Effect Of Sodium Lauryl Sulfate Research Articles

The transient and cumulative effect of sodium lauryl sulphate on the epidermal barrier assessed by transepidermal water loss: inter-individual variation

The aims of the investigation were: 1) to study the inter-individual variation in time course of TransEpidermal Water Loss and of clinical manifestations after a 24-h single exposure to Sodium Lauryl Sulphate. This TEWL time course (expressed as the difference in TEWL between the day of patch removal and a subsequent day) reflected the epidermal barrier response to the damage caused by SLS; 2) to investigate the association between the TEWL time course after the single SLS exposure and the TEWL value after 4-day repeated SLS exposure (as a model for cumulative irritation). The 35 healthy subjects tested could be divided into four sub-groups according to the day of their maximum TEWL value after the single SLS exposure (days 2 to 5). For the whole group, inter-individual variation in TEWL course was most pronounced in the first days following the single SLS application. Moreover, there was an inverse relationship (R = -0.61) between TEWL course during the first days after the single exposure and the TEWL value after 4-day repeated exposures. It is concluded that this association illustrates the importance of an adequately responding barrier function against the continuous exposure to irritants in daily life. The aims of the investigation were: 1) to study the inter-individual variation in time course of TransEpidermal Water Loss and of clinical manifestations after a 24-h single exposure to Sodium Lauryl Sulphate. This TEWL time course (expressed as the difference in TEWL between the day of patch removal and a subsequent day) reflected the epidermal barrier response to the damage caused by SLS; 2) to investigate the association between the TEWL time course after the single SLS exposure and the TEWL value after 4-day repeated SLS exposure (as a model for cumulative irritation). The 35 healthy subjects tested could be divided into four sub-groups according to the day of their maximum TEWL value after the single SLS exposure (days 2 to 5). For the whole group, inter-individual variation in TEWL course was most pronounced in the first days following the single SLS application. Moreover, there was an inverse relationship (R = -0.61) between TEWL course during the first days after the single exposure and the TEWL value after 4-day repeated exposures. It is concluded that this association illustrates the importance of an adequately responding barrier function against the continuous exposure to irritants in daily life. The aims of the investigation were: 1) to study the inter-individual variation in time course of TransEpidermal Water Loss and of clinical manifestations after a 24-h single exposure to Sodium Lauryl Sulphate. This TEWL time course (expressed as the difference in TEWL between the day of patch removal and a subsequent day) reflected the epidermal barrier response to the damage caused by SLS; 2) to investigate the association between the TEWL time course after the single SLS exposure and the TEWL value after 4-day repeated SLS exposure (as a model for cumulative irritation). The 35 healthy subjects tested could be divided into four sub-groups according to the day of their maximum TEWL value after the single SLS exposure (days 2 to 5). For the whole group, inter-individual variation in TEWL course was most pronounced in the first days following the single SLS application. Moreover, there was an inverse relationship (R = -0.61) between TEWL course during the first days after the single exposure and the TEWL value after 4-day repeated exposures. It is concluded that this association illustrates the importance of an adequately responding barrier function against the continuous exposure to irritants in daily life.

The reproducibility of the three broodCeriodaphnia test using the reference toxicant sodium lauryl sulfate

The three brood Ceriodaphnia dubia test was carried out three nonconsecutive times, each period being separated by the previous one by three weeks. The toxicant studied was sodium lauryl sulfate (SLS) which bacterially degrades completely by the end of the third day of the test. The mean LC50 based on survival was 41 +/- 3.2 (CV = 7.8%) mg/L for day 3 through day 6. The mean EC50 based on progeny confirmed the LC50 and was 36 +/- 0.49 (CV = 1.4%) mg/L for the ultimate day of the test. The close reproducibility among successive tests is due in part to the use of pure SLS, the use of a mixed algal diet and in part to reducing handling to a minimum. Data failed to indicate any chronic effect exhibited by C. dubia populations since no statistically significant differences were noted between 48 hr (acute) and 144 hr values (chronic). Calculations of brood size for the first four broods clearly indicate a chronic effect of SLS on C. dubia by showing a progressively greater spread between the highest mean brood size and the lowest mean brood size as the brood number increases. It is suggested that calculations of this kind become part of the Ceriodaphnia test methodology so that any chronicity can be better identified.

Effect of surfactants on the rate of mass transfer at gas-evolving electrodes

The effect of sodium lauryl sulphate surfactant on the mass transfer coefficient of the cathodic reduction of ferricyanide ion and the anode oxidation of ferrocyanide ion at hydrogen- and oxygen-evolving electrodes, respectively, was studied. Also, the effect of sodium lauryl sulphate on the gas hold-up and cell voltage was studied. The presence of surfactant in the electrolyte was found to decrease the mass transfer coefficient by an amount ranging from 7.6 to 81% depending on the operating conditions. Gas hold-up and cell voltage were found to increase in the presence of surfactant.

Effect of sodium lauryl sulphate and nickel alone and in combination on the skin of guinea pigs

Guinea pig skin was treated with 50 mg/kg sodium lauryl sulphate (SLS) and nickel (Ni) alone and in combination (50 mg/kg SLS and 50 mg/kg Ni) for 7 and 14 days. Release of acid phosphatase, alkaline phosphatase, aspartate aminotransferase, alanine aminotransferase, β-glucuronidase, lactic dehydrogenase and malic dehydrogenase was observed, following treatment with SLS and Ni alone or in combination. Similarly, the skin contents of amino nitrogen and sulphydryl groups also increased significantly. These alterations were slightly more marked when the skin was treated simultaneously with the combination of SLS and Ni. The present study suggests that industrial workers or populations exposed simultaneously to SLS and Ni are more prone to dermal irritation or inflammation.

Effect of sodium lauryl sulfate on the deposition of alkali-soluble fluoride on enamel in vitro.

There are indications that sodium lauryl sulfate may reduce the cariostatic effect of fluoride when present together with sodium monofluorophosphate during topical application. The aim of the present study was to examine the in vitro deposition of alkali soluble fluoride on enamel during topical application with sodium fluoride in combination with sodium lauryl sulfate. It was found that increasing amounts of lauryl sulfate decreased the amount of alkali soluble fluoride deposited on the enamel. The amount of fluoride deposited from toothpaste supernatants was less than that from aqueous solutions of NaF with the same concentration of fluoride. Enamel pieces, pretreated with sodium lauryl sulfate showed a reduced deposition of alkali-soluble fluoride after incubation in a fluoride solution. It was also observed that the presence of lauryl sulfate increased the solubility of CaF2 in water.

Acute toxicity of synthetic detergents to snails: effect of sodium lauryl sulfate on Limnaea peregra shells.

Acute toxicity of synthetic detergents to snails: effect of sodium lauryl sulfate on Limnaea peregra shells.

Effect of sodium lauryl sulphate on rat liver and kidney enzymes: an in vitro study.

Effect of sodium lauryl sulphate on rat liver and kidney enzymes: an in vitro study.

In vitro effects of sodium lauryl sulfate on DNA synthesis and fine structure of human thymocytes.

Sodium lauryl sulfate, a model substance in testing skin irritability was examined with regard to its effects on DNA synthesis and fine structure of human thymocytes incubated in vitro. At 5 h, incorporation of 3H-thymidine into DNA was inhibited with a discernable effect at 3 X 10(-4) M in serum-free medium and at 6 X 10(-4) M in medium to containing 15% serum. Under the former conditions, the effect on DNA synthesis was accompanied by disintegration of the cells as observed electron-microscopically. In contrast, no clear effects on cell morphology were seen in the latter case, in spite of a strongly depressed replicative activity. After 48 h of culture in medium containing 15% serum, there was a marked decrease in cell number due to spontaneous cell death and, consequently, a low rate of DNA synthesis. Sodium lauryl sulfate suppressed the incorporation of 3H-thymidine into DNA at 1.2 X 10(-3) M. No clear alterations in cell morphology were observed at 3 X 10(-4) M, whereas signs of irreversible cell damage, including pyknotic nuclei, were seen at 6 X 10(-4) M and complete disruption of most cells occurred at 1.2 X 10(-3) M. The results show that sodium lauryl sulfate inhibits DNA synthesis in human thymocytes and that there is a partial discrepancy between this inhibition and the adverse effects on the structural organization of the cell. It is proposed that the irritant effect of sodium lauryl sulfate in vivo is due to the breaking up of lymphoid or other cells and a consequent release of material that gives rise to an inflammatory response.

The effect of surfactants on the microencapsulation and release of phenobarbitone from gelatin-acacia complex coacervate microcapsules.

The effects of sodium lauryl sulphate (SLS), cetrimide and polysorbate 20 surfactants at concentrations below, at and above their critical micelle concentration (CMC) on the microencapsulation and release of phenobarbitone have been described. Bimodal particle size distributions were produced both in the absence and presence of each of the three surfactants. The presence of surfactant had little or no effect on the particle size distribution at any given stirring speed. A large variation was noted in the amount of phenobarbitone microencapsulated dependent upon the type of surfactant and its concentration. The amount of phenobarbitone encapsulated decreased with increasing concentration of polysorbate 20 and with SLS. Cetrimide (0.025 per cent w/v) enhanced encapsulation with 2 per cent w/w colloids but higher concentrations at the CMC and above decreased encapsulation. The results are explained in terms of decreased interfacial tension by the surfactant and by steric and electrostatic effects caused by surfactant adsorption onto the coacervate droplets and phenobarbitone particles.

Effect of Sodium Lauryl Sulphate and TweenR80 on the Therapeutic Efficacy of Glibenclamide Tablet Formulations in Terms of BSL Lowering in Rabbits and Diabetic Human Volunteers

Glibenclamide has limited gastrointestinal absorption. Therefore, different concentrations of sodium lauryl sulphate and tweenR80 were included into the tablet formulations to increase the absorption of the drug and hence, to enhance the BSL lowering in rabbits and human volunteers suffering from maturity onset diabetes mellitus. It was found that the surfactants had enhanced both the rate and extent of BSL lowering in rabbits as well as in diabetic patients in higher concentrations present in the tablet formulations.

The Effect of Sodium Lauryl Sulphate on Topical Drug Availability

The Effect of Sodium Lauryl Sulphate on Topical Drug Availability

The effect of sodium lauryl sulphate, cetrimide and polysorbate 20 surfactants on complex coacervate volume and droplet size.

The effects of sodium lauryl sulphate (SLS), cetrimide and polysorbate 20 surfactants at concentrations below, at and above their critical micelle concentration (CMC) on the complex coacervation of varying concentrations of gelatin and acacia have been described. The overall effect of increasing concentration of SLS was to reduce the weight of coacervate formed. The addition of increasing concentrations of cetrimide produced an increase in the weight of coacervate. The two lowest concentrations of polysorbate 20 produced an increase in coacervate weight while the highest concentration, above the CMC, reduced the coacervate weight. These effects have been explained in terms of shielding of electrostatic attractions between gelatin and acacia polyions by adsorption of ionic and non-ionic surfactant molecules onto the polyions. The addition of surfactants influenced the size distribution of the coacervate droplets that were produced. It is believed that the reduction in interfacial tension by the aggregation of surfactant molecules at the coacervate-equilibrium liquid interface permitted the formation of smaller coacervate droplets.

Skin protection against ionized cobalt and sodium lauryl sulphate with barrier creams.

853 individuals who are still working or had previously worked in hard metal manufacture were examined and selected for patch tests with materials from their working environment including metal allergens. The majority of the individuals with positive test reactions to cobalt chloride were retested with serial dilutions of cobalt chloride and with the same serial dilutions after preparation of the skin with a layer of barrier or emollient cream used for hand care in this factory. The irritant effect of sodium lauryl sulphate (SLS) was similarly investigated. The barrier and emollient creams did not give any protection against cobalt chloride or sodium lauryl sulphate. In fact they seemed to enhance the penetration of cobalt ions. Their use in protection against metal allergens and cutting fluids is questionable.

Effect of sodium lauryl sulfate on the polymerization of acrylonitrile

AbstractMicellar catalyzed polymerization of acrylonitrile using ceric(IV)–glycerol redox system in aqueous sulfuric acid solution in the presence of sodium lauryl sulfate (NaLS) has been studied. The polymerization experiments were conducted between 15°C and 25°C, under conditions where no oxidation of sodium lauryl sulfate by ceric ion would we expected. The rate of polymerization (Rp) increases with increasing concentration of NaLS. The rate of monomer (AN) disappearance was proportional to [AN]1.5 and [glycerol]0.5, but, however, Rp changes in a nonlinear manner with increase in Ce(IV) concentration in the presence of the surfactant. The rate of Ce(IV) disappearance was not proportional to its original concentration. The chain length of the polymer could not be determined viscometrically, as the polymer obtained in presence of NaLS was insoluble in organic solvents. The activation energy of this polymerization process was calculated by conducting the experiment at different temperatures. The infrared spectra of the polymers in the presence and absence of surfactant have also been examined.

Effects of sodium lauryl sulfate on glucan synthesis by glucosyltransferases of Streptococcus mutans OMZ 176

Effects of sodium lauryl sulfate on glucan synthesis by glucosyltransferases of Streptococcus mutans OMZ 176

Effect of swascol ® 1P (SLS) on liver, kidney and intestine acid and alkaline phosphatases from Channa punctatus and Cirrhina mrigala

Liver, kidney and intestine homogenate acid and alkaline phosphatases from Channa punctatus exposed to sodium lauryl sulphate (SLS) in vitro were markedly affected. Maximum inhibition was also noted on liver alkaline phosphatase activity from Cirrhina mrigala. Alkaline phosphatase activity in liver and kidney was more inhibited than acid phosphatase. Acid phosphatase inhibition in intestine was more pronounced than that of alkaline phosphatase. The effect of SLS on these phosphatases was concentration dependent and varied from tissue to tissue and from fish to fish.

In vitro effect of sodium lauryl sulphate on ATPase system in a few tissues from Channa punctatus

In vitro administration to sodium lauryl sulphate (SLS) of a few tissues from Channa punctatus have a remarkable effect on the ATPase system. Maximum inhibition was noted in the brain followed by gill, kidney and liver, respectively. Inhibition of oligomycin-insensitive Mg 2+ ATPase activity was more significant as compared to that of Na +-K + and oligomycin-sensitive Mg 2+ ATPase activities. It is inferred that the effect of SLS on the ATPase system is concentration-dependent and varying from tissue to tissue.

The Influence of Anionic Surfactant on the Stability of Styrene — Acrylonitrile Copolymer Latices

AbstractStyrene — acrylonitrile copolymer latices were prepared by emulsion polymerisation using sodium lauryl sulphate as emulsifier and potassium persulphate as initiator. The effect of sodium lauryl sulphate on the stability of these copolymer latices has been investigated using magnesium chloride as flocculating agent by measuring the rates of flocculation in the presence of various concentrations of surfactant. The values of the critical coagulation concentration (ccc) were found to increase with increasing sufactant concentration for all latices.The rates of increase in ccc with increasing surfactant concentrations were found to be almost independent of the content of acrylonitrile in the latex particles. The electrophoretic behaviour of these latices in the presence of the ionic surfactant has also been studied. The values of mobilities at ccc were found to decrease slightly with increase in the concentration of the ionic surfactant.

Toxic action of several lethal concentrations of an anionic detergent on the gills of the brown trout (Salmo trutta L.)

The pathological effects often lethal concentrations of the anionic detergent, sodium lauryl sulphate, on the gills of Salmo trutta L. have been studied by light and electron microscopy. At concentrations to 120 mg/1 (medium survival times >1 h), epithelial cell death is associated with lysosome formation. Acute inflammation of the gill tissue, extensive detachment of the epithelium and, except at the lowest concentrations, collapse of the pillar cell system occur. At concentrations above 120 mg/1 (medium survival times <1 h) very rapid lysis of cells results in the complete disruption of cellular and tissue structure. Changes in the gross structure of the gills are explainable in terms of the rate and nature of toxic action at the cellular level. Review of the biomedical literature suggests the observed effects of sodium lauryl sulphate on gill cells correspond to the two mechanisms by which detergents cause death in isolated cells. These are autolysis, i.e. lysis by the action of the cell's own enzymes, induced by an initial lesion in the cell membrane whose precise nature is not known; and rapid lysis by the direct action of the detergent on the cell constituents.

Increased intestinal absorption in the rat caused by sodium lauryl sulphate, and its possible relation to the cAMP system

The increases in the absorption of ouabain, phenolsulphonphthalein and pralidoxime caused by 17 mM sodium lauryl sulphate (SLS) from jejunal loops of anaesthetized rats were significantly reduced if sodium and chloride (Briseid et al., 1974) or chloride and bicarbonate were replaced by other ions in the loop fluid. Separate substitutions of sodium, chloride of bicarbonate did not significantly alter the SLS-caused absorption, except that the substitution of choline for sodium reduced the absorption of pralidoxime, both in the presence and in the absence of SLS. The increases in the absorption of phenolsulphonphthalein and pralidoxime caused by SLS were potentiated by theophylline (25 mM) and reduced by imidazole (25 mM). The addition of dibutyryl cyclic AMP (2.5 mM) to the loop fluid increased this absorption of the test substances. This effect was reduced by imidazole, but under the experimental conditions it was not potentiated by theophylline. Determinations of cyclic AMP in the rat intestinal mucosa showed that the level of this substance was significantly higher in the presence than in the absence of SLS. The experimental conditions were as described for the absorption experiments. It is concluded that the data obtained support the idea of an increased level of cyclic AMP as the main basis for the effect of SLS on the absorption.