In-Vitro and Ex-Vivo Evaluation of Transfersomal Gel of Methotrexate

Abstract Methotrexate on its oral and intravenous administration results in unwanted adverse effects. This drawback can be overcome by transdermal delivery because of its painless objective for systemic drug administration. Transfersomes are ultra-deformable vesicles with the flexibility to reach deeper tissues of the skin. The objective of this research work was to develop methotrexate transfersomal gel by thin film hydration technique, evaluated for entrapment efficiency, deformability, mean vesicle size, and stability, and incorporated into carbopol gel for ease of handling and skin applicability for a longer period of retention on skin. MTX-TFS gel & conventional gel were characterized for consistency, transparency, viscosity, and pH. Ex-vivo skin permeation studies were performed using abdominal goat skin and drug release kinetic parameters and transdermal flux were calculated using mathematical models. The results indicate that MTX was successfully entrapped (84.77 ± 2.35 %w/w) in transfersomes having 240±1.6 nm vesicle sizes and 27.13±0.7 deformability index. The gel was permeated through the skin at a rate of 28.12±2.58 µg/cm2/hr as compared to the conventional gel (10.35±2.14 µg/cm2/ hr). From the study, it was concluded that the MTX-TFS gel can be used as a possible substitute for the conventional formulation for transdermal drug delivery due to 3 times improvement in transdermal flux.

Locust bean gum hydrogels are bioadhesive and improve indole-3-carbinol cutaneous permeation: influence of the polysaccharide concentration

Abstract The locust bean gum (LBG) is a polysaccharide with thickening, stabilizing and gelling properties and it has been used in the preparation of pharmaceutical formulations. Hydrogels (HGs) are obtained from natural or synthetic materials that present interesting properties for skin application. This study aimed to develop HGs from LBG using indole-3-carbinol (I3C) as an asset model for cutaneous application. HGs were prepared by dispersing LBG (2%, 3% and 4% w/v) directly in cold water. The formulations showed content close to 0.5 mg/g (HPLC) and pH ranging from 7.25 to 7.41 (potentiometry). The spreadability factor (parallel plate method) was inversely proportional to LBG concentration. The rheological evaluation (rotational viscometer) demonstrated a non-Newtonian pseudoplastic flow behavior (Ostwald De Weale model), which is interesting for cutaneous application. The HET-CAM evaluation showed the non-irritating characteristic of the formulations. The bioadhesive potential demonstrated bioadhesion in a concentration-dependent manner. Permeation in human skin using Franz cells showed that the highest LBG concentration improved the skin distribution profile with greater I3C amounts in the viable skin layers. The present study demonstrated the feasibility of preparing HGs with LBG and the formulation with the highest polymer concentration was the most promising to transport active ingredients through the skin.

Analysis of docosanol using GC/MS:Method development,validation,and application to ex vivo human skin permeation studies / 药物分析学报

Docosanol is the only US Food and Drug Administration(FDA)approved over-the-counter topical product for treating recurrent oral-facial herpes simplex labialis.Validated analytical methods for docosanol are required to demonstrate the bioequivalence of docosanol topical products.A gas chromatography/selected ion monitoring mode mass spectrometry(GC/SIM-MS)method was developed and validated for docosanol determination in biological samples.Docosanol and isopropyl palmitate(internal standard)were separated on a high-polarity GC capillary column with(88％cyanopropy)aryl-polysiloxane employed as the stationary phase.The ions of m/z 83 and 256 were selected to monitor docosanol and isopropyl palmitate,respectively;the total run time was 20 min.The GC/SIM-MS method was validated in accordance with US FDA guidelines,and the results met the US FDA acceptance criteria.The docosanol calibration standards were linear in the 100-10000 ng/mL concentration range(R2＞0.994).The recoveries for docosanol from the receptor fluid and skin homogenates were＞93.2％and＞95.8％,respectively.The validated method was successfully applied to analyze ex vivo human cadaver skin permeation samples.On applying Abreva?cream tube and Abreva?cream pump,the amount of doco-sanol that penetrated human cadaver skin at 48 h was 21.5±7.01 and 24.0±6.95 ng/mg,respectively.Accordingly,we concluded that the validated GC/SIM-MS was sensitive,specific,and suitable for quantifying docosanol as a quality control tool.This method can be used for routine analysis as a cost-effective alternative to other techniques.

In vitro skin retention and drug permeation study of Tongluo-Qutong rubber plaster by UPLC/UV/MS/MS

Abstract Tongluo-Qutong rubber plaster (TQRP), a typical Chinese patent medicine that contains 13 different herbal remedies, is widely used in clinical practice for the treatment of cervical spondylosis and osteoarthritis. However, due to a lack of in vitro transdermal studies, the active ingredients of TQRP have not been fully elucidated. This presents a huge obstacle for quality evaluation, pharmacokinetic studies and clinical safety assessment of TQRP. In this work, a UPLC/UV/MS/MS method was established and validated to evaluate five analytes in TQRP. The validation demonstrated linearity (r > 0.99), specificity (no co-eluting peaks at the retention times of the analytes), and precision (RSD < 15%) within acceptable parameters. A skin permeation study was performed to determine the concentrations of drugs delivered to the dermis. The 24-hour cumulative permeation of ferulic acid, aleo-emodin, emodin and piperine were 303.68, 709.31, 671.06 and 25561.01 ng/cm2, respectively. According to the fitting data of the TQRP active components, skin permeation was mainly due to a combination of passive diffusion and drug release after matrix erosion

Effect of ultrafine comminution on transdermal absorption and rheology of Polygonum cuspidatum ointment / 中草药

Objective: To study the effect of ultrafine comminution on transdermal absorption and rheology of P. cuspidatum ointment (PCO). Methods: Common and ultrafine common powder of P. cuspidatum was got by common and ultrafine comminution technology respectively, and then prepared into common and ultrafine PCO. The skin permeation of common and ultrafine PCO was investigated through in vitro excised mice skin using improved Franz diffusion cell, with polydatin, resveratrol, and emodind as the indexes to compare the effect on the cumulative permeation amount and permeation rate of ointments. Then the effect on the rheology of ointments with apparent viscosity and yield stress as the indexes was compared. Results: The d0.9 of common and ultrafine powder of P. cuspidatum were (210.011 ± 3.468) and (63.496 ± 2.570) μm; And the spans were (5.412 ± 0.055) and (2.913 ± 0.117), respectively. The cumulative permeation amount of polydatin, resveratrol, and emodind of PCO were (2.100 3 ± 0.154 5), (2.114 5 ± 0.341 6), and (6.210 4 ± 0.750 0) μg/cm2, and the permeation rate were (0.175 3 ± 0.022 6), (0.234 0 ± 0.020 2), and (0.337 4 ± 0.051 6) μg/(cm2∙h), respectively. The ultrafine cumulative permeation amounts of polydatin, resveratrol, and emodind of PCO were (14.247 9 ± 4.875 0), (4.399 3 ± 0.628 7), and (6.768 6 ± 0.728 6) μg/cm2, which were 6.8, 2.1, and 1.1 times compared to common PCO; The permeation rates were (0.815 9 ± 0.277 1), (0.313 2 ± 0.043 0), and (0.393 7 ± 0.042 6) μg/(cm2∙h), which were 4.7, 1.3, and 1.2 times compared to common PCO respectively. The cumulative permeation amounts and permeation rates of ultrafine PCO were 6.8, 2.1, 1.1 and 4.7, 1.3, 1.2 times compared to common PCO. The apparent viscosity and yield stress of common and ultrafine PCO were 34.940, 8.865 Pa∙s and 41.211, 7.381 Pa. Conclusion: Compared with common PCO, the transdermal permeability and fineness of ultrafine PCO were improved, and the apparent viscosity and yield stress decreased, which facilitates of spreadability.

Enhancement of transdermal absorption of puerarin by microneedle-assisted microemulsion / 中草药

Objective: To enhance the percutaneous absorption of puerarin, a water insoluble drug, using microneedle-assisted microemulsion. Methods: With puerarin microemulsion as control, in vivo and in vitro experiments were conducted to evaluate permeation amount of puerarin, which was increased by 12.4 times using microneedle-assisted microemulsion. In rat skin microdialysis experiments in vivo, the peak concentration (Cmax) of puerarin in reception medium was (713.51 ± 72.23) ng/mL for microneedle-assisted microemulsion group and (108.56 ± 5.72) ng/mL for microemulsion group; The areas under concentration-time curves (AUCs) of puerarin were (5 021.45 ± 547.09) ng∙h/L for microneedle-assisted microemulsion group and (622.36 ± 41.21) ng∙h/L for microemulsion group, respectively. Compared with microemulsion, the Cmax and AUC of puerarin in rat skin microdialysis experiments in vivo were increased by 5.57 times and 7.07 times, respectively, when microneedle-assisted microemulsion was used. In pharmacokinetic experiments in rats, the Cmax and AUC of puerarin in rat plasma were (234.35 ± 25.02) ng/mL and (3 047.13 ± 486.51) ng∙h/L for the microneedle-assisted microemulsion group. The puerarin concentration in rat plasma for the microemulsion group were lower than the limit of detection. Conclusion: The transdermal absorption of puerarin could be enhanced obviously using microneedle-assisted microemulsion. By conducting this research, a preliminary foundation is laid for the development of novel delivery systems for puerarin.

Equilibrium solubilities, oil-water partition coefficients and in vitro skin permeation features of two constituents in total alkaloids from Strychni Semen / 中成药

AIM To investigate the equilibrium solubilities,oil-water partition coefficients and in vitro skin permeation features of brucine and strychnine in total alkaloids from Strychni Semen.METHODS Saturated dissolution method was applied to determining the equilibrium solubilities of two constituents in ethanol (10％,20％,30％,60％,90％,anhydrous ethanol),trichloromethane,n-octanol and surfactants (0.5％ tween,0.5％ sodium deoxycholate,0.5％ oleic acid).Shake-flask method was adopted in detecting their oil-water partition coefficients in PBS (pH 2.5,4.0,5.0,5.8,6.8,7.0,7.4,9.0).Modified Franz diffusion cell method was used for evaluating their in vitro skin permeation features in PBS,20％ ethanol and anhydrous ethanol.RESULTS Both brucine and strychnine showed the highest equilibrium solubilities in trichloromethane and the lowest equilibrium solubilities in surfactants.The equilibrium solubility of strychnine was higher than that of brucine in ethanol (＞ 20％) or PBS (pH ＜ 8.0),which reached the highest in 60％ ethanol and pH 2.5 PBS,respectively.The similar oil-water partition coefficients of two constituents,proportional to pH value,reached the highest at pH9.0.And they exhibited the highest accumulated transdermal absorptivities in anhydrous ethanol and pH 9.0 PBS,respectively.CONCLUSION Solvent type has obvious effects on the equilibrium solubilities,oil-water partition coefficients and in vitro skin permeation features of both brucine and strychnine.This study can provide a reference for the bioavailability improvement of transdermal drug delivery and development of related preparations.

Equilibrium solubilities, oil-water partition coefficients and in vitro skin permeation features of two constituents in total alkaloids from Strychni Semen / 中成药

AIM To investigate the equilibrium solubilities,oil-water partition coefficients and in vitro skin permeation features of brucine and strychnine in total alkaloids from Strychni Semen.METHODS Saturated dissolution method was applied to determining the equilibrium solubilities of two constituents in ethanol (10％,20％,30％,60％,90％,anhydrous ethanol),trichloromethane,n-octanol and surfactants (0.5％ tween,0.5％ sodium deoxycholate,0.5％ oleic acid).Shake-flask method was adopted in detecting their oil-water partition coefficients in PBS (pH 2.5,4.0,5.0,5.8,6.8,7.0,7.4,9.0).Modified Franz diffusion cell method was used for evaluating their in vitro skin permeation features in PBS,20％ ethanol and anhydrous ethanol.RESULTS Both brucine and strychnine showed the highest equilibrium solubilities in trichloromethane and the lowest equilibrium solubilities in surfactants.The equilibrium solubility of strychnine was higher than that of brucine in ethanol (＞ 20％) or PBS (pH ＜ 8.0),which reached the highest in 60％ ethanol and pH 2.5 PBS,respectively.The similar oil-water partition coefficients of two constituents,proportional to pH value,reached the highest at pH9.0.And they exhibited the highest accumulated transdermal absorptivities in anhydrous ethanol and pH 9.0 PBS,respectively.CONCLUSION Solvent type has obvious effects on the equilibrium solubilities,oil-water partition coefficients and in vitro skin permeation features of both brucine and strychnine.This study can provide a reference for the bioavailability improvement of transdermal drug delivery and development of related preparations.

Effect of Enhancers on in vitro and in vivo Skin Permeation and Deposition of S-Methyl-(L)-Methionine

S-methyl-(L)-methionine (SMM), also known as vitamin U, is commercially available as skin care cosmetic products for its wound healing and photoprotective effects. However, the low skin permeation expected of SMM due to its hydrophilic nature with a log P value of −3.3, has not been thoroughly addressed. The purpose of this study thus was to evaluate the effect of skin permeation enhancers on the skin permeation/deposition of SMM. Among the enhancers tested for the in vitro skin permeation and deposition of SMM, oleic acid showed the most significant enhancing effect. Moreover, the combination of oleic acid and ethanol further enhanced in vitro permeation and deposition of SMM through hairless mouse skin. Furthermore, the combination of oleic acid and ethanol significantly increased the in vivo deposition of SMM in the epidermis/dermis for 12 hr, which was high enough to exert a therapeutic effect. Therefore, based on the in vitro and in vivo studies, the combination of oleic acid and ethanol was shown to be effective in improving the topical skin delivery of SMM, which may be applied in the cosmetic production process for SMM.

Influence of monoolein on progesterone transdermal delivery

abstract This work aimed to investigate in vitro the influence of monoolein (MO) on progesterone (PG) transdermal delivery and skin retention. Information about the role of MO as an absorption enhancer for lipophilic molecules can help on innovative product development capable of delivering the hormone through the skin in a consistent manner, improving transdermal therapy of hormonal replacement. MO was dispersed in propylene glycol under heat at concentrations of 0% (control), 5% w/w, 10% w/w and 20% w/w. Then, 0.6% of PG (w/w) was added to each formulation. Permeation profile of the hormone was determined in vitro for 48 h using porcine skin in Franz diffusion cells. PG permeation doubled when 5% (w/w) of MO was present in formulation in comparison to both the control and higher MO concentrations (10% and 20% w/w). An equal trend was observed for PG retention in stratum corneum (SC) and reminiscent skin (E+D). PG release rates from the MO formulations, investigated using cellulose membranes, revealed that concentrations of MO higher than 5% (w/w) hindered PG release, which indeed negatively reflected on the hormone permeation through the skin. In conclusion, this work demonstrated the feasibility of MO addition (at 5% w/w) in formulations as a simple method to increase transdermal PG delivery for therapies of hormonal replacement. In contrast, higher MO concentrations (from 10% to 20% w/w) can control active release, and this approach could be extrapolated to other lipophilic, low-molecular-weight molecules.

resumo Este trabalho teve como objetivo investigar in vitro a influência de monooleína (MO) na permeação transdérmica de progesterona (PG), bem como sobre a retenção cutânea desse hormônio a fim de (i) liberar de maneira mais consistente hormônio através da pele para melhorar a terapia transdérmica de reposição hormonal e (ii) trazer mais informações sobre o papel da MO como promotor da absorção cutânea de moléculas lipofílicas, tema ainda pouco explorado na literatura. MO foi dispersa em propilenoglicol, a concentrações de 0% (controle), 5%, 10% e 20% (p/p). Adicionou-se, em seguida, 0,6% (p/p) de PG a cada uma das formulações. O perfil de permeação do hormônio foi então determinado in vitro durante 48 h, utilizando pele de porco em células de difusão do tipo Franz. MO a 5% (p/p) foi capaz de duplicar a permeação de PG em comparação ao controle e às concentrações mais elevadas de MO, assim como a retenção de PG no estrato córneo (SC) e epiderme e derme remanescentes (E+D). A velocidade de liberação de PG a partir das formulações foi investigada usando membranas de celulose e este estudo revelou que concentrações de MO superiores a 5% (p/p) impediram a liberacão de PG, o que de fato refletiu de forma negativa na permeação cutânea do hormônio. Concluindo, este trabalho demonstrou a viabilidade da adição de MO a uma formulação como um método simples para aumentar a permeação transdérmica de PG para uso em terapias de reposição hormonal. Por outro lado, altas concentrações de MO (de 10% a 20% p/p) controlam a liberação de PG e este efeito pode ser extrapolado para outras moléculas lipofílicas de baixa massa molecular.

Formulation and characterization of Liquid Crystalline Hydrogel of Agomelatin: In vitro and Ex vivo evaluation.

Objective: The aim of this investigation was the development and characterization of Agomelatin-loaded liquid crystalline (AM-LC) nanoparticles for improved topical application. Methods: AM-LC was formulated with the glyceryl monooleate (GMO) and poloxamer 407 as structure forming agent (lipid) and surfactant respectively, by using emulsification of GMO and poloxamer in water using a hydrotrope (Cubosomes) formation method. The obtained dispersion was characterized for particle size, PDI, zeta potential, entrapment efficiency, surface morphology, in vitro studies. Further, conversion optimised formulation in to cubic gel by incorporating 0.5% w/w of carbopol 934P. The prepared gel was characterized by rheological measurements, surface pH and ex vivo permeation studies through the rat skin. Results: The average particle size of formulations was ranging from 187.6±3.97nm to 225.8±7.54nm and ZP from -14.5±4.65 to -23.5±3.86mV. In vitro drug release from cubosomes exhibited sustained release profile and the optimized formulation (F2) showed cumulative drug release of 83.96±2.43% during 24h. Transmission electron microscopic photographs confirmed that the formed liquid crystalline nanoparticles were cubic in shape. Results suggested that cubic gel exhibited a retarded release rate (53.5 ± 3.21%) than the control gel (95.33 ± 2.28%) containing 0.1% drug solution. Conclusion: The obtained results indicated that cubic gel would be a promising carrier for topical delivery of agomelatin into and across the skin.

Nectandra falcifolia: potential phytopharmaceutical for skin damage protection designed by statistical approach and characterized by photoacoustic spectroscopy

AbstractPhytopharmaceutical products are being used in the treatment and prevention of health problems. Nowadays, the development and evaluation of novel pharmaceutical products is expensive and time consuming. A statistical approach is a good tool for optimal development processes. Nectandra falcifolia (Nees) J.A. Castigl. ex Mart. Crov. & Piccinini, Lauraceae, a Brazilian species, is reported as anti-inflammatory, anti-leishmanial and anti-microbial. However, there is little known about its chemical composition. For other species of Nectandra genus, the presence of antioxidant compounds is reported. In order to optimize the process of obtaining extract with high antioxidant activity, different extraction conditions were tested following a statistical approach. Two sequential experimental designs were used – first, a factorial 23 design, followed by central composite 22. The extracts manufactured by these experimental statistical matrixes had their antioxidant activity and phenolic contents quantified and the response surface plots were fitted in quadratic models and they predicted the best extraction condition for the best antioxidant activity. This standardized extract and its antioxidant activity were better evaluated by two complementary tests (ABTS and Burst respiratory). A topical formulation containing 1% (w/w) of standardized extract was prepared and used for an in vivo skin permeation study using a two-dose application. The photoacoustic spectroscopy was used to analyze the samples from the permeation study and the composition profile of standardized extract. In rat skin samples, the data demonstrated that for the higher dose of topical formulation (5 g/cm2), the standardized extract could cross skin and be seen in epidermis and dermis. This was not the case for the lower dose (2 g/cm2) which was only present in the epidermis. This information suggests that this novel standardized extract of N. falcifoliacould be explored for skin damage prevention or treatment for diseases developed by oxidative damage.

Permeación en piel humana de una nanoemulsión de ftalocianina de aluminio clorada para la optimización de tratamientos tópicos de leishmaniasis cutánea / Human Skin Permeation of a Chloroaluminum Phthalocyanine Nanoemulsion for Optimization of Topical Cutaneous Leishmaniasis Formulations / Permeação em pele humana de uma nanoemulsão de ftalocianina de alumínio clorada para a otimização de tratamentos tópicos de leishmaniose cutânea

Introducción: Las nanoemulsiones son excelentes sistemas de transporte y entrega de fármacos. La ftalocianina de aluminio clorada (PcAlCl) en terapia fotodinámica constituye una alternativa de tratamiento en leishmaniasis cutánea. Objetivo: Determinar la difusión y retención en piel humana de la PcAlCl contenida en una nanoemulsión (nano-PcAlCl) para su optimización en formulaciones tópicas. Materiales y métodos: Se prepararon y caracterizaron fisico-químicamente dos formulaciones (nano-PcAlCl y solución-PcAlCl) y sus vehículos sin-PcAlCl. La permeación se determinó en ensayos en celdas de difusión de Franz y la retención por el método de la cinta adhesiva. La concentración de PcAlCl fue determinada fluorométricamente (nM/cm2). Biopsias de piel fueron analizadas histotécnicamente. Resultados: El tamaño promedio, el potencial Z y el índice de polidispersión de la nano-PcAlCl en agua fue de 132,9 nm, -19,23 y 0,14 y diluida en PBS fue 125,33 nm, -13,69 y 0,139. Las concentraciones de PcAlCl se mantuvieron estables. La PcAlCl no atravesó la piel y fue retenida en sus capas, en estrato córneo y epidermis+dermis con valores de 44,17 nM y 8,48 nM postratamiento con nano-PcAlCl, y 96,90 nM y 9,80 nM postratamiento con solución-PcAlCl. Esta última promovió mayor retención en estrato córneo y ambas formulaciones promovieron similar retención en epidermis+dermis. Se observó desprendimiento del estrato córneo y fragmentación del colágeno. Conclusión: La PcAlCl no atravesó la piel, se retuvo en estrato córneo y epidermis+dermis. Se sugiere realizar ensayos de permeación utilizando piel humana desprovista de estrato córneo y ensayos de distribución en animales con leishmaniasis cutánea.

Introduction: The nanoemulsions constitute excellent drug delivery systems for carrying and delivering active drugs. Chloroaluminum phthalocyanine (ClAlPc) in photodynamic therapy constitutes an interesting alternative in cutaneous leishmaniasis treatment. Objective: To determine the diffusion and retention of ClAlPc contained in a nanoemulsion (nano-ClAlPc) in human skin membranes for optimization of topical formulations. Materials and methods: Two formulations (ClAlPc-nano- and ClAlPc-solution) and vehicles without ClAlPc were prepared and physicochemical characterized. The permeation was tested in Franz-diffusion cells and the retention by the tape stripping method. ClAlPc concentration was determined fluorometrically (nM/cm2). Skin biopsies were analyzed by histologic technics. Results: The ClAlPc-nano average size, zeta potential and polydispersity index diluted in water was 132.9 nm, -19.23 and 0.14 and diluted in phosphate-buffer-saline was 25.33 nm, -13.69 and 0.139. ClAlPc maintains its stability in each formulation. ClAlPc was unable to pass completely through the skin; it was retained in the different skin layers. A ClAlPc retention in stratum corneum and epidermis+dermis was observed with values of 44.17 nM and 8.48 nM after ClAlPc-nano treatment and 96.90 nM and 9.80 nM after ClAlPc-solution treatment. The ClAlPc-solution promoted greater retention in stratum corneum and both formulations showed similar ClAlPc-retention in epidermis+dermis. Histological changes as stratum corneum detachment and collagen-fragmentation were observed. Conclusion: ClAlPc was not able to cross completely the skin, it was retained in stratum corneum and epidermis+dermis Human permeation test using skin membranes without stratum corneum, and distribution assays in cutaneous leishmaniasis-infected animals, are suggested.

Introdução: as nanoemulsões são excelentes sistemas de transporte e entrega de fármacos. A ftalocianina de alumínio clorada (PcAlCl) em terapia fotodinâmica constitui uma alternativa de tratamento em leishmaniose cutânea. Objetivo: determinar a difusão e retenção em pele humana da PcAlCl contida em uma nanoemulsão (nano-PcAlCl) para sua otimização em formulações tópicas. Materiais e métodos: se prepararam e caracterizaram fisico-quimicamente duas formulações (nano-PcAlCl e solução-PcAlCl) e seus veículos sem-PcAlCl. A permeação determinou-se em ensaios em celas de difusão de Franz e a retenção pelo método da fita adesiva. A concentração de PcAlCl foi determinada fluorometricamente (nM/cm²). Biopsias de pele foram analisadas histotecnicamente. Resultados: o tamanho médio, o potencial Z e o índice de polidispersão da nano-PcAlCl em água foi de 132,9 nm, -19,23 e 0,14 e diluída em PBS foi 125,33 nm, -13,69 e 0,139. As concentrações de PcAlCl mantiveram-se estáveis. A PcAlCl não atravessou a pele, foi retido em suas capas. A PcAlCl foi retida em estrato córneo e epiderme+derme com valores de 44,17 nM e 8,48 nM pós-tratamento com nano-PcAlCl e 96,90 nM e 9,80 nM pós-tratamento com solução-PcAlCl. A solução-PcAlCl promoveu maior retenção em estrato córneo e ambas as formulações promoveram similar retenção em epiderme+derme. Observou-se desprendimento do estrato córneo e fragmentação do colágeno. Conclusão: a PcAlCl não atravessou a pele; reteve-se em estrato córneo e epiderme+derme. Sugere-se realizar ensaios de permeação utilizando pele humana desprovida de estrato córneo e ensaios de distribuição em animais com leishmaniose cutânea.

Permeación en piel y biodistribución de una nanoemulsión de ftalocianina de aluminio clorada (PcAlCl) aplicada tópicamente en ratas Wistar / Skin permeation and biodistribution of chloroaluminum phthalocyanine (ClAlPc) nanoemulsion applied topically in Wistar rats

Una formulación tópica en leishmaniasis cutánea debe garantizar la permeación y acumulación del compuesto en la dermis, sitio donde se encuentran los macrófagos infectados con Leishmania. Se determinó la difusión y retención de PcAlCl contenida en una nanoemulsión (nano-PcAlCl) y en solución-PcAlCl y su distribución en ratas Wistar, con piel sana o lesionada quirúrgicamente. La nano-PcAlCl se preparó por el método de emulsificación espontánea y la solución-PcAlCl en mezcla DMSO: Tween 80: agua tipoI; la estabilidad se determinó espectrofotométricamente. La difusión se determinó utilizando celdas de Franz y la retención en el estrato córneo (EC) y la epidermis-dermis (E+D) por "tape stripping". Las formulaciones mantuvieron las características espectroscópicas del compuesto. La PcAlCl no difundió al medio receptor. Después de 12 y 24 horas la retención del compuesto en EC con nano-PcAlCl fue 99,73 y 79,40nM y con solución-PcAlCl 66,73 y 57,01nM; en E+D la retención con nano-PcAlCl fue 40,94 y 62,49nM y con solución-PcAlCl 81,92 y 50,28nM. En EC la nano-PcAlCl registró mayor retención y en E+D la solución-PcAlCl, registró mayor retención a las 12 horas y la nano-PcAlCl a las 24 horas. Se observó desprendimiento y disminución en las capas del epitelio. El tratamiento con nano-PcAlCl retuvo el compuesto en EC y E+D de los animales con valores de 6,43nM y 33,18nM con piel sana y 0,99nM y 17,08 con piel lesionada; valores menores de 1,92nM fueron detectados sólo en pulmón. El tratamiento con solución-PcAlCl retuvo el compuesto en EC y E+D de los animales con valores de 31,86 y 202,40nM con piel sana y 5,93 y 63,83nM con piel lesionada; se encontraron valores de 2,36nM y 20,33nM en los pulmones y valores entre 1,58 y 5,80nM en otros órganos. La piel lesionada presentó regeneración del epitelio, desprendimiento de queratina, infiltrado celular y neovascularización. La PcAlCl retenida en EC y E+D indicó la eficacia de las formulaciones para penetrar el EC y retener el compuesto en las capas viables de la piel. El tratamiento con nano-PcAlCl permeó el EC, se retuvo en E+D y no presentó distribución hacia órganos.

A successful formulation contained aluminum phthalocyanine chloride (ClAlPc) able for cutaneous leishmaniasis (CL) ensures the skin permeation and retention of the compound in dermis, a place where macrophages infected with Leishmania are located. The aim of this study was to determine the ClAlPcex vivo permeation and retention in Wistar rat skin and its distribution in animals with healthy skin and surgically damaged skin. Two formulations were prepared: nanoemulsion (ClAlPc-nano) and solution (ClAlPc-solution). The diffusion was determined using Franz diffusion cells with Wistar rat skin as membrane after 12 and 24 hours of testing. Retention in stratum corneum (SC) and epidermis plus dermis (E+D) was determined by the tape stripping method and organic solvent extraction. The distribution was performed after the topical application of formulations analyzing the CLAlPc concentration in the skin layers and organs by fluorometry. The results were expressed as nM/mg of tissue of ClAlPc. Simultaneously, skin biopsies were taken in order to determine their histological characteristics. ClAlPc formulations were effective in maintaining compound solubility and spectroscopic characteristics. ClAlPc was unable to pass completely through the skin; its skin retention was related with the used formulation, time of assays and type of skin layer. After 12 and 24 hours, the SC retention induced by ClAlPc-nano treatment was 99.73 and 79.40nM and by ClAlPc-solution was 66.73 and 57.01nM. In E+D the retention induced by ClAlPc-nano was 40.94 and 62.49nM and by ClAlPc-solution was 81.92 and 50.28nM. In SC, ClAlPc-nano showed greater retention after 12 and 24 hours, while in E+D, ClAlPc-solution was greater retained at 12 hours and ClAlPc-nano at 24 hours. After the permeation assays, detachment and reduction in epithelial layers were observed in skin membranes. In Wistar rats, ClAlPc-nano placed on healthy skin retained the compound in E+D and SC with values of 33.18nM and 6.43nM and placed on damaged skin retained in E+D in SC with values of 17.08nM and 0.99nM respectively; no organs distribution occur, except in lung where values of 0.82nM in animals with healthy skin and 1.92nM in animals with damaged skin were observed. ClAlPc-solution induced retention of 31.86 in SC and 202,40nM in E+D placed on healthy skin and 5.93 in SC and 63.83nM E+D placed on damaged skin; concentrations in lung with values of 2,36nM after application in animals with healthy skin and 20,33nM in animals with damaged skin were observed. In addition, ClAlPc-solution promoted, after application on damaged skin, distribution of ClAlPc to other organs with values between 1.58 and 5.80nM. In animals without skin injury, normal histologic skin anatomy were observed after treatment. In contrast, epithelial regeneration, detachment of keratin, loss of cellular differentiation, cellular infiltration and neovascularization were observed in animals with skin injury. The efficacy of the formulation to penetrate the SC and be retained in the viable skin layers was demonstrated. The in vivo ClAlPc-biodistribution was related on its concentration and skin state. A nanoemulsion contained ClAlPc, represents a good system of drug delivery because induce both the SC penetration and E+D retention, without systemic organ distribution even when presented tissue repair and regeneration. A ClAlPc-nano prepared in this work constitutes a good formulation for the topical application of ClAlPc in LC treatment.

In vitro evaluation of transdermal nicotine delivery systems commercially available in Brazil

The aim of this study was to develop and validate a method for evaluating the release and skin permeation from transdermal nicotine patches using the vertical diffusion cell (VDC). The VDC is an experimental apparatus employed in research, development, and the pharmaceutical field because it can simulate conditions closest to those established in clinical trials. Two transdermal nicotine delivery systems marketed in Brazil to release 14 mg over 24 hours were evaluated. Release studies were carried out using a regenerated cellulose dialysis membrane and permeation studies were carried out using excised porcine ear skin. The results indicated that nicotine release from both evaluated patches follows Higuchi's release kinetics, while skin permeation studies indicated zero-order release kinetics. Nicotine release rates were different between both evaluated patches, but drug permeation rates were not significantly different. According to validation studies, the method was appropriate for evaluating in vitro performance of nicotine patches. The proposed method can be applied to in vitro comparative studies between different commercial nicotine patches and may be used as an auxiliary tool in the design of new transdermal nicotine delivery systems.

O objetivo deste trabalho foi o desenvolvimento e a validação de metodologia empregando a célula de difusão vertical para avaliação da liberação e permeação cutânea in vitro de nicotina a partir de adesivos transdérmicos. A célula de difusão vertical é considerada um aparato experimental importante em pesquisa e desenvolvimento e pode simular condições in vitro próximas aquelas observadas em ensaios clínicos. Neste trabalho foram avaliados dois dispositivos transdérmicos comercializados no Brasil para liberação controlada de 14 mg de nicotina em um período de 24 horas. Realizaram-se ensaios de liberação, usando membranas de diálise de celulose regenerada, e estudos de permeação cutânea, usando pele de orelha de porcos. Os resultados indicaram que a liberação da nicotina em ambos os dispositivos transdérmicos avaliados seguiu a cinética de Higuchi, enquanto que a permeação cutânea seguiu cinética de ordem zero. As velocidades de liberação foram diferentes para os dispositivos comerciais avaliados, entretanto não foram encontradas diferenças significativas para as velocidades de permeação cutânea. Conforme os estudos de validação, a metodologia mostrou-se apropriada para a avaliação in vitro da liberação e permeação cutânea a partir de adesivos transdérmicos de nicotina. O método proposto foi aplicado em estudos comparativos in vitro entre adesivos transdérmicos comerciais contendo nicotina. Deste modo, o método também pôde ser considerado como ferramenta útil que poderia ser aplicada durante o desenvolvimento de novas formulações transdérmicas para liberação de nicotina.

Preventive Effects of Multi-Lamellar Emulsion on Low Potency Topical Steroid Induced Local Adverse Effect

BACKGROUND: Topical steroid treatment induces diverse local Wand systemic adverse effects. Several approaches have been tried to reduce the steroid-induced adverse effects. Simultaneous application of physiological lipid mixture is also suggested. OBJECTIVE: Novel vehicles for topical glucocorticoids formulation were evaluated for the efficacy of reducing side-effects and the drug delivery properties of desonide, a low potency topical steroid. METHODS: Transcutaneous permeation and skin residual amount of desonide were measured using Franz diffusion cells. The in vivo anti-inflammatory activity was evaluated using murine model. RESULTS: Topical steroids formulation containing desonide, in either cream or lotion form, were prepared using multi-lamellar emulsion (MLE), and conventional desonide formulations were employed for comparison. MLE formulations did not affect the anti-inflammatory activity of the desonide in phobol ester-induced skin inflammation model, compared with conventional formulations. While the penetrated amounts of desonide were similar for all the tested formulations at 24 hours after application, the increased lag time was observed for the MLE formulations. Interestingly, residual amount of desonide in epidermis was significantly higher in lotion type MLE formulation. Steroid-induced adverse effects, including permeability barrier function impairment, were partially prevented by MLE formulation. CONCLUSION: Topical desonide formulation using MLE as a vehicle showed a better drug delivery with increased epidermal retention. MLE also partially prevented the steroid-induced side effects, such as skin barrier impairment.

Evaluation of Caffeine Gels on Physicochemical Characteristics and In Vivo Efficacy in Reducing Puffy Eyes.

The eyelids are the thinnest skin in the body, leading to be easy for the blood vessels to show through the skin caused a swollen and dark appearance called puffy eyes. Placing refrigerated damp tea bags on the eyelids has been believed for a long time that it can reduce the puffy eyes due to the vasoconstriction of caffeine. This study aimed to characterize physicochemical properties and to determine in vivo efficacy in reducing puffy eyes of the prepared caffeine gels. The formulation composed of 3% caffeine, 2% ethanol, 0.3% Uniphen® P-23, 7.5% propylene glycol, 0.5% Carbopol® Ultrez-21 and water to 100% was selected for eye irritation test and efficacy evaluation since it possessed good characteristics and provided sustained skin permeation. The 34 volunteers (18 women, 16 men) who easily developed puffy eyes after going to bed without sleep and with no irritation to caffeine gel as well as its gel base were treated with the gels in a randomized, double-blind, placebo-controlled trial. The skin permeation profiles showed that all caffeine gels allowed caffeine to permeate through the newborn pig skin. However, the overall efficacy of the selected caffeine gel in reducing puffy eyes was not significantly different from that of its gel base. It could be concluded that the cooling effect of the hydrophilic gels was the main parameter in reduction of eye puffiness rather than the vasoconstriction of caffeine.

Development, stability and in vitro permeation studies of gels containing mometasone furoate for the treatment of dermatitis of the scalp / Estabilidade, desenvolvimento e in vitro estudos de permeação de gel contendo furoato de mometasona para o tratamento da dermatite do couro cabeludo

Dermatological inflammatory diseases such as atopic dermatitis, psoriasis and seborrhoeic dermatitis often affect the scalp and the eyebrows. Although there are many dosage forms available, these are particularly critical anatomic regions for application of topical formulations because of the presence of hair. Lotions are therefore the recommended type of drug delivery system for these areas. The presence of hair may limit the application and thus the acceptability of the formulation and its compliance. Because of its low apparent viscosity, lotion application is unpleasant. Gels, given their consistency and adhesiveness, are a suitable alternative to lotions in this situation. The aim of this study was to formulate a stable gel containing mometasone furoate, which is an anti-inflammatory and anti-pruritic corticosteroid, in order to improve topical treatment of scalp dermatitis. In this study, pharmaceutical development, physical-chemical characterization, stability and in vitro permeation studies were performed. In terms of the pH, viscosity, assay and macroscopic and microbiological properties, the gel was stable over the period of study. The in vitro permeation studies allowed the characterization of the mometasone furoate permeation profile for the gel through different membranes. Mometasone furoate presented a slow permeation through the skin. This gel appears safe for topical application.

Afecções dermatológicas do tipo inflamatório como a dermatite atópica, psoríase e dermatite seborreica, afetam freqüentemente o couro cabeludo e sobrancelhas. Apesar de existirem várias formas farmacêuticas para o seu tratamento, apenas as loções são indicadas para estas zonas, mas devido à baixa viscosidade, a aplicação de loções torna-se desagradável. Os geles, pela maior consistência e capacidade de adesão, apresentam-se como alternativa nesta situação. Neste trabalho procedeu-se ao desenvolvimento galênico de um gel com furoato de mometasona, que é um potente corticóide de última geração, com um rácio melhorado de risco/benefício. Foram avaliadas as características físico-químicas, a estabilidade e foram realizados ensaios de permeação in vitro. O gel obtido apresenta características organolépticas e reológicas adequadas ao fim a que se destina tendo-se apresentado estável química, física e microbiologicamente durante o tempo do ensaio. Os estudos de permeação in vitro permitiram caracterizar a formulação através de diferentes membranas. A membrana biológica (pele) não permite uma grande permeação do fármaco o que poderá sugerir que esta formulação é segura para aplicação tópica.