VALIDATION OF A SIMPLE METHOD FOR SIMULTANEOUS DETERMINATION OF LIPOIC ACID AND RESVERATROL BY HIGH PERFORMANCE LIQUID CHROMATOGRAPHY

A high-performance liquid chromatography-ultraviolet (HPLC-UV) method was developed and validated for simultaneous determination of Resveratrol (RSV) and Lipoic Acid (LA). A C18 column was used with a mobile phase consisting of acetonitrile and 0.01M phosphoric acid (60:40). The detection wavelength was at 235 nm. The method was specific in the presence of pharmaceutical excipients widely used in solid dosage forms or lipid-core nanocapsules. The results demonstrated linearity between 5 and 50 µg/mL for RSV and 30 and 120 µg/mL for LA. The method presented precision and accuracy (RSD <5%). In addition, the developed method was considered robust. Therefore, the developed method can be applied successfully for simultaneous determination of RSV and LA in the proposed conditions, with a potential application to assay both drugs in several dosage forms

Development of a clioquinol nanocarrier as a new, promising option for the treatment of dermatomycosis

Dermatomycosis is a common fungal infection, and its treatment is limited by few antifungal agents. Clioquinol (CQ) is an antiparasitic agent that has been studied for new uses, such as antifungal and antiviral applications. CQ was incorporated into a lipid-based nanocarrier as a new, promising option for dermatomycosis. This study aimed to develop a CQ-loaded lipid-based nanocarrier for cutaneous application and to evaluate its antifungal activity. CQ-loaded nanoformulation (LBN-CQ) was developed using the ultrasonication method, and the particle size, polydispersity index (PDI), pH, zeta potential, and drug content were monitored for 45 days. To evaluate antifungal activity, broth microdilution and a time-kill assay were performed. LBN-CQ presented a particle size of 91 3 nm and PDI of 0.102 0.009. The zeta potential and pH values were 9.7 2.0 mV and 6.0 0.1, respectively. The drug content was 96.4 2.3%, and the encapsulation efficiency was 98.4%. LBN-CQ was able to reduce the minimum inhibitory concentration (MIC) in a 2-fold or 4-fold manner in most of the tested strains. Additionally, LBN-CQ presented stable fungistatic action that was not concentration- or time-dependent. In conclusion, the developed CQ-loaded nanocarrier is a promising treatment for skin fungal infections and a promising candidate for future randomized clinical trials

Lamivudine and zidovudine-loaded nanostructures : green chemistry preparation for pediatric oral administration

Here, we report on the development of lipid-based nanostructures containing zidovudine (1 mg/mL) and lamivudine (0.5 mg/mL) for oral administration in the pediatric population, eliminating the use of organic solvents, which is in accordance with green chemistry principles. The formulations were obtained by ultrasonication using monoolein (MN) or phytantriol (PN), which presented narrow size distributions with similar mean particle sizes (~150 nm) determined by laser diffraction. The zeta potential and the pH values of the formulations were around 4.0 mV and 6.0, respectively. MN presented a slightly higher incorporation rate compared to PN. Nanoemulsions were obtained when using monoolein, while cubosomes were obtained when using phytantriol, as confirmed by Small-Angle X-ray Scattering. The formulations enabled drug release control and protection against acid degradation. The drug incorporation was effective and the analyses using an electronic tongue indicated a difference in palatability between the nanotechnological samples in comparison with the drug solutions. In conclusion, PN was considered to have the strongest potential as a novel oral formulation for pediatric HIV treatment

Desenvolvimento tecnológico de nanoemulsão contendo ácido azelaico e avaliação da inibição da tirosinase, permeação cutânea e perfil sensorial

O ácido azelaico é um fármaco amplamente utilizado como tratamento em diversas doenças de pele, como acne, rosácea e melasma. A utilização de sistemas nanoestruturados para aplicação tópica se mostra interessante visto que o menor tamanho de partícula proporciona uma melhor entrega de fármacos até o seu sítio de ação. É promissor o desenvolvimento de formulações capazes de diminuir os efeitos adversos do ácido azelaico e intensificar sua eficácia no tratamento de desordens pigmentárias da pele, aliado ao desenvolvimento de uma formulação com controle de permeação e perfil sensorial que facilite a adesão ao tratamento. O objetivo do presente trabalho é desenvolver uma nanoemulsão contendo ácido azelaico e realizar ensaios da tirosinase, permeação cutânea e análise sensorial da formulação desenvolvida. A nanoemulsão foi preparada através da técnica de homogeneização a alta velocidade. A caracterização físico-química avaliou os parâmetros de diâmetro médio de partícula e distribuição do tamanho de partícula pela técnica de difração de laser, o potencial zeta foi medido por mobilidade eletroforética, o pH por potenciometria e teor e eficiência de encapsulação por CLAE. A morfologia foi observada por microscopia eletrônica de transmissão. A nanoemulsão foi estável por 30 dias a 30°C/ 65% UR. A formulação apresentou teor de 10 mg/mL, tamanho de partícula de 419 ± 23 nm, distribuição monomodal, eficiência de encapsulação de 84,65%, potencial zeta de -10,9 ± 0,44 mV e pH de 5,01 ± 0,01. Para verificar a eficácia despigmentante da formulação foi realizado o ensaio in vitro de inibição de tirosinase, onde a nanoemulsão se mostrou mais eficaz que o controle com o fármaco na sua forma livre. O ensaio de permeação cutânea in vitro em células de difusão de Franz foi realizado com pele de orelha de porcos durante 24 horas e ele demonstrou que a formulação nanotecnológica conseguiu atingir as camadas mais profundas da pele (epiderme viável e derme), permitindo que o fármaco alcance o seu sítio de ação, facilitando a inibição da síntese de melanina. Foi realizada análise sensorial descritiva, com 16 voluntários demonstrando que a formulação apresentou maior espalhabilidade e menor brilho que um produto já disponível no mercado. Portanto, a nanoemulsão desenvolvida se mostra promissora para utilização no tratamento de melasma, inclusive o dérmico.Azelaic acid is a drug commonly used in the treatment of several skin diseases such as acne, rosacea and melasma. Nanostructured systems for topical application are interesting because its smaller particle size lead to a better drug delivery to its action site. Therefore, it is promising to develop formulations able to lower azelaic acid’s side effects and increase its efficacy as a skin whitening agent as well as control its permeation and shows a sensory profile that helps with patient adherence. The aim of the present work is to develop an azelaic-acid loaded nanoemulsion, evaluating its tyrosinase inhibition, skin permeation and sensory profile. The nanoemulsion was prepared using high shear homogenization. Its characterization was conducted evaluating the average particle diameter through laser diffraction, the zeta potential by eletrophoretic mobility, pH by potentiometry and drug content and encapsulation efficiency by HPLC. The morphology of the nanoemulsion was observed by transmission electron microscopy. The product was stable for 30 days at 30°C/ 65 % RH. The theoretical drug content was 10 mg/mL and the particle size 419 ± 23 nm with a monomodal distribution profile, encapsulation efficiency of 84,65% and the zeta potencial was -10,9 ± 0,44 mV while the pH was 5,01 ± 0,01. To evaluate the formulation’s whitening efficacy, tyrosinase inhibition was calculated and the azelaicacid loaded nanoemulsion was more effective than the control with the drug in its free form. The in vitro permeation study using Franz diffusion cells was conducted for 24 hours, using pig ear skin and showed that the formulation was able to permeate through the skin and reach the deeper layers (viable epidermis and dermis), allowing the drug to reach its action site, improving the melanin synthesis inhibition. To help understand the sensory profile of the nanoemulsion, a descriptive sensory evaluation was conducted with 16 volunteers. The nanoemulsion’s sensory profile showed a better spreadability and lower shine comparing with a product already available in pharmacies. Hence, the azelaic acid-loaded nanoemulsion developed in this word seems to be promising as a treatment for pigmentary skin disorders as dermal melasma

Revista de Microbiologia

Introduction Infections associated with medical devices are often related to colonization by Candida spp. biofilm; in this way, numerous strategies have been developed and studied, mainly in order to prevent this type of fungal growth. Aim Considering the above, the main objective of the present study is to make a rational choice of the best antifungal therapy for the in vitro treatment of the biofilmon venous catheters, proposing an innovative formulation of a film-forming system to coat the surface in order to prevent the formation of biofilms. Methodology Anidulafungin, fluconazole, voriconazole, ketoconazole, amphotericin B, and the association of anidulafungin and amphotericin B were tested against biofilms of C. albicans, C. tropicalis, and C. parapsilosis strains in microtiter plates and in a polyurethane catheter. Besides, anidulafungin, amphotericin B, and the combination of both were incorporated in a filmforming system and were evaluated against biofilm. Results The superior activity of anidulafungin was demonstrated in relation to the other antifungal agents. Although amphotericin B showed good activity, high concentrations were required. The combination showed a synergistic action, in solution and in the formulation, showing excellent results, with activity above 90%. Conclusion Due to the superiority of anidulafungin and the synergistic activity of the combination, these alternatives were the most promising options for use in a formulation proposal as a new strategy to combat the Candida spp. biofilm. These formulations demonstrated high in vitro performance in the prevention of biofilms, indicating that they are candidates with great potential for in vivo tests

Development of a Clioquinol Nanocarrier as a New, Promising Option for the Treatment of Dermatomycosis

Dermatomycosis is a common fungal infection, and its treatment is limited by few antifungal agents. Clioquinol (CQ) is an antiparasitic agent that has been studied for new uses, such as antifungal and antiviral applications. CQ was incorporated into a lipid-based nanocarrier as a new, promising option for dermatomycosis. This study aimed to develop a CQ-loaded lipid-based nanocarrier for cutaneous application and to evaluate its antifungal activity. CQ-loaded nanoformulation (LBN-CQ) was developed using the ultrasonication method, and the particle size, polydispersity index (PDI), pH, zeta potential, and drug content were monitored for 45 days. To evaluate antifungal activity, broth microdilution and a time-kill assay were performed. LBN-CQ presented a particle size of 91 &plusmn; 3 nm and PDI of 0.102 &plusmn; 0.009. The zeta potential and pH values were &minus;9.7 &plusmn; 2.0 mV and 6.0 &plusmn; 0.1, respectively. The drug content was 96.4 &plusmn; 2.3%, and the encapsulation efficiency was 98.4%. LBN-CQ was able to reduce the minimum inhibitory concentration (MIC) in a 2-fold or 4-fold manner in most of the tested strains. Additionally, LBN-CQ presented stable fungistatic action that was not concentration- or time-dependent. In conclusion, the developed CQ-loaded nanocarrier is a promising treatment for skin fungal infections and a promising candidate for future randomized clinical trials

Development of a Clioquinol Nanocarrier as a New, Promising Option for the Treatment of Dermatomycosis

Dermatomycosis is a common fungal infection, and its treatment is limited by few antifungal agents. Clioquinol (CQ) is an antiparasitic agent that has been studied for new uses, such as antifungal and antiviral applications. CQ was incorporated into a lipid-based nanocarrier as a new, promising option for dermatomycosis. This study aimed to develop a CQ-loaded lipid-based nanocarrier for cutaneous application and to evaluate its antifungal activity. CQ-loaded nanoformulation (LBN-CQ) was developed using the ultrasonication method, and the particle size, polydispersity index (PDI), pH, zeta potential, and drug content were monitored for 45 days. To evaluate antifungal activity, broth microdilution and a time-kill assay were performed. LBN-CQ presented a particle size of 91 ± 3 nm and PDI of 0.102 ± 0.009. The zeta potential and pH values were −9.7 ± 2.0 mV and 6.0 ± 0.1, respectively. The drug content was 96.4 ± 2.3%, and the encapsulation efficiency was 98.4%. LBN-CQ was able to reduce the minimum inhibitory concentration (MIC) in a 2-fold or 4-fold manner in most of the tested strains. Additionally, LBN-CQ presented stable fungistatic action that was not concentration- or time-dependent. In conclusion, the developed CQ-loaded nanocarrier is a promising treatment for skin fungal infections and a promising candidate for future randomized clinical trials