Sodium caprylate

Inactivation and Removal of Viruses. In developing methods of plasma fractionation, the possibiHty of transmitting infection from human vimses present in the starting plasma pool has been recognized (4,5). Consequentiy, studies of product stabiHty encompass investigation of heat treatment of products in both solution (100) and dried (101) states to estabHsh vimcidal procedures that could be appHed to the final product. Salts of fatty acid anions, such as sodium caprylate [1984-06-17, and the acetyl derivative of the amino acid tryptophan, sodium acetyl-tryptophanate [87-32-17, are capable of stabilizing albumin solutions to 60°C for 10 hours (100) this procedure prevents the transmission of viral hepatitis (102,103). The degree of protein stabilization obtained (104) and the safety of the product in clinical practice have been confirmed (105,106). The procedure has also been shown to inactivate the human immunodeficiency vims (HIV) (107). 

HSA is used therapeutically as an aqueous solution it is available in concentrated form (15-25 per cent protein) or as an isotonic solution (4-5 per cent protein). In both cases, in excess of 95 per cent of the protein present is albumin. It can be prepared by fractionation from normal plasma or serum, or purified from placentas. The source material must first be screened for the presence of indicator pathogens. After purification, a suitable stabilizer (often sodium caprylate) is added, but no preservative. The solution is then sterilized by filtration and aseptically filled into final sterile containers. The relative heat stability of HSA allows a measure of subsequent heat treatment, which further reduces the risk of accidental transmission of viable pathogens (particularly viruses). This treatment normally entails heating the product to 60 °C for 10 h. It is then normally incubated at 30-32 °C for a further 14 days and subsequently examined for any signs of microbial growth. 

Fatty acids (e.g., sodium caprate, sodium caprylate, sodium laurate, and sodium oleate)... 

Contrary to carbon enterosorbents, Enterosgel does not possess an ability for selective removal of albumin-bound ligands regardless of their affinity with the protein carrier - weak (L-tryptophane), medium (sodium caprylate, deoxycholic acid), or strong (indole-3-carboxylic acid and unconjugated bilirubin). It means that if protein-bound toxins are removed by Enterosgel, this occurs simultaneously with adsorption of the carrier protein. 

Ligand M /Mp L-Tryptophan 104 Da Sodium caprylate 166 Da Deoxycholic acid 392 Da Indole-3-carboxyUc acid 161 Da Unconjugated bihrubin 584 Da... 

Fig. 29.12 HSGD coating with HSA conformer (=13 moles of sodium caprylate per 1 mole HSA) does not affect the kinetics of unconjugated bilirubin adsorption...

The phase diagram shown in Figure 8.7 is simpler than many other ternary phase diagrams inasmuch as only one liquid crystal phase exists, and there are no three-phase triangles. By contrast, the water-decanol-sodium-caprylate phase diagram at 20°C shows 5 different liquid crystal phases and 10 triangular regions, in each of which 3 different sets of phases are in equilibrium. 

Laser-Raman spectroscopy is a new method with considerable potential for providing an explanation of how the surroundings inside the aggregates influence the crystalline state of the hydrocarbon chains and other groups (25, 26). It seems probable, however, that an important area of research on the phase equilibria proper would concentrate on attempts to throw light on the exact thremodynamic criteria for the association processes. Ekwalls studies of the water activities of mesophases in the system water-decanol-sodium caprylate are an example of such research (4). However, thermodynamic treatment of the association processes presupposes measurements of the activities of several... 

Solyom and Ekwall (20) have studied rheology of the various pure liquid crystalline phases in the sodium caprylate-decanol-water system at 20 °C, for which a detailed phase diagram is available. Their experiments using a cone-and-plate viscometer show that, in general, apparent viscosity decreases with increasing shear rate (pseudo-plastic behavior). Values of apparent viscosity were a few poise for the lamellar phase (platelike micelles alternating with thin water layers), 10-20 poise for the reverse hexagonal phase (parallel cylindrical micelles with polar... 

Matsumoto, Y., et al. 1989. Rectal absorption enhancement of gentamicin in rabbits from hollow type suppositories by sodium salicylate or sodium caprylate. Drug Des Deliv 4 247. 

Experiments have confirmed the idea that micelles as well as vesicles could grow autocatalytically (see [41] for a good overview). In a landmark paper Bachmann et al. [42] observed the formation of autocatalytically replicating micelles from sodium caprylate. The micelles could be converted into more stable vesiscles by pH change. Oleic acid/oleate vesicles can also mul-... 

Luisi has shown that membrane material itself can be formed autocatalytically in an experiment to investigate the base catalysed ester hydrolysis of hydrophobic ethylcaprylate [27], Hydrolysis occured initially at the aqueous-organic interface where the products were micelle-forming sodium caprylate and ethanol. Once the critical micelle concentration, or cmc, was reached an exponential increase in hydrolysis was observed. The rate of hydrolysis in this second phase was almost 1000 times greater than in the initial phase suggesting that a catalytic mechanism had been activated. Luisi and co-workers hypothesized that once the cmc had been reached hydrolysis occurred within the micelles and, as the reactants were then constrained within a more hydrophobic environment, the increased rate was due to autocatalysis. Below pH 7 the micelles reorganized into unstable vesicles, in the order of 150 nm across as verified by freeze-fracture electron microscopy. 

Small solutes such as urea and sodium caprylate often coexist with protein macromolecules in solutions. When these small molecules diffuse the protein solution, the diffusivity of the molecules decreases with increasing protein... 

Sawada, T. Ogawa, T. Tomita, M. Hayashi, M. Awazu, S. Role of paracellular pathway in non-electrolyte permeations across rat colon epithelium enhanced by sodium caprate and sodium caprylate. Pharm. Res. 1991, 8, 1365-1371. 

Sodium caprylate (sodium octoate) has antifungal properties, but it is also used to improve the stability of albumin solution against the effects of heat. Albumin solution can be pasteurized by heating at 60°C for 10 h in the presence of sodium caprylate. Acetyl tryptophanate sodium is also added to albumin formulations. 

Fatty acids and derivatives Sodium caprylate Sodium caprate Sodium laurate Oleic acid Monoolein Increase membrane fluidity by Creating disorder in phospholipid domain of the membrane Eacilitating the leaching of proteins from the membrane... 

The data discussed here are for Plasbumin -25, which is purified from Fraction V paste and consists of 23.5 /o-26.5 /o protein, of which no less than 96.5%o is albumin. The preparation is stabilized with 0.02 M sodium caprylate and 0.02 M acetyltryptophan and contains 145mEq/L sodium. For the virus clearance experiments, virus was spiked into albumin, pH 6.4-7.4, and the solution was heated at 60°C for 10 hr. Aliquots for virus titration were removed as soon as virus was added (preheat), when the temperature of the solution reached 60° C (Ohr) and at various times during the pasteurization cycle. Unheated albumin and HBSS were also spiked to the same dilution with virus and tested as positive controls. 

The USP 28 describes albumin human as a sterile nonpyrogenic preparation of serum albumin obtained from healthy human donors see Section 13. It is available as a solution containing 4, 5,20, or 25 g of serum albumin in 100 mL of solution, with not less than 96% of the total protein content as albumin. The solution contains no added antimicrobial preservative but may contain sodium acetyltryptophanate with or without sodium caprylate as a stablizing agent. 

The PhEur 2005 similarly describes albumin solution as an aqueous solution of protein obtained from human plasma see Section 13. It is available as a concentrated solution containing 150-250 g/L of total protein or as an isotonic solution containing 35-50 g/L of total protein. Not less than 95% of the total protein content is albumin. A suitable stabilizer against the effects of heat, such as sodium caprylate (sodium octanoate) or N-acetyltryptophan or a combination of these two at a suitable concentration, may be added, but no antimicrobial preservative is added. 

Several other pyrolytic studies were performed on nylon 6. In one such study [4], the influence of several aliphatic carboxylates on nylon 6 thermal degradation was studied. The carboxylates that were evaluated include sodium butyrate, sodium caproate, sodium a-ethylcaproate, sodium caprylate, sodium laurate, potassium caproate, potassium laurate, and lithium caproate. Small amounts of these aliphatic carboxylates strongly increase the thermal decomposition rate even at 280° C. The effect of aliphatic carboxylates can be explained by the deprotonation of one of the amide groups of the polymer followed by the nucleophilic substitution of a neighboring carbonyl group, in a reaction as shown below ... 

Sodium caprylate is used topically to treat superficial der-matomycoses caused by C. albicans and Trichophyton. Mi-crosporum. and Epidemutphyton spp. The sodium salt can be purchased in solution, powder, and ointment forms. 

Sodfum Caprylate. Sodium caprylate is prepared from opiylic acid, which is a component of coconut and palm lUls The salt precipitates as cream-colored granules that are 4iluble in water and sparingly soluble in alcohol. 

Figure 6 The experiment of Luisi and coworkers with ethyl caprylate leading to micelles of sodium caprylate by hydrolysis. Because of the continuous supply of ethyl caprylate, the micellar system self-replicates...

Fatty acids (sodium caprylate, laurate, caprate, oleic acid, monoolein)... 

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