Sodium citrate 4 percent

Add to the boiling, rapidly mixing solution of chloroauric acid, 3 ml of a 1 percent sodium citrate solution. 

Note Rankings-based calculated CVs from reported mean intensity, standard deviation 1 = lowest percent CV (least variation). SSC = saline sodium citrate. DMSO = Dimethyl sulfoxide. 

Citric acid is used in soft drinks, candies, wines, desserts, jellies, jams, as an antioxidant in frozen fruits and vegetables, and as an emulsifier in cheese. As the most versatile food acidulant, citric acid accounts for about 70 percent of the total food acidulant market. It provides effervescence by combining the citric acid with a biocarbonate/carbonate source to form carbon dioxide. Citric acid and its salts are also used in blood anticoagulants to chelate calcium, block blood clotting, and buffer the blood. Citric acid is contained in various cosmetic products such as hair shampoos, rinses, lotions, creams, and toothpastes. More recently, citric acid has been used for metal cleaning, substituted for phosphate in detergents, for secondary oil recovery, and as a buffer/absorber in stack gas desulfurization. The use of sodium citrate in heavy-duty liquid laundry detergent formulations has resulted in a rapid increase in the use of citric acid. 

Figure 9-27. Buoyant densities (25°C) of native DNA s in CS2SO4 (A) and CsCl (B) gradients as a function of base composition ( , solid lines), expressed as mole percent of G + C or G + HMC, or as a function of the glucose to HMC ratio (mole %), the latter for T-even phage DNA (O, dashed lines). Denatured E. coli DNA (Den. E COLI, 0) was prepared by heating DNA (10 jag/ml) for 10 minutes at 96 to 100°C in 0.02M sodium citrate (pH = 7.8) and rapidiy chilling to 0°C. Based largely on the data of R. L. Erikson and W. Szybalski, Virology, 22 111 (1964). [From W. Szybalski, in Methods of Enzymology, Vol. 12B, Academic Press, New York, 1968, p. 330.]...

Preservatives including but not limited to the following within these maximum amounts in percent by weight of the finished food Sorbic acid, benzoic acid and their sodium, potassium, and calcium salts, individually, 0.1 percent, or in combination, 0.2 percent, expressed as the acids calcium disodium EDTA, 0.0075 percent propyl, octyl, and dodecyl gallates, BHT, BHA, ascorbyl palmitate, ascorbyl stearate, all individually or in combination, 0.02 percent stearyl citrate, 0.15 percent isopropyl citrate mixture, 0.02 percent. 

An estimate 440,000 metric tons (485,000 short tons) of potassium hydroxide were used in the United States in 2005. About 53 percent of that amount was used in the production of other potassium compounds, especially potassium carbonate (28 percent), potassium acetate, potassium cyanide, potassium permanganate, and potassium citrate. About 10 percent of all caustic potash was used in the manufacture of potassium soaps and detergents. Most soaps and detergents are made of sodium hydroxide. But potassium hydroxide can be substituted for sodium hydroxide to obtain soaps and detergents with special properties. Liquid soaps and soaps that will lather in salt water or water with a high mineral content are examples of such specialized potassium soaps. 

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