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- Intranasal delivery of nanostructured lipid carriers, solid lipid nanoparticles and nanoemulsions: a current overview of in vivo studiesPublication . Costa, Cláudia Pina; Moreira, João Nuno; Lobo, José Manuel Sousa; Silva, Ana CatarinaThe management of the central nervous system (CNS) disorders is challenging, due to the need of drugs to cross the blood‒brain barrier (BBB) and reach the brain. Among the various strategies that have been studied to circumvent this challenge, the use of the intranasal route to transport drugs from the nose directly to the brain has been showing promising results. In addition, the encapsulation of the drugs in lipid-based nanocarriers, such as solid lipid nanoparticles (SLNs), nanostructured lipid carriers (NLCs) or nanoemulsions (NEs), can improve nose-to-brain transport by increasing the bioavailability and site-specific delivery. This review provides the state-of-the-art of in vivo studies with lipid-based nanocarriers (SLNs, NLCs and NEs) for nose-to-brain delivery. Based on the literature available from the past two years, we present an insight into the different mechanisms that drugs can follow to reach the brain after intranasal administration. The results of pharmacokinetic and pharmacodynamics studies are reported and a critical analysis of the differences between the anatomy of the nasal cavity of the different animal species used in in vivo studies is carried out. Although the exact mechanism of drug transport from the nose to the brain is not fully understood and its effectiveness in humans is unclear, it appears that the intranasal route together with the use of NLCs, SLNs or NEs is advantageous for targeting drugs to the brain. These systems have been shown to be more effective for nose-to-brain delivery than other routes or formulations with non-encapsulated drugs, so they are expected to be approved by regulatory authorities in the coming years.
- Thermosensitive nasal in situ gels of lipid-based nanosystems to improve the treatment of Alzheimer’s DiseasePublication . Cunha, Sara; Forbes, Ben; Lobo, José Manuel Sousa; Silva, Ana CatarinaThermosensitive in situ gels are promising formulations for the management of Alzheimer’s disease (AD), since they increase the residence time of lipid-based nanosystems in the nasal cavity, improving drug therapeutic efficacy. The purpose of this study is to prepare thermosensitive in situ gels with anticholinesterase inhibitor (RVG)-loaded nanostructured lipid carriers (NLC) and nanoemulsions to improve the residence time of the formulations in the nasal cavity. Different concentrations of thermosensitive polymers were added to the RVG-loaded NLC and to the RVG-loaded nanoemulsion to optimize the gelation temperature of the in situ gels; concentrations of 17% (%, w/w) of Kolliphor® P407 and 0.3% (%, w/w) of MethocelTM K4M were selected. The in situ gels of the RVG-loaded NLC and RVG-loaded nanoemulsion had a particle size, PDI, ZP, and pH of, respectively: 141.70 ± 0.40 nm and 146.10 ± 1.73 nm; 0.45 ± 0.00 and 0.43 ± 0.02; −4.06 ± 1.03 mV and −4.09 ± 0.71 mV, 6.60 ± 0.01 and 7.00 ± 0.02. In addition, these in situ gels showed a non-Newtonian plastic behavior, and the texture parameters presented desirable values for nasal administration. From these results, we concluded that the developed in situ gels can be used to improve the treatment of AD through the nose-to-brain route.
- Hematopoietic growth factorsPublication . Silva, Ana Catarina; Moreira, João Nuno; Lobo, José Manuel Sousa
- Current applications of pharmaceutical biotechnologyPublication . Silva, Ana Catarina; Moreira, João Nuno; Lobo, José Manuel Sousa; Almeida, HugoThis book offers an authoritative review of biopharmaceuticals and their clinical relevance. Biopharmaceuticals have been showing high therapeutic potential by means of biological and biosimilar medicines, particularly for the treatment of cancer, chronic diseases (e.g. diabetes, Crohn's disease, psoriasis and rheumatoid arthritis), neurodegenerative disorders (e.g. multiple sclerosis), and they have also been contributing to the progress of innovative therapies such as assisted reproductive medicine. Since the eighties, several biopharmaceuticals have been approved and, due to patents expiration, many biosimilars are also marketed. In this book, readers will find the most relevant updated information about the main clinical applications of pharmaceutical biotechnology. The authors provide expert analysis about the industrial challenges of recombinant proteins and the different classes of biopharmaceuticals, including monoclonal antibodies, vaccines, growth factors and stem cells. Topics such as bioprinting technologies in tissue engineering, gene therapy and personalized medicine are also covered in this book. Professionals, students and researchers interested in this field will find this work an important account.
- Preparações vaginais: ontem, hoje e amanhãPublication . Silva, Ana Catarina; Lobo, José Manuel Sousa; Correia, Armanda do CarmoAs preparações farmacêuticas para aplicação vaginal são usadas desde a Antiguidade para tratar afeções vaginais. A atuação local de fármacos administrados na vagina promove a eficácia dos tratamentos e diminui possíveis efeitos tóxicos. Além disso, algumas moléculas pequenas e lipófilas conseguem permear a parede vaginal, sendo absorvidas para a corrente circulatória. A possibilidade de absorção sistémica através da vagina destaca-a como uma alternativa à via oral, com vantagens como o facto de evitar a primeira passagem hepática e os efeitos adversos gastrintestinais que se verificam com alguns fármacos. As formas farmacêuticas de libertação modificada permitem melhorar alguns aspetos da farmacocinética dos fármacos e tornam as administrações menos frequentes, o que promove a adesão à terapêutica e, consequentemente, a eficácia. As estratégias de libertação modificada para a via vaginal incluem sistemas de libertação, como anéis ou películas vaginais, sistemas mucoadesivos e nanossistemas. Novas possibilidades terapêuticas adequadas a esta via têm surgido, das quais se destacam a administração de microbicidas para prevenção da transmissão do virus da imunodeficiência humana e a administração de biofármacos, incluindo vacinas e anticorpos monoclonais com propriedades espermicidas, antivíricas e antifúngicas.
- Using the quality by design (QbD) approach to optimize formulations of lipid nanoparticles and nanoemulsions: a reviewPublication . Cunha, Sara; Costa, Cláudia Pina; Moreira, João Nuno; Lobo, José Manuel Sousa; Silva, Ana CatarinaQuality-by-design (QbD) approach has been applied to optimize lipid-based nanosystems formulations, including solid lipid nanoparticles (SLN), nanostructured lipid carriers (NLC) and nanoemulsions, besides being increasingly requested by regulatory authorities. Different mathematical models and statistical tests have been used, with similar conclusions regarding the parameters that influence the physical features of the resulting nanosystems. These include, variations in composition (e.g. lipid(s) and/or emulsifier(s)) and manufacturing parameters (e.g. emulsification rate and/or time, sonication amplitude and/or time, and homogenization pressure and/or cycles). These are critical parameters that influence nanoparticle/globule mean size, polydispersity index, zeta potential, drug encapsulation efficiency and in vitro drug release. This review addresses the concepts and applications of QbD for the development of lipid-based nanosystems, reporting successful examples published in the last 2 years. Although, some limitations have been identified, it is expected that in the upcoming years the application of QbD in pharmaceutical development will be an established approach.
- Application of the Quality-by-Design (QbD) approach to improve the nose-to-brain delivery of diazepam-loaded Nanostructured Lipid Carriers (NLCs)Publication . Costa, Cláudia Pina; Cunha, Sara; Peixoto, Andreia F.; Moreira, João Nuno; Lobo, José Manuel Sousa; Silva, Ana CatarinaThe intranasal administration of nanostructured lipid carriers (NLCs) has been suggested as a promising strategy to improve the fast treatment of epilepsy. This route allows for drug passage directly from the nose to the brain, avoiding the need of bypassing the blood–brain barrier. In addition, the quality-by-design (QbD) approach is a useful tool for the optimization of manufacturing variables, resulting in effective and safe pharmaceutical formulations. The aim of this work was to use the QbD approach to optimize a NLCs formulation for the nose-to-brain delivery of diazepam. The studies began with the screening of excipients and the assessment of the lipid-drug compatibility. The central composite design was used to evaluate the effects of critical material attributes (CMAs) (ratio of solid and liquid lipids and the amount of drug and emulsifiers) on the CQAs of the diazepam-loaded NLCs formulation (particle size, polydispersity index (PDI), zeta potential (ZP) and encapsulation efficiency (EE)). The results showed that the most adequate ratios of lipids and emulsifiers were 6.65:2.85 and 4.2:0.3 (%, w/w), with values of 84.92 nm, 0.18, −18.20 mV and 95.48% for particle size, PDI, ZP and EE, respectively. This formulation was selected for further studies related to the optimization of critical process parameters (CPPs).