Sodium Acacia

Coa.cerva.tlon, A phenomenon associated with coUoids wherein dispersed particles separate from solution to form a second Hquid phase is termed coacervation. Gelatin solutions form coacervates with the addition of salt such as sodium sulfate [7757-82-6] especially at pH below the isoionic point. In addition, gelatin solutions coacervate with solutions of oppositely charged polymers or macromolecules such as acacia. This property is useful for microencapsulation and photographic apphcations (56—61). 

Cherry and Crandall in 1932 (86) used olive oil as substrate with gum acacia as the emufsTfier. This method has served as the basis for a number of modifications that increased the stability of the emulsion, decreased incubation time and gave better precision. When a serum sample is incubated with a stabilized olive oil emulsion, lipase acts at the interface of substrate and water to hydrolyze olive oil into fatty acid plus diglycerides, and to a small extent to monoglycerides and glycerol. The bile salt sodium deoxycholate activates the reaction. These methods measure the liberated fatty acids by titration with a standardized NaOH solution. An indicator such as phenolphatalein, thymolphthalein or methyl red or a pH meter are used to detect the end point. 

Thickeners and binders such as acacia, agar, starch, sodium alig-nate, gelatin, methyl cellulose, bentonite, and silica are used to improve product stability and enhance the convenience of the administration of a liquid formulation. Surface-active agents, colors, flavors and preservatives may also be used in the final formulation (Garcia et ah. Bioseparation Process Science, Blackwell Science, Malden, Mass., 1999, p. 374). 

Fig. 1. —Elution Pattern of Material Precipitated by Ethanol from the Mild-Acid Hydrolyzate of Acacia elata Gum. [Bio-Gel P-300, 90 x 1.5 cm column, M sodium chloride as the eluant flow rate, 3 ml/hr sample, 2 mg in 1 ml of M sodium chloride.]...

Carbomer, carmellose, microcrystalline cellulose, sodium carboxymethylcellulose, povidone, sodium alginate, tragacanth, and xanthan gum Acacia and methylcellulose, glycerol esters, polysorbates and sorbitan esters, fatty acids, sodium stearate, carbomer Macrogol esters, polyvinyl alcohol, and glycerides... 

Several of the metals yield solid hydrosols when tlieir solutions are concentrated in the presence of a protective colloid, such ns gum acacia or sodium lysalbinatc, over concentrated sulphuric neid in vacuo. On treatment with warm water the solids redissolve, yielding the colloidal solutions again. 

Sodium protalbate or lysalbate may be used instead of gum acacia.6... 

Palladium Hydrosol or Colloidal Palladium is readily prepared by the reduction of the chloride with acrolein5 or with hydrazine hydrate, in either case in the presence of an extract of Iceland moss 6 or in contact with sodium lysalbinate or protalbinate,7gum acacia,8 or with lanolin9 in a precisely similar manner to platinum,10 the function of the organic additions, which are protective colloids, being to increase the stability of the colloidal phase. 

Palladium hydrosol may be obtained in the solid condition by concentration of the aqueous solution, containing a protective colloid such as gum acacia, by exposure over sulphuric acid in vacuo It has also been prepared by passage of hydrogen through a solution of palladium chloride at 60° C. in the presence of sodium protalbate. After dialysis the solution is evaporated on the water-bath, and dried as before in vacuo over sulphuric acid. 

Osmium Hydrosol or Colloidal Osmium is readily prepared by reducing potassium osmate, K20s04, with hydrazine hydrate in the presence of some protective colloid such as gum acacia 2 or lysalbate (or protalbate) of sodium.3 The reduction may be effected with acrolein 4 if desired. 

Tablet binder Substance used to cause adhesion of powder particles in tablet granulations Acacia, alginic acid, carboxymethylcellulose sodium compressible sugar, ethylcellulose gelatin, liquid glucose, metylcellulose povidone, pregelatinized starch...

Aqueous solutions are subject to bacterial or enzymatic degradation but may be preserved by initially boiling the solution for a short time to inactivate any enzymes present microwave irradiation can also be used. Aqueous solutions may also be preserved by the addition of an antimicrobial preservative such as 0.1% w/v benzoic acid, 0.1% w/v sodium benzoate, or a mixture of 0.17% w/v methylparaben and 0.03% propylparaben. Powdered acacia should be stored in an airtight container in a cool, dry place. 

Other substances incompatible with chlorhexidine salts include viscous materials such as acacia, sodium alginate, sodium carboxymethylcellulose, starch, and tragacanth. Also incompatible are brilliant green, chloramphenicol, copper sulfate, fluorescein sodium, formaldehyde, silver nitrate, and zinc sulfate. 

Hartman AW, Nesbitt RU, Smith FM, Nuessle NO. Viscosities of acacia and sodium alginate after sterilization by cobalt-60. / Pharm Sci 1975 64 802-805. 

Polymeric thickeners Gums Acacia Alginates Carageenan Chitosan Collagen Tragacanth Xantham Celluloses Sodium carboxymethyl Hydroxyethyl Hydroxypropyl Hyd roxypro pyl m ethyl Acrylic acids Carbomers Polycarbophil Colloidal solids Silica Clays Microcrystalline cellulose Hydrogels Polyvinyl alcohol Polyvinylpyrrolidone Thermoreversible polymers Poloxamers... 

Fluoroacetate (3), the sodium salt of monofluoroacetic acid, is also a substance of vegetable origin, reported to poison sheep and cattle repeatedly. It is the toxic substance of a South African plant called gifblaar (Dichapetalum cymostm) and of the Australian plant Acacia georginae (Marais, 1944). The compound is readily soluble in water and is very toxic. Its acute oral lDj for rats is 0.2-2 mg/kg. The compound is converted via the citrate cycle into fluorocitrate and this blocks the citrate cycle. 

Concomitant use of oral zinc with tetracycline will impair antibiotic absorption. When zinc sulfate ophthalmic solution is used with sodium borate, precipitation of zinc borate may occur glycerin may prevent this interaction. Zinc sulfate ophthalmic solution has a dehydrating effect on methylcellulose suspensions, causing precipitation of methylcellulose. Zinc sulfate ophthalmic solution may also precipitate acacia and certain proteins. 

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