A prototype of a low-cost eyelid cleaning foaming solution for symptom management in patients with chronic blepharitis: An I-optimal mixture experimental design / Un prototipo de solución espumante de bajo costo para la limpieza de párpados y el manejo de síntomas en pacientes con blefaritis crónica: un diseño de mezcla I-óptimo

SUMMARY Blepharitis is a common chronic eye condition that causes eyelid inflammation, leading to inflamed, irritated, sticky and itchy eyelids and flaking of the skin. For its treatment, patients often need indefinite use of an eyelid cleaning solution which usually cost more than 20 USD per 80 ml bottle and lasts, on average, one month. For those patients unable to afford the treatment, physicians recommend the use of a do it yourself (DIY) solution. However, the efficacy of DIY eyelid solutions might fluctuate according to the type of blepharitis present in the patient and inadequate pH stabilization of the solution might promote additional itchiness, irritation, and dryness of the skin and eyes. Thus, we propose an optimized DIY solution prototype for symptom management in patients with chronic blepharitis. The formulation contains a significant ratio of tea tree oil and resulted in suitable pH and foam expansion values. The low cost and ease of preparation of the designed formulation make it an affordable, effective alternative in the treatment of chronic blepharitis.

RESUMEN La blefaritis crónica es una condición ocular que causa inflamación en los párpados, dando como resultado párpados irritados, pegadizos y descamación de la piel. Pacientes con esta condición necesitan usualmente de la aplicación de una solución de limpieza de párpados que cuesta en promedio 20 USD por cada 80 ml de solución y tiene un rendimiento de un mes. Para aquellos pacientes incapaces de costear el tratamiento, los médicos recomiendan el uso de soluciones hazlo tú mismo (DIY en inglés). Sin embargo, la eficacia de estas en el tratamiento de la condición puede fluctuar de acuerdo con el tipo de blefaritis presente. Adicionalmente, una inadecuada estabilización del pH de la solución puede promover una mayor irritación, resequedad y picazón en la piel y en los ojos. Por lo tanto, en este trabajo proponemos un prototipo experimental de solución DIY para el manejo sintomático de pacientes con blefaritis crónica. La formulación contiene una proporción significativa de aceite de árbol de té y posee un pH adecuado y alta producción de espuma para su correcta aplicación en la piel. El bajo costo y facilidad de preparación hacen de ella una alternativa efectiva y asequible en el tratamiento de la blefaritis crónica.

Colon targeted tablets of Albendazole with enhanced solubility by Complexation and Micellar Solubilization

Albendazole (AZ) is a drug used for the treatment of gastrointestinal nematode infections. Phase solubility study was performed to investigate the optimized ratio of AZ: β-cyclodextrin (β-CD) solid dispersion (SD). Increase in the solubility of optimized AZ: β-CD SD was further enhanced by addition sodium lauryl sulfate (SLS) in different ratios was studied. Matrix tablets of the optimized ratio of AZ: β-CD SD with SLS and various proportions (10%, 15%, and 20%) of guar gum (GG). xanthan gum (XG) and pectin (PT) were prepared by non-aqueous wet granulation with PVP K30. Standard calibration curve for AZ was performed in three buffers like 0.1 N HCl, pH 6.8 phosphate buffer solution (PBS) and pH 7.4 PBS and absorbance were measured at 295 nm. Tablets were evaluated for various physical characteristics such as thickness, hardness, and drug content uniformity. The matrix tablets were subjected to in vitro drug release studies in 0.1 N HCl (2 h), pH 6.8 PBS (3 h) and pH 7.4 PBS (19 h) with and without rat caecal content medium. Formulation F9 shows 70.65% and 95.62% of AZ in with and without rat caecal content media respectively is selected as optimized one. Optimized formulation F9 passed the test for stability up to 3 months as per ICH guidelines.

Nanopartículas de paladio soportadas en hidroxisales laminares: uso potencial en reacciones de Sonogashira / Palladium nanoparticles supported in laminar hydroxide salts: potential use in Sonogashira reactions / Nanopartículas de paládio suportadas em hidroxisais laminares: uso potencial em reacções de Sonogashira

Resumen En este artículo se reporta la síntesis de nanopartículas de paladio soportadas en hidroxisales de acetato de zinc y modificadas con un surfactante (LHS-Zn-Ac/Pd0 y LHS-Zn-Suf/Pd0 respectivamente), mediante inserción de [PdCl4]2- y su posterior reducción con etanol en reflujo. Con la inserción de surfactante, la distancia interlaminar de la hidroxisal de partida (LHS-Zn-Ac) se incrementó de 13,8 Å a 29,8 Å, mientras que los materiales finales, que contenían paladio metálico registraron distancias interlaminares de 22,4 Å y 29,4 Å para LHS-Zn-Ac/Pd0 y LHS-Zn-Suf/Pd0 respectivamente. Las hidroxisales de acetato de zinc y de surfactante con nanopartículas metálicas de paladio incorporadas fueron ensayadas como potenciales catalizadores en la reacción de Sonogashira partiendo de fenilacetileno y yoduros de arilo, particularmente yodobenceno o 2-yodofenol, dando lugar a difenilacetileno (32% de rendimiento de producto aislado y purificado) o 2-fenilbenzofurano (18%). Todos los materiales inorgánicos fueron caracterizados mediante las siguientes técnicas: difracción de rayos X (XRD), microscopia electrónica de barrido (SEM y SEM-EDS), microscopia electrónica de transmisión (TEM) y espectroscopía de Infrarrojo con Transformada de Fourier (FT-IR). Por su parte los compuestos orgánicos se caracterizaron por resonancia magnética nuclear (1H-NMR y 13C-NMR) y cromatografía de gases acoplada a espectrometría de masas (GC-MS).

Abstract This article reports the synthesis of palladium nanoparticles supported on zinc acetate hydroxysalts and modified with a surfactant (LHS-Zn-Ac/Pd0 and LHS-Zn-Suf/Pd0 respectively), by insertion of [PdCl4]2- and its subsequent reduction with ethanol at reflux. With the surfactant insertion, the interlaminar distance of the starting hydroxysalt (LHS-Zn-Ac) increased from 13.8 Å to 29.8 Å, while the final materials containing palladium metal registered interlaminar distances of 22.4 Å and 29.4 Å for LHS-Zn-Ac/Pd0 and LHS-Zn-Suf/Pd0 respectively. Zinc acetate hydroxysalt and surfactant with incorporated palladium metal nanoparticles were tested as potential catalysts in the Sonogashira reaction starting from phenylacetylene and aryl iodides, particularly iodobenzene or 2-iodophenol, giving diphenylacetylene (32% yield of isolated and purified product) or 2-phenylbenzofuran (18%). All inorganic materials were characterized by the following techniques: X-ray diffraction (XRD), scanning electron microscopy (SEM and SEM-EDS), transmission electron microscopy (TEM) and Fourier transformed infrared spectroscopy (FT-IR). The organic compounds were characterized by nuclear magnetic resonance (1H-NTMR and 13C-NMR) and gas chromatography coupled to mass spectrometry (GC-MS).

Resumo Neste artigo se reporta a síntese de nanopartículas de paládio suportadas em hidroxisais de acetato de zinco e modificadas com um surfactante (LHS-Zn-Ac/Pd0 e LHS-Zn-Suf/Pd0 respectivamente), mediante inserção de [PdCl4]2- para depois fazer uma redução com etanol em refluxo. Com a inserção do surfactante, a distância interlaminar da hidroxisal inicial (LHS-Zn-Ac) aumentou de 13,8 Å até 29,8 Å, enquanto que os materiais finais que continham paládio metálico registraram distâncias interlaminares de 22,4 Å até 29,4 Å para LHS-Zn-Ac/Pd0 e LHS-Zn-Suf/Pd0 respectivamente. As hidroxisais do acetato de zinco e do surfactante com nanopartículas metálicas de paládio incorporadas foram testados como potenciais catalisadores na reação de Sonogashira a partir de fenilacetileno e iodetos de arilo, particularmente iodobenzeno ou 2-iodofenol, levando respectivamente difenilacetileno (32% de rendimento de produto isolado e purificado) ou 2-fenilbenzofurano (18%). Todos os materiais inorgânicos foram caracterizados pelas seguintes técnicas: difração de raios X (XRD), microscopia eletrônica de varredura (SEM e SEM-EDS), Microscopia Eletrônica de Transmissão (TEM) e espectroscopia de infravermelho com transformada de Fourier (FT-IR). Por outro lado, os compostos orgânicos foram caracterizados por ressonância magnética nuclear (1H-NMR y 13C-NMR) e cromatografia gasosa acoplada à massa (GC-MS).

Optimization of Gabapentin Release and Targeting Absorption, Through Incorporation into Alginate Beads.

Aims: 1) To study the effect of some formulation variables on drug load, encapsulation efficiency, swelling ratio, mucoadhesion and drug release. 2) Optimize the mucoadhesion capabilities for targeting drug absorption and release-controlling capabilities of alginate beads. Methodology: Alginate beads were prepared by dripping sodium alginate gel into calcium chloride solution and then dried overnight at ambient temperature. The effects of alginate concentration, cross linker concentration, cross linking time, volume of cross linking solution and drug/polymer ratio on drug load, encapsulation efficiency, swelling ratio, mucoadhesion and drug release were investigated. Formulae containing sodium lauryl sulfate (SLS), gabapentin-ethylcellulose solid dispersion, mixture of free drug and solid dispersion were prepared for modifying the drug release rate. Results: Mucoadhesion of alginate beads was shown to be decreased upon adding SLS (30% after 8 hrs). Drug release was so fast (92.46% after 2 hrs). The incorporation of solid dispersion has led to well accepted mucoadhesion (74.44% after 8 hrs) as well as release properties (93.35% after 10 hrs) Beads containing mixtures of drug and ethylcellulose-drug solid dispersion showed acceptable mucoadhesion (74.44% after 8 hrs) and control of gabapentin release (93.35% after 10 hrs). Statistical analysis of variance between groups was performed using the one-way layout ANOVA with duplication. Significant differences in mean values were evaluated by Student's unpaired t test (P < 0.05). Conclusion: A finally optimized formula was suggested by incorporating a combination of solid dispersion and free gabapentin in alginate system to achieve burst release of gabapentin and hence fast effect (33.417% was released during the first 30 minutes in fasting-simulated conditions) and controlled release (91.217% after 6 hrs).

Comparative evaluation of antibacterial property and substantivity of chlorhexidine containing dentifrices with sodium lauryl sulfate and Tween as surfactants: An in vivo study.

Aim: The aim of the study was to determine the antibacterial property and substantivity of chlorhexidine containing dentifrices with sodium lauryl sulfate (SLS) and Tween as surfactants. Materials and Methods: It is a double-blind cross over the study, a total of 20 children within their mixed dentition period (7-13 year) having Streptococci mutans count more than 106 were selected for the main study. Three types of chlorhexidine containing dentifrices were used with a washout period of 1 week. Out of the three toothpastes, one was without surfactant and other two toothpastes contained SLS and Tween as surfactants respectively. 20 volunteers brushed for 1 min during the study day with their assigned toothpaste. Saliva samples were collected before brushing, immediately after brushing and 1, 3, 5, and 7 hand sent for microbial analysis. The culture carried out by inoculating saliva sample onto Mitis salivarius agar for selective isolation of S. mutans followed by counting of colony forming unit. Results: Group I and III (Chlorhexidine and CHX + Tween) had shown statistically significant reduction in bacterial count until 7 h when compared to their baseline values (P < 0.001). Group II toothpaste (CHX + SLS) had shown significant reduction in bacterial count until 3 h only. On inter group comparison, Group III had shown good amount of percentage reduction in bacterial count when compared to other groups. Conclusion: CHX + Tween toothpaste had shown statistically significant reduction in antibacterial activity and substantivity than other groups. These findings show chlorhexidine containing toothpaste with non-ionic surfactant will be able to maintain the antibacterial property and substantivity of chlorhexidine.

Glassy carbon electrode modified with multi-walled carbon nanotubes sensor for the quantification of antihistamine drug pheniramine in solubilized systems / 药物分析学报

A sensitive electroanalytical method for quantification of pheniramine in pharmaceutical formulation has been investigated on the basis of the enhanced electrochemical response at glassy carbon electrode modified with multi-walled carbon nanotubes in the presence of sodium lauryl sulfate.The experimental results suggest that the phcniramine in anionic surfactant solution exhibits electrocatalytic effect resulting in a marked enhancement of the peak current response.Peak current response is linearly dependent on the concentration of pheniramine in the range 200-1500 μg/mL with correlation coefficient 0.9987.The limit of detection is 58.31 μg/m L.The modified electrode shows good sensitivity and repeatability.

A Study on the Induction of Hardening Phenomenon by Repeated Application of Sodium Lauryl Sulfate / 대한피부과학회지

BACKGROUND: Chronic irritant contact dermatitis, the common occupational dermatitis of the skin, could be caused by repetitive exposure of the skin to irritants. Adaptation of the skin to repeated influence of exogenous irritants is called the hardening. The defining characteristic of hardening phenomenon has been progressively decreasing inflammatory response with prolonged exposure to an irritant. OBJECTIVE: The purpose of this study was to evaluate the induction of hardening phenomenon by the repeated application of various concentrated sodium lauryl sulfate (SLS) solutions. METHODS: Once a day a 0.1%, 0.5%, 2% solution of SLS and distilled water were applied to the volar forearm skin in 15 healthy volunteers for 10 minutes over 3 weeks. After 3 weeks interval of rest, patch tests with 1% solution of SLS were conducted on previously irritated sites for 24 hours. We measured transepidermal water loss (TEWL) and erythema index (E-index) before irritation, during 3 weeks of repeated application. 4 days after the patches test, we measured TEWL and E-index once a day. RESULTS: During 3 weeks of irritation with repeated application of 0.1%, 0.5%, 2% SLS solution, increase of TEWL was accelerated according to concentrations of SLS. In the study of 24-h patch test with 1% SLS solution on previously irritated sites after 3 weeks interval of rest, TEWL on distilled water application site was significantly higher than other sites irritated with SLS solution on D44 and D45. The TEWL values on the site irritated with higher concentration of SLS solution were lower than those with lower concentration of SLS solution. In contrast, there were no significant differences in E-index value during 3 weeks of irritation and after 24-h patch test with 1% SLS solution. CONCLUSION: Hardening could be induced by repeated irritation with SLS solution for 3 weeks. We suggest that hardening could be induced more efficiently with the higher concentration of SLS solution than the lower concentration.

The Skin Irritations of Corrosive and Non-corrosive Irritants in Patients with Sensitive Skin / 대한피부과학회지

BACKGROUND: Sensitive skin is largely agreed to be a lay term used by individuals who have reduced tolerance to frequent or prolonged use of cosmetics and toiletries, with symptoms ranging from subjective neurosensory forms of discomfort such as stinging, burning, itching, tightness and smarting sensations to visible signs of irritation such as erythema and scaling. Although the concept of sensitive skin is intriguing to many dermatologists, the diagnosis is dependant on self-perceived symptoms. Models to define sensitive skin are not standardized, and the term sensitive skin can be misleading. OBJECTIVE: The purpose of this study was to evaluate difference of influence to skin barrier function between corrosive and non-corrosive agents in sensitive skin. METHODS: 0.1%, 0.25%, 0.5%, 2% solution of sodium lauryl sulfate (SLS) and 1%, 2.5%, 5%, 20% solution of nonanoic acid (NAA) were applied on volar forearm skin for 24 hours in healthy controls and self-perceived sensitive skin subjects without underlying problems. Clinical score, transepidermal water loss (TEWL), and erythema-index (E-index) were compared between healthy controls and the sensitive skin group. RESULTS: Clinical scores, TEWL values and E-indices showed a rising curve concentration for each irritant in a similar pattern. There were no significant differences in clinical score and TEWL value between non-sensitive and sensitive skin. In contrast, E-indices evaluated from sensitive skin subjects were much higher than those in a healthy controls. CONCLUSION: An elevated TEWL value indicates barrier impairment. An increase in the erythema parameter shows that cutaneous vascular reactions have an unspecifically exaggerated reaction to various irritants and this induces multifarious inflammatory reactions and vasodilation. Therefore, the results of this study suggest that sensitive skin without underlying disease is derived from cutaneous vascular hyperreactivity and various inflammatory reactions, rather than barrier impairment.

Comparison of Skin Responses for Irritation Produced by Benzalkonium Chloride and Sodium Lauryl Sulfate / 대한피부과학회지

BACKGROUND: With the development of bioengineering techniques for noninvasive characterization of skin pathophysiology, the induction of irritant dermatitis by surfactants has been extensively studied. OBJECTIVE: We performed this study to compare the skin responses in terms of transepidermal water loss (TEWL) and erythema induced by benzalkonium chloride (BAC), a well-known non-corrosive irritant, in comparison with sodium lauryl sulfate (SLS), a representative corrosive irritant. METHOD: We applied 0.1, 0.2, 0.5, 1, and 2% solutions of BAC and SLS on volar forearm skin for 24 hours using a large Finn chamber with filter paper disc on 19 normal healthy subjects. TEWL and erythema index (E-index) were measured prior to testing, then at 30 minutes, one day, two days, three days, one week, and two weeks after the removal of the patches. RESULTS: TEWL values of BAC and SLS patch areas increased with concentration. However, BAC induced a significantly lower TEWL increase than SLS did at the corresponding concentrations. TEWL induced by BAC was highest at 30 minutes after the removal of the patch, whereas TEWL induced by SLS was highest at one day. TEWL values had recovered with the passage of time to baseline values at 2 weeks after removal of the patch at lower concentrations (0.1, 0.2, 0.5%) of SLS, but still showed significantly high TEWL values at 1% and 2% concentration SLS patch areas. TEWL values of BAC in 0.1, 0.2, 0.5 and 1% concentrations had recovered to the baseline values at 2 weeks after the removal of the patch, but not in 2% concentration BAC patch areas. E-indices of BAC and SLS increased with concentration in a similar reaction pattern. E-index induced by BAC was highest at 30 minutes after the removal of the patch, and E-index induced by SLS was highest at 30 minutes or 1 day after the removal of the patch. E-index of each concentration, except 2%, had recovered with the passage of time to baseline values on both BAC and SLS patch areas at 2 weeks, but E-indices of both 2% BAC and SLS did not recover at 2 weeks. CONCLUSION: Benzalkonium chloride showed much less damage to the skin barrier function compared to the corresponding concentration of SLS, whilst they showed a similar degree of erythema. Skin barrier function affected by the corrosive irritant SLS would need a more prolonged recovery time than skin barrier disruption by non-corrosive irritant BAC.

Perturbation and Recovery of the Skin Barrier Function After Tape Stripping and Sodium Lauryl Sulfate Irritation / 대한피부과학회지

BACKGROUND: The main function of the stratum corneum is to serve as a barrier preventing the penetration of irritants and transepidermal water loss (TEWL). Previous studies have shown that the cutaneous barrier disruption by application of acetone or sodium lauryl sulfate (SLS) and tape stripping leads to various metabolic changes. Recent studies showed that there was some difference in the recovery rate between tape-stripped groups and acetone-treated groups, and an individual irritant not only exerted rather specific morphologic effects on the cellular components of the keratinocyte but also induced distinct morphological alterations of the different components of the stratum corneum. In other words, this data suggested that individual irritants could show different cutaneous barrier recoveries. OBJECTIVE: This study was done to compare the recovery rate after cutaneous barrier disruption between a tape-stripped group and a SLS irritated group, and to test the relationship among baseline TEWL, TEWL after the SLS irritation, recovery of TEWL, and number of strippings needed to increase TEWL up to 20g/m2/h. METHODS: The permeability barrier of normal human skin was disrupted by tape stripping and patch of SLS and the recovery rate was assessed by measure of TEWL and erythema (E-) index. RESULTS: The number of tape strippings needed to increase TEWL up to 20g/m2/h was 32.7+-9.6 (20-50). The recovery rate of TEWL was 56.85+-17.97% twenty-four hours after tape stripping and 51.55+/-24.73% after patch removal, and 82.70+/-8.70% and 76.61+/-11.14% four days after tape stripping and patch removal. There was no significant difference in the recovery rate of TEWL after the two methods of epidermal barrier perturbation. All the correlations among baseline TEWL, TEWL after the SLS irritation, recovery of TEWL, and number of strippings were not significant statistically. E-index after the tape stripping was 12.07+/-2.95 and higher than that after removal of SLS, 11.20+/-2.51. There was irregular recovery of E-index in the SLS irritated group, but not irregular in the tape-stripped group. There was no significant difference in the recovery rate between the two groups. CONCLUSION:There was no significant difference in the recovery rates of TEWL and E-index between the tape-stripped group and the SLS irritated group. We suggest that TEWL measurements may be more desirable than the measurement of E-index in the study of perturbation and recovery of the skin barrier function.

Cutaneous Irritation to Sodium Lauryl Sulfate and Sodium Lauroyl Glutamate / 대한피부과학회지

BACKGROUND: Sodium lauryl sulfate(SLS) is the most widely utilized model for studying acute and cumulative irritation. Sodium lauroyl glutamate(SLG) has exhibited a low irritation potential and an anti-irritating effect on other anionic surfactants. OBJECTIVE: Our study was done to compare the skin irritancy of SLS and SLG using non-in- vasive techniques. METHODS: Patches with 1% SLS and SLG solution were applied to the volar forearm of 20 healthy volunteers for 24 h. Finn chambers with 8mm(20pl) and 12mm(60pl) inner diameters were used. Visual scores, transepidermal water loss(TEWL) and an erythema(E)-index were measured at 30 min after removal of the patches, and every 24hours(h) up to 4 days. RESULTS: The results are summarized as follows. 1. Visual scores were 0.20+0.30(8mm) and 0.73+0.34(12mm) at 24 h after removal of 1% SLS and were 0.15+0.29(8mm) and 0.30+0.41(12mm) at 24 h after removal of 1% SLG. They were increased at 30 min and 24 h after removal and decreased towards normal at 4 days after removal. By chamber size, the skin response with large Firin chamber(12mm) increased more significantly than with the small Finn chamber(8mm). In the small Finn chamber, there were no significant differences in the skin response between 1% SLS and 1% SLG. In the large Finn chamber, the skin response with 1% SLS increased more significantly than with 1% SLG. 2. TEWL values were 11.14+4.77(8mm) and 20.48+10.61(12mm) at 24 h after removal of 1 % SLS and were 10.38+3.99 and 14.87+7.46 at 24 h after removal of 1% SLG. They were increased at 30 min after removal and decreased towards normal 4 days after removal. By chamber size, their results were the same as the visual scores. Also, on comparison between 1% SLS and 1% SLG, their results were the same as the visual scores. 3. E-index was 10.05+2.70(8mm) and 11.15+2.56(12mm) at 24 h after removal of 1% SLS and was 10.15+2.16 and 10.60+2.26 at 24 h after removal of 1% SLG. They were increased at 30 min after removal and decreased towards normal 4 days after removal. By chamber size, their results were the same as the visual scores. In the small and large Finn chamber, there were no significant differences in the skin response between 1% SLS and 1% SLG. CONCLUSION: SLS is more irritating than SLG. The large Finn chamber may be more suitable to yield positive irritant reactions than the small Finn chamber. Also, TEWL measurements may be a more accurate and sensitive method than the E-index.

A study of skin responses produced by sodium lauryl sulfate and ethanol, and quantification of erythema using a chroma meter in healthy men / 대한피부과학회지

Irritant skin reactions can be evaluated by several techniques. Using different scores for the degree of erythema, edema, scaling and fissuring is the time-honored approach but implies t,he disadventagrs of lacking objectivity and pararretric properties. This paper describes the objective nteasurement of irritant. skin responses to various concentrations of Sodium Lauryl Sulfate(SLS) and Ethanol by a color reflectance meter(Chroma Meter) and compares with visual scoring The results are summarized as follows : 1. Pretreatment assessments by a Chroma Meter on normal forearm area showed an average score of 7.70+1.53 for Chroma Meter value a*(rediies:; score). 2. Skin responses to SLS in various concentrations of 0.5, 1.0, 2.0, 3.0, 4.0, 5.0, 7.5% under occlusion for 24 hours were assessed by visual scoring system. They are measured 0.56+1.10, 0.74+1.29, 1.19 1.36, 2.11+1.69, 2.19+1.91, 2.56+1.50 2.81+2.16 respectively. 3. Skin responses to SLS in various concentrations of 0.5, 1.0, 2.0, 3.0, 4.0, 5.0, 7.5% under occlusion for 24 hour were assessed by a Chroma Meter valu a*(redness score). They are measured 8.29+1.98, 8.37+2.47, 9.31+2.27, 10.34+2.97, 10.35+3.18, 10.51+2.47, 11.61+3.45 respectively. 4. Skin responses to Ethanol in various concentrations were nearly negligible. 5. We have demonstrated there is a highly significant correlation between skin redness measured by the Chroma Meter and visually assessed erypthma(p<0.0001). It yields reproducible, objective, quantitative measurements of iryhema that parallel the subjective visual assessments.

The Effect of pH on Sodium Lauryl Sulfate Irritancy Potential

Five volunteers received patch tests with 5% sodium lauryl sulfate (SIS) in solutions of differing pH. The irritant effect was monitored by visual scoring as well as by a laser Doppler vlelocimeter, evaporimeter, cutometer, and colorimeter. The non-invasive methods used in this study with the exception of the cutometer were effective in the evaluation of skin irritation. No significant differences in the skin responses to SIS in different pH solutions were found either clinically or by the non-invasive methods used for quantification. It was concluded that the pH of SIS is not a major factor in the degree of skin irritation produced by SIS.

Assessment of Irritancy to Sodium Lauryl Sulfate in Man by Laser Doppler Velocimetry / 대한피부과학회지

It is desirable to use more safe, objective, non-invasive method than visual scoring for the evaluation of irritation reaction and determine the optimum eoncentration of sodium lauryl sulfate(SLS) as a positive irritant control in routine patch test. In this study, SLS was applied to the volar forearm of ll non-atopic, healthy volunteers in concentrations of 0.5, 1.0, 2.0, and 5.0% under occlusion for 24h. The blood flow in test sites exposed to SLS was tecorded by laser Doppler velocimetry (LDV). The test sites were scored visually and the skin blood flow was measured at 24h, 48h, and 72h after the application of FiLS. We obtained the following results,' 1. There was a good correlation between visual scoring and skin blood flow using LDV(p = 0.4547). 2. 5.0% SLS could be used as a positive irritant control in routine patch test (p<0,05).