Le but général de ce travail correspond à l’amélioration de la biodisponibilité de principes actifs connus pour leur faible biodisponibilité (testostérone) ou pour leur caractère lipidique (acides gras oméga 3). Des systèmes nanoparticulaires à base de lipides et des systèmes nanocristaux ont été développés notamment dans le cas de la testostérone, afin d’obtenir une biodisponibilité supérieure au système oral actuellement commercialisé, Andriol Testocaps®. L’autre partie de ce travail consistait en la conception d’une formule d’acides gras omega -3 dans des nanoparticules lipidiques, susceptibles malgré l’utilisation d’une huile de poisson bon marché comme source d’acides gras omega-3, de n’avoir que peu d’effets sur le goût et l’odorat tout en s’avérant stable. Le développement de systèmes oraux à base de testostérone a été possible autant sur la base de la technologie des nanoparticules lipidiques (Nanostructured Lipid Carriers, NLC), que sur celle des nanocristaux. Dans les deux cas, les systèmes développés ont permis de répondre aux exigences en matière d’incorporation (NLC) et de stabilité (NLC et suspensions Nano). Les NLC ont permis d’incorporer jusqu’à 30% d’undecanoate de testostérone en phase lipidique. La formulation a également été possible avec différents lipides, susceptibles, d’augmenter l’absorption lymphatique et de ce fait également la biodisponibilité de l’hormone. Les nanocristaux ont pu être produits à partir de la testostérone (T) ainsi que d’undecanoate de testostérone (TU), avec des tailles moyennes respectives d’environ 470 nm (TU) et 860 nm (T). Cette taille particulaire doit permettre une absorption lymphatique accrue. Les biodisponibilités des systèmes développés à base de NLC, se sont avérées, chez le rat Wistar, toujours plus élevées que la formulation commerciale, quand ils ont été administrés sans lipides additionnels ce qui permet de supposer, que l’influence simultanée de l’absorption de nourriture sur la biodisponibilité devrait être moins prononcée qu’elle ne l’est pour l’Andriol Testocaps®. En partant de ces résultats, à savoir l’augmentation de la biodisponibilité orale avec les nanoparticules lipidiques, le développement d’un système de nanoparticules avec les acides gras oméga-3 d’huile de poisson bon marché était un pas logique. La biodisponibilité orale des acides gras oméga-3 est largement supérieure à celle du TU (environ 70 %). L’utilisation de la technologie NLC a ainsi permis la réduction de l’odeur et du goût du produit. La formulation avait un pourcentage remarquablement élevé de 70 % en phase lipidique tout en restant pâteuse et redispersible. Ceci permet d’envisager son utilisation dans des boissons et dans la nutrition ce qui facilitera l’assistance des patients (et donc la biodisponibilité) avec les acides gras omega-3 essentiels. / The overall goal of this work consisted in ameliorating the bioavailability of drugs known for their poor hydrosolubility (testosterone) or for their lipidic character (omega-3 fatty acids). This was achieved using lipid nanoparticle systems and nanocrystals In case of testosterone the work consisted of the development of an oral dosage form with superior properties compared to the currently commercially available oral system (Andriol Testocaps®). The other part of this work was the design of a lipid nanoparticle-based omega- 3 fatty acid formulation, which, despite the use of cheap fish oil as source of omega-3 fatty acids, has low smell and taste properties while nevertheless being stable. The development of the oral testosterone drug delivery system was accomplished on the basis of lipid nanoparticles technology and also using drug nanocrystal technology. In both cases, systems could be developed that met the requirements with regards to drug loading (NLC) and stability (NLC and drug nanocrystals). Up to 30 % of testosterone undecanoate could be incorporated into the lipid phase of the NLC. Furthermore, the production of particles with different lipids, which are supposed to promote lymphatic absorption and hence the bioavailability of the hormone. Drug nanocrystals of testosterone (T) and testosterone undecanoate (TU) were prepared with a mean size of about 470 nm (TU) and 860 nm (T). Also with this system, an enhanced lymphatic absorption was expected. The bioavailabilites of the developed NLC based drug delivery systems were all higher than the bioavailability of the product on the market when no additional lipid was supplied. This gives reason to believe, that the influence of co-administered food on the bioavailability of the systems is less pronounced than with Andriol Testocaps®. Based on the findings that lipid nanoparticles can improve oral bioavailability, the development of an omega-3 fatty acids nanoparticulate system (NLC) out of cheap fish oil was a logic step. The oral bioavailability of the omega-3 fatty acids is much higher than the one of TU (about 70 %). Through the use of NLC technology, the taste and smell is even more reduced. It was rather unexpected that we achieved to have a formulation that consisted of 70 % lipid phase (and 30 % water) but still was paste-like and easy to redisperse. This makes the use of the paste as an additive in food and beverages possible to better supply the patient with essential omega-3 fatty acids.

A tuberculose (TB) ainda se apresenta como desafio para a Saúde Pública, a nível global. Essa doença negligenciada (DN) tem como tratamento de primeira escolha a rifampicina. Esse fármaco pertence à classe II, segundo o Sistema de Classificação Biofarmacêutica (SCB), apresentando baixa solubilidade em água. Tal característica constitui desafio no desenvolvimento de formas farmacêuticas eficazes e seguras. O uso de nanotecnologia tem se destacado como alternativa promissora para melhorar a solubilidade aquosa de fármacos. Nesse sentido, o presente trabalho teve como objetivo a preparação e a caracterização físico-química de nanocristais de rifampicina. A preparação dos nanocristais foi realizada empregando método de moagem de alta energia, homogeneização a alta pressão e moagem via úmida em escala reduzida. Os resultados referentes ao método de moagem de alta energia (MAE) demostraram formação de nanocristais, mas em quantidade reduzida seguida da formação de agregados (F1-M, F2-M e F3-M). A homogeneização a alta pressão (HAP) permitiu a formação de nanocristais (F1-H e F2-H). A formulação F1-H contendo o poloxâmero 188 não apresentou estabilidade após 24 horas da preparação. A F2-H obteve diâmetro hidrodinâmico médio (DHM) de 412,60 ± 4,12 nm, índice de polidispersividade igual a 0,12 ± 0,02 e potencial zeta igual a -9,94 ± 0,19 mV. A elevada concentração requerida do agente estabilizante para essa formulação foi fator limitante para o seu desenvolvimento. A moagem via úmida em escala reduzida permitiu a formação de nanocristais de rifampicina F1-MU e F2-MU, com DHM igual a 340,20 ± 5,44 nm e 364,2 ± 4,50 nm, respectivamente, e distribuição de tamanho uniforme. A avaliação do DHM, do IP e do PZ, por período de três meses, revelou a estabilidade dessas formulações. Essas formulações foram obtidas por meio de planejamento de experimentos por superfície de resposta tendo como variáreis a concentração de rifampicina, a concentração do agente estabilizante e a quantidade de esferas de zircônia. As medidas de distribuição de tamanho médio das partículas e a morfologia foram realizadas utilizando difração a laser (LD) e microscopia eletrônica de transmissão (MET), respectivamente. Adicionalmente, as avaliações empregando calorimetria exploratória diferencial (DSC) e difração de raio X (DRX) revelaram que não houve mudança na estrutura cristalina do polimorfo II de rifampicina e nem interação entre o fármaco e os excipientes. O presente trabalho permitiu a obtenção de de nanocristais de rifampicina estáveis e com solubilidade maior de até 1,92 vezes (F1-MU) e 1,66 vezes (F2-MU), em água, quando comparada à rifampicina matéria-prima. Os perfis de dissolução das formulações F1-MU e F2-MU demonstraram dissolução de 95% de rifampicina em aproximadamente 5 minutos. Esse resultado é significativamente superior àquele observado para o produto FURP-rifampicina suspensão oral 20 mg/mL que apresentou dissolução de 23,2% nesse mesmo intervalo de tempo. A avaliação da atividade antimicrobiana das nanosuspensões foi confirmada frente à rifampicina padrão por meio da determinação da sua concentração mínima inibitória. / Tuberculosis (TB) still presents a challenge for public health globally. This Neglected Tropical Disease (NTDs) has as the treatment of choice rifampicin. This drug belongs to the class II, according to Biopharmaceutics Classification System (BCS), with low water solubility. This characteristic is a challenge in the development of safe and effective dosage forms. The nanotechnology has emerged as a promising alternative to improve the aqueous solubility of drugs. Accordingly, the present work aimed to the preparation and physicochemical characterization of nanocrystals of rifampicin. The preparation of the nanocrystals was performed using high-energy ball milling method, high-pressure homogenization and wet grinding process on a small scale. The results of the high-energy ball milling method demonstrated formation of nanocrystals, but in small amounts followed by the formation of aggregates (F1-M, F2-M and F3-M). The high pressure homogenization (HPH) allowed the formation of nanocrystals (F1-H and F2-H). F1-M formulation containing Poloxamer 188 did not show stability after 24 hours preparation. F2-H obtained mean hydrodynamic diameter (DHM) of 412.60 ± 4.12 nm, polydispersity index of 0.12 ± 0.02 and zeta potential of -9.94 ± 0.19 mV. The high concentration of stabilizing agent required for this formulation was a limiting factor for the development. The wet grinding process on a small scale allowed the formation of rifampicin nanocrystal F1-MU and F2-MU with DHM of 340,20 ± 5,44 nm e 364,2 ± 4,50, respectively, and size distribution uniform. The evaluation of DHM, IP and PZ, for three months, showed stability of these formulations. These formulations were obtained by design of experiments using response surface having as variables the concentration of rifampicin, the concentration of the stabilizing agent and the amount of zirconia beads. The mean size distribution measurements of particles and morphology were performed using laser diffraction (LD) and transmission electron microscopy (TEM), respectively. Additionally, the evaluations using differential scanning calorimetry (DSC) and X-ray diffraction (XRD) revealed that there was no change in the crystalline structure of polymorph II of rifampicin and no interaction between the drug and excipients. This study allowed obtaining stable rifampicin nanocrystals and greater solubility of up to 1.92 times (F1-MU) and 1.66 times (F2-MU) in water compared to rifampicin feedstock. The dissolution profiles of F1-MU and F2-MU formulations showed 95% dissolution of rifampicin in approximately 5 minutes. This result is significantly higher than that observed for the rifampicin-FURP oral suspension product 20 mg / ml that had Dissolving 23.2% over the same time interval. The evaluation of the antimicrobial activity of nanosuspensions was confirmed against the standard rifampicin by determining its minimum inhibitory concentration.

A tuberculose (TB) ainda se apresenta como desafio para a Saúde Pública, a nível global. Essa doença negligenciada (DN) tem como tratamento de primeira escolha a rifampicina. Esse fármaco pertence à classe II, segundo o Sistema de Classificação Biofarmacêutica (SCB), apresentando baixa solubilidade em água. Tal característica constitui desafio no desenvolvimento de formas farmacêuticas eficazes e seguras. O uso de nanotecnologia tem se destacado como alternativa promissora para melhorar a solubilidade aquosa de fármacos. Nesse sentido, o presente trabalho teve como objetivo a preparação e a caracterização físico-química de nanocristais de rifampicina. A preparação dos nanocristais foi realizada empregando método de moagem de alta energia, homogeneização a alta pressão e moagem via úmida em escala reduzida. Os resultados referentes ao método de moagem de alta energia (MAE) demostraram formação de nanocristais, mas em quantidade reduzida seguida da formação de agregados (F1-M, F2-M e F3-M). A homogeneização a alta pressão (HAP) permitiu a formação de nanocristais (F1-H e F2-H). A formulação F1-H contendo o poloxâmero 188 não apresentou estabilidade após 24 horas da preparação. A F2-H obteve diâmetro hidrodinâmico médio (DHM) de 412,60 ± 4,12 nm, índice de polidispersividade igual a 0,12 ± 0,02 e potencial zeta igual a -9,94 ± 0,19 mV. A elevada concentração requerida do agente estabilizante para essa formulação foi fator limitante para o seu desenvolvimento. A moagem via úmida em escala reduzida permitiu a formação de nanocristais de rifampicina F1-MU e F2-MU, com DHM igual a 340,20 ± 5,44 nm e 364,2 ± 4,50 nm, respectivamente, e distribuição de tamanho uniforme. A avaliação do DHM, do IP e do PZ, por período de três meses, revelou a estabilidade dessas formulações. Essas formulações foram obtidas por meio de planejamento de experimentos por superfície de resposta tendo como variáreis a concentração de rifampicina, a concentração do agente estabilizante e a quantidade de esferas de zircônia. As medidas de distribuição de tamanho médio das partículas e a morfologia foram realizadas utilizando difração a laser (LD) e microscopia eletrônica de transmissão (MET), respectivamente. Adicionalmente, as avaliações empregando calorimetria exploratória diferencial (DSC) e difração de raio X (DRX) revelaram que não houve mudança na estrutura cristalina do polimorfo II de rifampicina e nem interação entre o fármaco e os excipientes. O presente trabalho permitiu a obtenção de de nanocristais de rifampicina estáveis e com solubilidade maior de até 1,92 vezes (F1-MU) e 1,66 vezes (F2-MU), em água, quando comparada à rifampicina matéria-prima. Os perfis de dissolução das formulações F1-MU e F2-MU demonstraram dissolução de 95% de rifampicina em aproximadamente 5 minutos. Esse resultado é significativamente superior àquele observado para o produto FURP-rifampicina suspensão oral 20 mg/mL que apresentou dissolução de 23,2% nesse mesmo intervalo de tempo. A avaliação da atividade antimicrobiana das nanosuspensões foi confirmada frente à rifampicina padrão por meio da determinação da sua concentração mínima inibitória. / Tuberculosis (TB) still presents a challenge for public health globally. This Neglected Tropical Disease (NTDs) has as the treatment of choice rifampicin. This drug belongs to the class II, according to Biopharmaceutics Classification System (BCS), with low water solubility. This characteristic is a challenge in the development of safe and effective dosage forms. The nanotechnology has emerged as a promising alternative to improve the aqueous solubility of drugs. Accordingly, the present work aimed to the preparation and physicochemical characterization of nanocrystals of rifampicin. The preparation of the nanocrystals was performed using high-energy ball milling method, high-pressure homogenization and wet grinding process on a small scale. The results of the high-energy ball milling method demonstrated formation of nanocrystals, but in small amounts followed by the formation of aggregates (F1-M, F2-M and F3-M). The high pressure homogenization (HPH) allowed the formation of nanocrystals (F1-H and F2-H). F1-M formulation containing Poloxamer 188 did not show stability after 24 hours preparation. F2-H obtained mean hydrodynamic diameter (DHM) of 412.60 ± 4.12 nm, polydispersity index of 0.12 ± 0.02 and zeta potential of -9.94 ± 0.19 mV. The high concentration of stabilizing agent required for this formulation was a limiting factor for the development. The wet grinding process on a small scale allowed the formation of rifampicin nanocrystal F1-MU and F2-MU with DHM of 340,20 ± 5,44 nm e 364,2 ± 4,50, respectively, and size distribution uniform. The evaluation of DHM, IP and PZ, for three months, showed stability of these formulations. These formulations were obtained by design of experiments using response surface having as variables the concentration of rifampicin, the concentration of the stabilizing agent and the amount of zirconia beads. The mean size distribution measurements of particles and morphology were performed using laser diffraction (LD) and transmission electron microscopy (TEM), respectively. Additionally, the evaluations using differential scanning calorimetry (DSC) and X-ray diffraction (XRD) revealed that there was no change in the crystalline structure of polymorph II of rifampicin and no interaction between the drug and excipients. This study allowed obtaining stable rifampicin nanocrystals and greater solubility of up to 1.92 times (F1-MU) and 1.66 times (F2-MU) in water compared to rifampicin feedstock. The dissolution profiles of F1-MU and F2-MU formulations showed 95% dissolution of rifampicin in approximately 5 minutes. This result is significantly higher than that observed for the rifampicin-FURP oral suspension product 20 mg / ml that had Dissolving 23.2% over the same time interval. The evaluation of the antimicrobial activity of nanosuspensions was confirmed against the standard rifampicin by determining its minimum inhibitory concentration.

L'arsthinol est un organoarsénié qui a été utilisé dans les années 1950 dans le traitement de l'amibiase et en dermatologie (pian). Ce composé commercialisé sous le nom de Balarsen® était relativement bien toléré en clinique. Récemment, des essais in vitro ont montré que l'arsthinol était plus actif sur les cellules leucémiques (U937 et K562) que le trioxyde d'arsenic inorganique et le mélarsoprol. Dans notre travail, l'activité antileucémique de l'arsthinol a été évaluée sur les cellules NB4 de leucémie aiguë promyélocytaire (LAM3). Nous avons constaté que ce composé inhibait la croissance et induisait l'apoptose de ces cellules à des concentrations = 5µM. Cette activité sur les cellules NB4 est à peu près équivalente à celle obtenue avec le trioxyde d'arsenic. Nous avons par ailleurs mis au point des nanosuspensions d'arsthinol qui ont permis de diminuer considérablement les concentrations cérébrales en arsenic après injection I.V. chez la souris. A l'inverse, les concentrations d'arsenic dans la moelle osseuse sont restées importantes. De plus, l'arsthinol sous forme des nanosuspensions reste toujours actif sur les cellules NB4 de LAM3. En conséquence, cette distribution tissulaire des nanosuspensions d'arsthinol est plutôt avantageuse pour l'activité antileucémique de l'arsthinol. Enfin, nous avons identifié les métabolites de l'arsthinol dans l'urine de souris par CLHP-SM. Cette étude nous a permis de compléter la connaissance du métabolisme de l'arsthinol et de son élimination. / The organoarsenical arsthinol (Balarsen®) was used in the 1950s in the treatment of amoebiasis and in dermatology and was considered as ‘highly tolerated'. Recent investigations have shown a very good efficiency of arsthinol on leukemic cells (U937 and K562) as compared with arsenic trioxide and melarsoprol. In the present work, we have assessed the anti-leukemic activity of arsthinol on acute promyelocytic leukemia NB4 cells as compared with As2O3. Our results have shown that arsthinol and As2O3 induced growth inhibition and apoptosis at low concentrations = 5µM. Arsthinol is a promising drug for leukemia. However, this dithiarsolane is very poorly soluble in water. An alternative approach to overcoming problems such as solubility, local intolerability and risks of neurotoxicity is to develop nanosuspensions of the drug. The use of nanosuspensions of arsthinol after I.V. injection in mice has allowed us to reduce the cerebral concentration of the arsenical. In contrast, bone-marrow concentrations remained very high. Moreover, arsthinol nanosuspensions remained cytotoxic on NB4 cells. Finally, we have determined the metabolites of arsthinol in urine of mice. This study allowed us to complete the understanding on the mechanism of biotransformation and the elimination pathways of the drug.

The aim of this work is to develop an effective new MGA delivery system by means of nanotechnology for the treatment of leishmaniosis which could be administered by parenteral or oral route in a future. Moreover, for ensuring the effectiveness of the formulations developed, their in vitro activities will be assessed against L. infantum. The intention is to prepare a target drug delivery system by means of different technological strategies like micro-nanoparticles by spray drying. These formulations should target the antileishmanial drug to the macrophages which are the host cells of Leishmania parasites. If this purpose was achieved the drug bioavaibility would be increased, therefore lower doses could be administered, reducing the side effects and improving the efficiency of the treatment. The main objective can be summarized as to develop and characterize a new MGA formulation using nanotechnologies. It implies: 1. To study in vitro the effectiveness and cytotoxicity of formulations against Leishmania. 2. To develop preliminary in vitro uptake studies in macrophages using quantum dots assisted imaging.3. To study MGA release profile from the new delivery device developed.The present development of a new dosage form of MGA starts with the elaboration of emulsions, self-emulsifying drug delivery systems and nanosuspensions. However, the main part is centralized by the microencapsulation of MGA by spray drying using the preliminary studies as reference and the polymer chitosan as the main excipient. Spray drying technique has been used to elaborate two kinds of nano/microspheres, on one side those which come from emulsions and on the other side those which come from solutions. Both cases have been morphologically characterized and their effectiveness has been studied in vitro against Leishmania parasites. Moreover, the ability to be phagocyted by macrophages cells has been investigated using quantum dots assisted imaging in the Department of Pharmaceutical Sciences of the University of Connecticut during a stage.A new meglumine antimoniate delivery device for the treatment of leishmaniosis has been properly developed using spray drying technique achieving efficiencies of encapsulation higher than 90 % and process yields of 60 %. All the antimony IC50 values from encapsulated meglumine antimoniate in the chitosan microspheres tested against promastigotes and amastigotes are considerably lower compared to the mean value of IC50 in Glucantime® solution and give an Safety Index ratio higher than 1. Moreover, it is reported for the first time a novel in vitro activity of chitosan against L.infantum with a low cytotoxicity in macrophages assays (PATENEP P200700968). The uptake studies confirm the better suitability of chitosan as polymer to target drugs to macrophages compared to the commonly used PLGA.It has been shown that high percentages of chitosan in solutions to be spray-dried reduce the yield of the process, produce larger wrinkled microspheres but increase the efficiency of encapsulation. Chitosan microspheres exhibit a biphasic prolonged release for 24 h, characterized by an initial burst effect followed by slow release. High polymer ratios reduce the drug release in all the study. Moreover, high percentages of glutaraldehid in chitosan microspheres tend to increase significantly the presence of Non-Fickian drug release mechanism. These microspheres show the slowest release for the first 3 h but the highest percentage of drug released at 24 h. Moreover, they are among the more active microspheres against L.infantum. The minimum antimony IC50 value of chitosan microspheres is obtained using high percentages of glutaraldehid, low percentages of chitosan and low inlet temperatures. This new delivery system could offer a new pharmacological tool for treatment of leishmaniosis that reduces the doses required, lowering toxic side effects due to meglumine antimoniate.

Dados do Instituto Nacional do Câncer revelam 14,1 milhões de casos novos de câncer em 2012 em todo o mundo, e a estimativa para 2014/2015 no Brasil aponta para mais 500 mil novos casos. Assim, pesquisas voltadas à produção de nanopartículas e hidrogéis, constituídos de polímeros naturais ou sintéticos, são importantes para o desenvolvimento de sistemas destinados à liberação controlada de fármacos antitumorais. Nesse sentido, este estudo visou produzir derivados hidrofílicos de quitosanas, N,O-metoxi(polietilenoglicol)-g-quitosana, destinados ao encapsulamento e à liberação de fármacos antitumorais. As características estruturais e físico-químicas dos polímeros foram avaliadas por FTIR, RMN 1H, solubilidade em função do pH, viscosimetria, DRX e TGA. As quitosanas de partida, com diferentes graus médios de desacetilação e massas molares médias viscosimétricas, QD1x ( = 64,0 ± 1,1 % e = 495,6 ± 6,3.103 g mol-1), QD2x ( = 75,8 ± 0,8 % e = 346,8 ± 5,8.103 g mol-1) e QD3x ( = 92,3 ± 0,9 % e = 501,9 ± 5,9.103 g mol-1), produzidas pela aplicação do processo DAIUS à β-quitina, e quitosana comercial, Q ( = 94,7 ± 0,7 % e = 82,9 ± 2,0.103 g mol-1), foram avaliadas quanto aos teores de metais pesados por ICP OES e os resultados comparados aos limites permitidos pela ANVISA e Farmacopeia norte-americana. Teores significativos de metais foram detectados nas quitosanas QD1x, QD2x e QD3x (Ti e Al) e na quitosana comercial (Ni). O emprego de α-metoxipoli(etilenoglicol)-ω-carboxi possibilitou a síntese dos derivados PgQD1x, PgQD2x, PgQD3x e PgQ, que apresentaram graus médios de substituição semelhantes ( ≈ 40%). Os derivados foram hidrossolúveis em amplo intervalo de pH (1 – 11) e apresentaram viscosidades intrínsecas significativamente inferiores quando comparados às quitosanas. Foi observado que a estabilidade térmica e a cristalinidade das quitosanas são inferiores às de beta-quitina, enquanto os derivados exibiram maior cristalinidade e são termicamente mais estáveis quando comparados às quitosanas. Em geral, o aumento da razão molar –NH3+/TPP empregada na preparação das nano e microsuspensões de polímero/TPP pelo método de gelificação iônica resultou no aumento da densidade de cargas positivas nas superfícies das partículas. Entretanto, a ocorrência de numerosas cadeias de mPEG nos polímeros N,O-mPEG-g-quitosana levou à predominância das cadeias laterais hidrofílicas nas superfícies das partículas, blindando as cargas positivas, favorecendo a hidratação das partículas e o aumento dos diâmetros hidrodinâmicos médios. A influência das viscosidades intrínsecas dos polímeros e das concentrações poliméricas foi avaliada através do parâmetro de recobrimento (c[η]). Essa avaliação revelou que os diâmetros hidrodinâmicos médios das partículas são diretamente afetados por c[η] nos casos dos sistemas quitosana/TPP, enquanto as viscosidades intrínsecas dos derivados N,O-mPEG-g-quitosana são determinantes nos sistemas N,O-mPEG-g-quitosana/TPP. O estudo do comportamento reológico dos hidrogéis de N,O-mPEG-g-quitosana revelou que G’ > G’’ nos casos de PgQD3x, PgQD1x e PgQ, o que é característico de gel rígido, enquanto que no caso de PgQD2x foi observado G’’ > G’, indicando a predominância do comportamento viscoso sobre o elástico. O ponto de crossover foi observado acima de 38,2 ºC, indicando a formação de hidrogel estruturado termosensível. Assim, pesquisas futuras poderão investigar a influência das características estruturais e físico-químicas destes carreadores poliméricos, visando melhor eficiência de incorporação e liberação in vitro de fármacos antitumorais. / Data from National Institute of Cancer show an increase of 14.1 million new cases of cancer over the world in 2012, and the estimate for 2014/2015 in Brazil points to over 500,00 new cases. Thus, research focused on the production of nanoparticles and hydrogels, consisting by natural or synthetic polymers, are important for the development of systems for controlled release of antitumoral drugs. Therefore, this study aimed to produce systems based on hydrophilic derivative of chitosan, N,O-methoxy(polyethyleneglycol)-g-chitosan, for the encapsulation and release of antitumor drugs. The structural and physicochemical characteristics of the chitosan and the polymers were analyzed by FTIR, 1H NMR, solubility as function of pH, viscosimetry, XRD and TGA. The parent chitosan with different average degrees of deacetylation and viscosimetric average molecular weight, QD1x ( = 64,0 ± 1,1 % e = 495,6 ± 6,3.103 g mol-1), QD2x ( = 75,8 ± 0,8 % e = 346,8 ± 5,8.103 g mol-1) e QD3x ( = 92,3 ± 0,9 % e = 501,9 ± 5,9.103 g mol-1), produced applying the USAD to β-chitin, and the comercial chitosan, Q ( = 94,7 ± 0,7 % e = 82,9 ± 2,0.103 g mol-1) were analyzed for heavy metal content by ICP OES and the results compared to the limits allowed by ANVISA and US Pharmacopoeial. Significant levels of metals were detected in chitosan QD1x, QD2x and QD3x (Ti and Al) and commercial chitosan (Ni). The use of α-methoxypoly(ethyleneglycol)-ω-carboxy enabled the synthesis of derivatives PgQD1x, PgQD2x, PgQD3x and PgQ, which had similar average degree of substitution ( ≈ 40%). The derivatives were soluble in a broad pH range (1-11) and presented significantly lower intrinsic viscosities as compared to chitosan. It was observed that the thermal stability and crystallinity of chitosan are inferior to β-chitin, while the derivatives exhibit higher crystallinity and are more thermally stable as compared to chitosan. In general, increasing molar ratio of –NH3+/TPP in the preparation of nano- and microsuspensions of polymer/TPP by ionic gelation method, resulted in an increased positive charge density on the surfaces of the particles. However, the occurrence of a great number of chains of mPEG along the N,O-mPEG-g-chitosan chains led to the predominance of hydrophilic side chains on the surfaces of the particles, shielding the positive charges, favoring the hydration of the particles and the increasing the average hydrodynamic diameter. The influence of the intrinsic viscosities of the polymers and polymer concentrations were evaluated by the overlapping parameter (c[η]). This assessment revealed that the average hydrodynamic diameter of the particles are directly affected by c[η] in the case of chitosan/TPP systems, while the intrinsic viscosities of the derivates N,O-mPEG-g-chitosan are essential for N,O-mPEG-g-chitosan/TPP systems. The study of the rheological behavior of the hydrogels of N,O-mPEG-g-chitosan revealed that G’ > G’’ in the case of PgQD3x, PgQD1x and PGQ which is characteristic of structured gel, whereas in the case of PgQD2x it was observed G’’ > G’ indicating the predominance of the viscous behavior over the elastic. The crossover point was observed above 38.2 °C, indicating the formation of structured thermosensitive hydrogel. Thus, future research will investigate the influence of structural and physicochemical characteristics of polymeric carriers, aiming a better incorporation and release in vitro efficiency of antitumor drugs.

Dados do Instituto Nacional do Câncer revelam 14,1 milhões de casos novos de câncer em 2012 em todo o mundo, e a estimativa para 2014/2015 no Brasil aponta para mais 500 mil novos casos. Assim, pesquisas voltadas à produção de nanopartículas e hidrogéis, constituídos de polímeros naturais ou sintéticos, são importantes para o desenvolvimento de sistemas destinados à liberação controlada de fármacos antitumorais. Nesse sentido, este estudo visou produzir derivados hidrofílicos de quitosanas, N,O-metoxi(polietilenoglicol)-g-quitosana, destinados ao encapsulamento e à liberação de fármacos antitumorais. As características estruturais e físico-químicas dos polímeros foram avaliadas por FTIR, RMN 1H, solubilidade em função do pH, viscosimetria, DRX e TGA. As quitosanas de partida, com diferentes graus médios de desacetilação e massas molares médias viscosimétricas, QD1x ( = 64,0 ± 1,1 % e = 495,6 ± 6,3.103 g mol-1), QD2x ( = 75,8 ± 0,8 % e = 346,8 ± 5,8.103 g mol-1) e QD3x ( = 92,3 ± 0,9 % e = 501,9 ± 5,9.103 g mol-1), produzidas pela aplicação do processo DAIUS à β-quitina, e quitosana comercial, Q ( = 94,7 ± 0,7 % e = 82,9 ± 2,0.103 g mol-1), foram avaliadas quanto aos teores de metais pesados por ICP OES e os resultados comparados aos limites permitidos pela ANVISA e Farmacopeia norte-americana. Teores significativos de metais foram detectados nas quitosanas QD1x, QD2x e QD3x (Ti e Al) e na quitosana comercial (Ni). O emprego de α-metoxipoli(etilenoglicol)-ω-carboxi possibilitou a síntese dos derivados PgQD1x, PgQD2x, PgQD3x e PgQ, que apresentaram graus médios de substituição semelhantes ( ≈ 40%). Os derivados foram hidrossolúveis em amplo intervalo de pH (1 – 11) e apresentaram viscosidades intrínsecas significativamente inferiores quando comparados às quitosanas. Foi observado que a estabilidade térmica e a cristalinidade das quitosanas são inferiores às de beta-quitina, enquanto os derivados exibiram maior cristalinidade e são termicamente mais estáveis quando comparados às quitosanas. Em geral, o aumento da razão molar –NH3+/TPP empregada na preparação das nano e microsuspensões de polímero/TPP pelo método de gelificação iônica resultou no aumento da densidade de cargas positivas nas superfícies das partículas. Entretanto, a ocorrência de numerosas cadeias de mPEG nos polímeros N,O-mPEG-g-quitosana levou à predominância das cadeias laterais hidrofílicas nas superfícies das partículas, blindando as cargas positivas, favorecendo a hidratação das partículas e o aumento dos diâmetros hidrodinâmicos médios. A influência das viscosidades intrínsecas dos polímeros e das concentrações poliméricas foi avaliada através do parâmetro de recobrimento (c[η]). Essa avaliação revelou que os diâmetros hidrodinâmicos médios das partículas são diretamente afetados por c[η] nos casos dos sistemas quitosana/TPP, enquanto as viscosidades intrínsecas dos derivados N,O-mPEG-g-quitosana são determinantes nos sistemas N,O-mPEG-g-quitosana/TPP. O estudo do comportamento reológico dos hidrogéis de N,O-mPEG-g-quitosana revelou que G’ > G’’ nos casos de PgQD3x, PgQD1x e PgQ, o que é característico de gel rígido, enquanto que no caso de PgQD2x foi observado G’’ > G’, indicando a predominância do comportamento viscoso sobre o elástico. O ponto de crossover foi observado acima de 38,2 ºC, indicando a formação de hidrogel estruturado termosensível. Assim, pesquisas futuras poderão investigar a influência das características estruturais e físico-químicas destes carreadores poliméricos, visando melhor eficiência de incorporação e liberação in vitro de fármacos antitumorais. / Data from National Institute of Cancer show an increase of 14.1 million new cases of cancer over the world in 2012, and the estimate for 2014/2015 in Brazil points to over 500,00 new cases. Thus, research focused on the production of nanoparticles and hydrogels, consisting by natural or synthetic polymers, are important for the development of systems for controlled release of antitumoral drugs. Therefore, this study aimed to produce systems based on hydrophilic derivative of chitosan, N,O-methoxy(polyethyleneglycol)-g-chitosan, for the encapsulation and release of antitumor drugs. The structural and physicochemical characteristics of the chitosan and the polymers were analyzed by FTIR, 1H NMR, solubility as function of pH, viscosimetry, XRD and TGA. The parent chitosan with different average degrees of deacetylation and viscosimetric average molecular weight, QD1x ( = 64,0 ± 1,1 % e = 495,6 ± 6,3.103 g mol-1), QD2x ( = 75,8 ± 0,8 % e = 346,8 ± 5,8.103 g mol-1) e QD3x ( = 92,3 ± 0,9 % e = 501,9 ± 5,9.103 g mol-1), produced applying the USAD to β-chitin, and the comercial chitosan, Q ( = 94,7 ± 0,7 % e = 82,9 ± 2,0.103 g mol-1) were analyzed for heavy metal content by ICP OES and the results compared to the limits allowed by ANVISA and US Pharmacopoeial. Significant levels of metals were detected in chitosan QD1x, QD2x and QD3x (Ti and Al) and commercial chitosan (Ni). The use of α-methoxypoly(ethyleneglycol)-ω-carboxy enabled the synthesis of derivatives PgQD1x, PgQD2x, PgQD3x and PgQ, which had similar average degree of substitution ( ≈ 40%). The derivatives were soluble in a broad pH range (1-11) and presented significantly lower intrinsic viscosities as compared to chitosan. It was observed that the thermal stability and crystallinity of chitosan are inferior to β-chitin, while the derivatives exhibit higher crystallinity and are more thermally stable as compared to chitosan. In general, increasing molar ratio of –NH3+/TPP in the preparation of nano- and microsuspensions of polymer/TPP by ionic gelation method, resulted in an increased positive charge density on the surfaces of the particles. However, the occurrence of a great number of chains of mPEG along the N,O-mPEG-g-chitosan chains led to the predominance of hydrophilic side chains on the surfaces of the particles, shielding the positive charges, favoring the hydration of the particles and the increasing the average hydrodynamic diameter. The influence of the intrinsic viscosities of the polymers and polymer concentrations were evaluated by the overlapping parameter (c[η]). This assessment revealed that the average hydrodynamic diameter of the particles are directly affected by c[η] in the case of chitosan/TPP systems, while the intrinsic viscosities of the derivates N,O-mPEG-g-chitosan are essential for N,O-mPEG-g-chitosan/TPP systems. The study of the rheological behavior of the hydrogels of N,O-mPEG-g-chitosan revealed that G’ > G’’ in the case of PgQD3x, PgQD1x and PGQ which is characteristic of structured gel, whereas in the case of PgQD2x it was observed G’’ > G’ indicating the predominance of the viscous behavior over the elastic. The crossover point was observed above 38.2 °C, indicating the formation of structured thermosensitive hydrogel. Thus, future research will investigate the influence of structural and physicochemical characteristics of polymeric carriers, aiming a better incorporation and release in vitro efficiency of antitumor drugs.

La réduction de la taille des particules jusqu’à l’obtention de nanocristaux est l’une des approches utilisées afin d’améliorer la pénétration cutanée des médicaments à usage topique. Nous proposons que la fabrication d’une formulation semi solide (hydrogel) à base de nanosuspension de docosanol, aboutira à une diffusion du principe actif supérieure à celle du produit commercial Abreva®, à travers des membranes synthétiques de polycarbonates. Le broyage humide est la technique proposée pour la production des nanoparticules de docosanol. Nous proposons aussi la préparation d’une formulation semi-solide (hydrogel) à usage topique à partir de la nanosuspension de docosanol. La nanosuspension de docosanol est obtenue par dispersion du docosanol en solution aqueuse en présence du polymère stabilisant hydroxypropylcellulose (HPC) et du surfactant laurylsulfate de sodium (SDS) suivi d’un broyage humide à faible ou à haute énergie. L’hydrogel de docosanol nanoformulé est préparé à l’aide de la nanosuspension de docosanol qui subit une gélification par le carbopol Ultrez 21 sous agitation mécanique suivie d’une neutralisation au triéthanolamine TEA. La taille des particules de la nanosuspension et de l’hydrogel a été déterminée par diffusion dynamique de la lumière (DLS). Une méthode analytique de chromatographie liquide à haute performance (HPLC) munie d’un détecteur évaporatif (ELSD) a été développée et validée pour évaluer la teneur de docosanol dans les préparations liquides, dans les différentes nanosuspensions et dans les hydrogels de docosanol. L’état de cristallinité des nanocristaux dans la nanosuspension et dans l’hydrogel a été étudié par calorimétrie différentielle à balayage. La morphologie de la nanosuspension et de l’hydrogel de docosanol a été examinée par microscopie électronique à balayage (MEB). Les propriétés rhéologiques et de stabilité physique à différentes températures ont été aussi étudiées pour la formulation semi-solide (hydrogel). De même, la libération in vitro du docosanol contenu dans l’hydrogel et dans le produit commercial Abreva® a été étudiée à travers deux membranes de polycarbonates de taille de pores 400 et 800 nm. Dans le cas de nanosuspensions, des cristaux de docosanol de taille nanométrique ont été produits avec succès par broyage humide. Les nanoparticules de tailles variant de 197 nm à 312 nm ont été produites pour des pourcentages différents en docosanol, en polymère HPC et en surfactant SDS. Après lyophilisation, une augmentation de la taille dépendant de la composition de la formulation a été observée tout en restant dans la gamme nanométrique pour la totalité presque des formulations étudiées. Dans le cas des hydrogels examinés, la taille moyenne des particules de docosanol est maintenue dans la gamme nanométrique avant et après lyophilisation. L’analyse thermique des mélanges physiques, des nanosuspensions et des hydrogels de docosanol a révélé la conservation de l’état de cristallinité des nanocristaux de docosanol après broyage et aussi après gélification. L’examen par microscopie électronique à balayage (MEB) a montré que la nanosuspension et l’hydrogel ont tous deux une morphologie régulière et les nanoparticules ont une forme sphérique. De plus les nanoparticules de la nanosuspension ont presque la même taille inférieure à 300 nm en accord avec le résultat obtenu par diffusion dynamique de la lumière (DLS). Les nanoparticules de l’hydrogel ont une légère augmentation de taille par rapport à celle de la nanosuspension, ce qui est en accord avec les mesures de DLS. D’après les mesures rhéologiques, l’hydrogel de docosanol a un comportement pseudoplastique et un faible degré de thixotropie. L’étude de stabilité physique a montré que les formulations d’hydrogel sont stables à basse température (5°C) et à température ambiante (21°C) pendant une période d’incubation de 13 semaines et instable au-delà de 30°C après deux semaines. La méthode HPLC-ELSD a révélé des teneurs en docosanol comprises entre 90% et 110% dans le cas des nanosuspensions et aux alentours de 100% dans le cas de l’hydrogel. L’essai de diffusion in vitro a montré qu’il y a diffusion de docosanol de l’hydrogel à travers les membranes de polycarbonates, qui est plus marquée pour celle de pore 800 nm, tandis que celui du produit commercial Abreva® ne diffuse pas. Le broyage humide est une technique bien adaptée pour la préparation des nanosuspensions docosanol. Ces nanosuspensions peuvent être utilisée comme base pour la préparation de l’hydrogel de docosanol nanoformulé. / Reducing the particle size to nanocrystals is one of the approaches used to improve the percutaneous penetration of topical dosage form. We propose that the preparation of a semi solid formulation of docosanol, can lead to higher diffusion of docosanol than in commercial product Abreva® through polycarbonate membranes. Wet ball milling is the proposed technique for docosanol nanoparticles preparation. We propose also the preparation of topical semi-solid formulation from docosanol nanosuspension. Docosanol nanosuspension is obtained from docosanol dispersion in aqueous solution in presence of the stabilizer polymer hydroxypropylcellulose (HPC) and the surfactant sodium laurylsulfate (SDS) followed by wet ball milling at low or high energy. Nanoformulated hydrogel of docosanol is prepared from docosanol nanosuspension which is gellified by carbopol Ultrez 21 under vigorous stirring followed by neutralization with triethanolamine TEA. Nanosuspension and hydrogel particle size was characterized by dynamic light scattering. An analytical method of high performance liquid chromatography (HPLC) with an evaporative detector (ELSD) has been developed and validated for docosanol content quantification in liquid preparation, in different nanosuspensions and in docosanol hydrogels. The crystalline state of nanosuspension and hydrogel nanocrystals was studied by scanning differential calorimetry (DSC). The morphology of nanosuspension and hydrogel was evaluated by Scanning electronic microscopy SEM. Rheological properties and physical stability at different temperatures were studied for semi-solid formulation. In vitro docosanol release from hydrogel and from the commercial product Abreva® was studied through two polycarbonate membranes of pore size 400 and 800 nm. In nanosuspensions, nanosized crystals of docosanol have been successfully produced by wet ball milling. Nanoparticles of size ranged from 197 nm to 312 nm could be obtained by percentage variation of docosanol, of polymer HPC and surfactant SDS. After freeze drying, an increase in size relative to formulation composition was observed but the size particle is in nanometric range for almost all studied formulations. In case of prepared hydrogels, mean particle size of docosanol is maintained in nanometric range before and after freeze drying. Thermal analysis of physical mixtures, docosanol nanosuspensions and hydrogels showed that crystalline structure of docosanol nanocrystals was conserved after milling and after hydrogel preparation. The SEM exam showed that the nanosuspension and hydrogel has similar regular crystal morphology and nanoparticles shape is spherical. Nanosuspension particles have almost the same particle size, less than 300 nm in agreement with DLS result. Hydrogel size particle showed a slight increase comparing to nanosuspension’s one which is in agreement with DLS result. Up to rheological measurement, docosanol hydrogel has a pseudoplastic behavior and small thixotropic degree. Physical stability study showed that the hydrogel is stable at 5 °C and 21°C during 13 weeks and instable above 30°C after two weeks. HPLC-ELSD determined that docosanol content is in the acceptance limit range [90% to 110%] for docosanol nanosuspension and close to 100% in docosanol hydrogel. In vitro diffusion test revealed that docosanol nanoparticles were diffused from hydrogel through polycarbonates membranes that was greater for the 800 nm pore membrane, while the commercial product Abreva® does not diffuse through any of the membranes (400 nm and 800 nm). Wet ball milling is a great technique for docosanol nanosuspension preparation. Nanosuspensions can be used as base for the preparation of semi-solid nanoformulation of docosanol.

La réduction de la taille des particules jusqu’à l’obtention de nanocristaux est l’une des approches utilisées afin d’améliorer la pénétration cutanée des médicaments à usage topique. Nous proposons que la fabrication d’une formulation semi solide (hydrogel) à base de nanosuspension de docosanol, aboutira à une diffusion du principe actif supérieure à celle du produit commercial Abreva®, à travers des membranes synthétiques de polycarbonates. Le broyage humide est la technique proposée pour la production des nanoparticules de docosanol. Nous proposons aussi la préparation d’une formulation semi-solide (hydrogel) à usage topique à partir de la nanosuspension de docosanol. La nanosuspension de docosanol est obtenue par dispersion du docosanol en solution aqueuse en présence du polymère stabilisant hydroxypropylcellulose (HPC) et du surfactant laurylsulfate de sodium (SDS) suivi d’un broyage humide à faible ou à haute énergie. L’hydrogel de docosanol nanoformulé est préparé à l’aide de la nanosuspension de docosanol qui subit une gélification par le carbopol Ultrez 21 sous agitation mécanique suivie d’une neutralisation au triéthanolamine TEA. La taille des particules de la nanosuspension et de l’hydrogel a été déterminée par diffusion dynamique de la lumière (DLS). Une méthode analytique de chromatographie liquide à haute performance (HPLC) munie d’un détecteur évaporatif (ELSD) a été développée et validée pour évaluer la teneur de docosanol dans les préparations liquides, dans les différentes nanosuspensions et dans les hydrogels de docosanol. L’état de cristallinité des nanocristaux dans la nanosuspension et dans l’hydrogel a été étudié par calorimétrie différentielle à balayage. La morphologie de la nanosuspension et de l’hydrogel de docosanol a été examinée par microscopie électronique à balayage (MEB). Les propriétés rhéologiques et de stabilité physique à différentes températures ont été aussi étudiées pour la formulation semi-solide (hydrogel). De même, la libération in vitro du docosanol contenu dans l’hydrogel et dans le produit commercial Abreva® a été étudiée à travers deux membranes de polycarbonates de taille de pores 400 et 800 nm. Dans le cas de nanosuspensions, des cristaux de docosanol de taille nanométrique ont été produits avec succès par broyage humide. Les nanoparticules de tailles variant de 197 nm à 312 nm ont été produites pour des pourcentages différents en docosanol, en polymère HPC et en surfactant SDS. Après lyophilisation, une augmentation de la taille dépendant de la composition de la formulation a été observée tout en restant dans la gamme nanométrique pour la totalité presque des formulations étudiées. Dans le cas des hydrogels examinés, la taille moyenne des particules de docosanol est maintenue dans la gamme nanométrique avant et après lyophilisation. L’analyse thermique des mélanges physiques, des nanosuspensions et des hydrogels de docosanol a révélé la conservation de l’état de cristallinité des nanocristaux de docosanol après broyage et aussi après gélification. L’examen par microscopie électronique à balayage (MEB) a montré que la nanosuspension et l’hydrogel ont tous deux une morphologie régulière et les nanoparticules ont une forme sphérique. De plus les nanoparticules de la nanosuspension ont presque la même taille inférieure à 300 nm en accord avec le résultat obtenu par diffusion dynamique de la lumière (DLS). Les nanoparticules de l’hydrogel ont une légère augmentation de taille par rapport à celle de la nanosuspension, ce qui est en accord avec les mesures de DLS. D’après les mesures rhéologiques, l’hydrogel de docosanol a un comportement pseudoplastique et un faible degré de thixotropie. L’étude de stabilité physique a montré que les formulations d’hydrogel sont stables à basse température (5°C) et à température ambiante (21°C) pendant une période d’incubation de 13 semaines et instable au-delà de 30°C après deux semaines. La méthode HPLC-ELSD a révélé des teneurs en docosanol comprises entre 90% et 110% dans le cas des nanosuspensions et aux alentours de 100% dans le cas de l’hydrogel. L’essai de diffusion in vitro a montré qu’il y a diffusion de docosanol de l’hydrogel à travers les membranes de polycarbonates, qui est plus marquée pour celle de pore 800 nm, tandis que celui du produit commercial Abreva® ne diffuse pas. Le broyage humide est une technique bien adaptée pour la préparation des nanosuspensions docosanol. Ces nanosuspensions peuvent être utilisée comme base pour la préparation de l’hydrogel de docosanol nanoformulé. / Reducing the particle size to nanocrystals is one of the approaches used to improve the percutaneous penetration of topical dosage form. We propose that the preparation of a semi solid formulation of docosanol, can lead to higher diffusion of docosanol than in commercial product Abreva® through polycarbonate membranes. Wet ball milling is the proposed technique for docosanol nanoparticles preparation. We propose also the preparation of topical semi-solid formulation from docosanol nanosuspension. Docosanol nanosuspension is obtained from docosanol dispersion in aqueous solution in presence of the stabilizer polymer hydroxypropylcellulose (HPC) and the surfactant sodium laurylsulfate (SDS) followed by wet ball milling at low or high energy. Nanoformulated hydrogel of docosanol is prepared from docosanol nanosuspension which is gellified by carbopol Ultrez 21 under vigorous stirring followed by neutralization with triethanolamine TEA. Nanosuspension and hydrogel particle size was characterized by dynamic light scattering. An analytical method of high performance liquid chromatography (HPLC) with an evaporative detector (ELSD) has been developed and validated for docosanol content quantification in liquid preparation, in different nanosuspensions and in docosanol hydrogels. The crystalline state of nanosuspension and hydrogel nanocrystals was studied by scanning differential calorimetry (DSC). The morphology of nanosuspension and hydrogel was evaluated by Scanning electronic microscopy SEM. Rheological properties and physical stability at different temperatures were studied for semi-solid formulation. In vitro docosanol release from hydrogel and from the commercial product Abreva® was studied through two polycarbonate membranes of pore size 400 and 800 nm. In nanosuspensions, nanosized crystals of docosanol have been successfully produced by wet ball milling. Nanoparticles of size ranged from 197 nm to 312 nm could be obtained by percentage variation of docosanol, of polymer HPC and surfactant SDS. After freeze drying, an increase in size relative to formulation composition was observed but the size particle is in nanometric range for almost all studied formulations. In case of prepared hydrogels, mean particle size of docosanol is maintained in nanometric range before and after freeze drying. Thermal analysis of physical mixtures, docosanol nanosuspensions and hydrogels showed that crystalline structure of docosanol nanocrystals was conserved after milling and after hydrogel preparation. The SEM exam showed that the nanosuspension and hydrogel has similar regular crystal morphology and nanoparticles shape is spherical. Nanosuspension particles have almost the same particle size, less than 300 nm in agreement with DLS result. Hydrogel size particle showed a slight increase comparing to nanosuspension’s one which is in agreement with DLS result. Up to rheological measurement, docosanol hydrogel has a pseudoplastic behavior and small thixotropic degree. Physical stability study showed that the hydrogel is stable at 5 °C and 21°C during 13 weeks and instable above 30°C after two weeks. HPLC-ELSD determined that docosanol content is in the acceptance limit range [90% to 110%] for docosanol nanosuspension and close to 100% in docosanol hydrogel. In vitro diffusion test revealed that docosanol nanoparticles were diffused from hydrogel through polycarbonates membranes that was greater for the 800 nm pore membrane, while the commercial product Abreva® does not diffuse through any of the membranes (400 nm and 800 nm). Wet ball milling is a great technique for docosanol nanosuspension preparation. Nanosuspensions can be used as base for the preparation of semi-solid nanoformulation of docosanol.