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Carotenoids and coenzyme Q10 are naturally occurring antioxidant compounds that are also found in human skin. These bioactive compounds have been the focus of considerable research due to their antioxidant, anti-inflammatory, and photoprotective properties. In this review, the current state of the art in the encapsulation of carotenoids and coenzyme Q10 in lipid nanoparticles to improve their bioavailability, chemical stability, and skin absorption is discussed. Additionally, the main findings are highlighted on the cytotoxic and photoprotective effects of these systems in the skin.

Imiquimod (IMQ), an immune response modifier, is used for topical treatment of basal cell carcinoma and actinic keratosis. The very poor aqueous solubility of imiquimod gives rise to difficulties in designing aqueous formulations with this drug. One approach that is widely used to enhance drug solubility is complexation with cyclodextrins. The formation of the inclusion complex between IMQ and β-cyclodextrin was investigated in solution and in solid state. IMQ aqueous solubility was improved in the presence of citric acid. The experimental results and molecular modeling indicated the formation of the inclusion complex in aqueous solution of citric acid pH 3.0; however, the low apparent stability constant suggested weak interaction between β-cyclodextrin and IMQ which hampered the use of this approach to improve imiquimod aqueous solubility and the development of an aqueous formulation containing IMQ in the same concentration as in the commercial product.

International audience; Lycopene, beta-carotene, coenzyme Q10, and lutein are minor constituents of palm oil that are removed during biodiesel production to produce light-colored oils. With the aim to investigate the recovery of these valuable compounds, a separation method was developed to quantify carotenoids and coenzyme Q10 in palm oil by ultra-highperformance supercritical fluid chromatography. Due to the presence of interferents

In this study, an analytical method based on Design of Experiments and response surface methodology for the separation of lycopene, beta-carotene, coenzyme Q10, and lutein was developed by ultra-high performance supercritical fluid chromatography technique. A Central Composite Design was used to evaluate the influence of temperature, pressure, and ethanol percentage on the retention and separation factors of these compounds. In the designed experiments, the temperature was varied between 25 and 50 °C (298 and 323 K), the pressure within the interval of 1500 and 2200 psi (10 and 15 MPa), and the ethanol percentage between 15 and 24 (v/v) %. Each variable was tested at 3 levels and 5 replicated central points were added. It was found for the studied system that the ethanol percentage and pressure were the parameters that most influenced the retention factors whereas the ethanol percentage, pressure, and temperature affected the separation factors. Quadratic models were necessary to describe the retention and separation of these compounds. Furthermore, interactions among the factors were observed, justifying the DOE approach used in this work. Considering the retention and separation factors, the selected operating conditions for further experiments were: 15.5 % of ethanol at 40 °C (313 K) and 1500 psi (10 MPa).

Orientadores: Cesar Costapinto Santana, Marisa Masumi Beppu, Márcia Cristina Breitkreitz Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Engenharia Química Resumo: Neste estudo, método para separação e quantificação do licopeno, betacaroteno, coenzima Q10 e luteína no óleo de palma foi desenvolvido por cromatografia com fluido supercrítico de ultra alta eficiência (UHPSFC). Primeiramente, as condições de operação foram otimizadas com a mistura padrão. Os analitos foram separados em menos de 7 minutos nas condições de pressão de 1500 psi, temperatura 40 °C e porcentagem de etanol 15,5%. No entanto, essas condições de operação não se mostraram adequadas para a separação dos compostos bioativos no óleo de palma devido à co-eluição dos mesmos com componentes da matriz. Novas condições experimentais foram avaliadas e as condições de pressão de 1600 psi, temperatura 40 °C e porcentagem de etanol 18% foram selecionadas. O método quimiométrico Análise Multivariada de Curvas com Mínimos Quadrados Alternantes (MCR-ALS) foi empregado na análise dos dados cromatográficos para identificar e quantificar os compostos investigados. A concentração determinada para o betacaroteno, coenzima Q10 e luteína foi 176, 8,29 e 2,90 ug/mL, respectivamente. O licopeno não foi quantificado devido à baixa pureza do padrão secundário. A concentração desses compostos foi determinada também por espectroscopia no infravermelho com transformada de Fourier (FTIR). Os resultados apresentaram concordância com os resultados obtidos por UHPSFC usado como referência. A concentração determinada para o betacaroteno, coenzima Q10 e luteína foi 178, 12,8 e 2,90 ug/mL, respectivamente. O estudo mostrou que as técnicas UHPSFC e FTIR podem ser empregadas para quantificação de constituintes minoritários do óleo de palma como os carotenoides e a coenzima Q10 Abstract: In this study, a method for separation and quantification of lycopene, beta-carotene, coenzyme Q10 and lutein in palm oil was developed by ultra-high performance supercritical fluid chromatography (UHPSFC). First, the operating conditions were optimized with a standard mixture. Analytes were separated in less than 7 minutes under conditions of pressure 1500 psi, temperature 40 °C and 15.5% of ethanol. However, these operating conditions were not adequate for separation of the bioactive compounds in palm oil due to co-elution of the target compounds with matrix constituents. New experimental conditions were evaluated and the conditions of pressure 1600 psi, temperature 40 °C and 18% of ethanol were selected. The chemometric method Multivariate Curve Resolution with Alternating Least Squares (MCR-ALS) was applied on the chromatographic data to properly identify and quantify the target compounds. Concentration of beta-carotene, coenzyme Q10 and lutein was determined as 176, 8.29 and 2.90 ug/mL, respectively. Lycopene was not quantified because of the low purity of its secondary standard. Concentration of the bioactive compounds were also determined by Fourier transform infrared spectroscopy (FTIR). The results showed good agreement with results obtained by UHPSFC used as reference method. Concentration of beta-carotene, coenzyme Q10 and lutein was determined as 178, 12.8 and 2.90 ug/mL, respectively. The study showed that UHPSFC and FTIR techniques may be employed for quantification of palm oil minor constituents as carotenoids and coenzyme Q10 Doutorado Engenharia Química Doutora em Engenharia Química CNPQ 140467/2015-7

Orientador: Francisco Benedito Teixeira Pessine Dissertação (mestrado) - Universidade Estadual de Campinas, Instituto de Química Resumo: O Imiquimod é um fármaco com propriedades imunomodulatórias, disponível na forma de creme para tratamento tópico de certas patologias da pele como carcinoma basocelular e ceratose actínica. O contato direto do medicamento com a pele pode causar desconforto durante o tratamento. Uma das alternativas para minimizar os efeitos adversos é a utilização de sistemas carreadores que evitam o contato direto do agente com a pele. A ?-ciclodextrina foi empregada como agente carreador neste estudo e o complexo de inclusão obtido foi caracterizado em solução e no estado sólido. As técnicas espectroscópicas de absorção UV/Vis e ressonância magnética nuclear foram utilizadas para caracterizar o complexo de inclusão em solução. Essas técnicas permitiram obter a constante de equilíbrio de associação (Kc), a estequiometria do complexo formado e evidências de sua geometria. A caracterização do complexo no estado sólido foi realizada por calorimetria diferencial de varredura, termogravimetria, difração de raios X e microscopia eletrônica de varredura. Os resultados indicaram a presença de estrutura amorfa que pode ser atribuída a amorfização dos componentes devido à liofilização do complexo e também à formação do complexo de inclusão. A estrutura tridimensional do complexo obtida por modelagem molecular apresentou concordância com os resultados experimentais observados pela técnica de RMN 1H ROESY 1D. Os valores baixos de Kc e da eficiência de complexação indicam fraca interação entre o Imiquimod e a ?-ciclodextrina. Os resultados demonstram que a ?-ciclodextrina não é o sistema carreador mais adequado para aumentar a solubilidade aquosa do Imiquimod Abstract: Imiquimod, an immune response modifier, is used for topical treatment of basal cell carcinoma and actinic keratosis. Local skin reactions can occur in the treatment area. An alternative to minimize adverse events is to use drug delivery systems which avoid drug skin contact. ?-cyclodextrin was used as drug delivery system in this study and the inclusion complex was characterized in solution and in solid state. UV/Vis absorption spectroscopy and nuclear magnetic resonance were employed to study the inclusion complex in solution. Those techniques allowed to obtain the equilibrium constant (Kc), the complex stoichiometry and insight on the geometry. The inclusion complex characterization in solid state was performed by differential scanning calorimetry, thermogravimetry, X-ray diffraction and scanning electron microscopy. The results suggest the presence of amorphous structure which can be attributed not only to components amorphization due to lyophilization but also to complex formation. The complex tridimensional geometry was obtained by molecular modeling and agrees with the experimental results observed by NMR 1H ROESY 1D experiments. The low values of Kc and complex efficiency suggest weak interaction between Imiquimod and ?-cyclodextrin. In addition to those, the results showed that ?-cyclodextrin is not the most suitable drug delivery system to improve Imiquimod aqueous solubility Mestrado Físico-Química Mestra em Química