dissolved in 0.1 M sodium buffer, pH 7, to a concentration of 1 pg/pL, and the amount used in any given experiment depended on the amount of substrate present. Most experiments required 100-200 units of the enzyme. The enzyme solutions were prepared fresh on the day of use. The specific activity of the lot used in these experiments was 4.9 units/pg freeze-dried powder. Since the enzyme requires oxygen for activity, most experimental solutions were sparged with room air using a pasteur pipette at regular intervals during the course of the exposure. 

Buffered MEICVAICI3 melts can be made using MgCl although they are not completely buffered [142]. Magnesium metal displaces aluminum from acid melts [103,143]. While this precludes using such a melt for a magnesium battery, the reaction has been used to make buffered neutral melts from add melts [179]. This method could also be plied for lithium and sodium buffered melts. 

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