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Daniela Lopes-de-Campos,1,* Rita M Pinto,1,* Sofia A Costa Lima,1 Tiago Santos,2,3 Bruno Sarmento,2–4 Cláudia Nunes,1 Salette Reis1 1LAQV, REQUIMTE, Departamento de Ciáncias Químicas, Faculdade de Farmácia, Universidade do Porto, Porto, Portugal; 2INEB – Instituto de Engenharia Biomédica, Universidade do Porto, Porto, Portugal; 3i3S – Instituto de Investigação e Inovação em Saúde, Universidade do Porto, Porto, Portugal; 4IINFACTS, Instituto de Investigação e Formação Avançada em Ciências e Tecnologias da Saúde, Instituto Universitário de Ciências da Saúde, Gandra, Portugal *These authors contributed equally to this work Purpose: Amoxicillin is a commonly used antibiotic, although degraded by the acidic pH of the stomach. This is an important limitation for the treatment of Helicobacter pylori infections. The purpose of this work was to encapsulate amoxicillin in lipid nanoparticles, increasing the retention time at the site of infection (gastric mucosa), while protecting the drug from the harsh conditions of the stomach lumen.Materials and methods: The nanoparticles were produced by the double emulsion technique and optimized by a three-level Box-Behnken design. Tween 80 and linolenic acid were used as potential therapeutic adjuvants and dioleoylphosphatidylethanolamine as a targeting agent to Helicobacter pylori. Nanoparticles were characterized regarding their physico-chemical features, their storage stability, and their usability for oral administration (assessment of in vitro release, in vitro cell viability, permeability, and interaction with mucins).Results: The nanoparticles were stable for at least 6 months at 4°C. In vitro release studies revealed a high resistance to harsh conditions, including acidic pH and physiologic temperature. The nanoparticles have a low cytotoxicity effect in both fibroblasts and gastric cell lines, and they have the potential to be retained at the gastric mucosa.Conclusion: Overall, the designed formulations present suitable physico-chemical features for being henceforward used by oral administration to treat Helicobacter pylori infections. Keywords: linolenic acid, dioleoylphosphatidylethanolamine, Box-Behnken design, permeability, mucins, Helicobacter pylori

Iúri Frias, Ana Rute Neves, Marina Pinheiro, Salette Reis Research Unit on Applied Molecular Biosciences, Rede de Química e Tecnologia, Departamento de Ciências Químicas, Faculdade de Farmácia, Universidade do Porto, Porto, Portugal Abstract: Green tea is manufactured from the leaves of Camellia sinensis and has been shown to possess, among other properties, anticancer, antiobesity, antiatherosclerotic, antidiabetic, antibacterial, and antiviral effects. The beneficial effects of green tea are related to the activities of (-)-epigallocatechin gallate (EGCG). This catechin is very unstable, undergoing degradation and epimerization, which is responsible for the loss of its health benefits. Encapsulation in nanoparticles (NPs) is an effective method to protect EGCG from adverse environmental conditions. In this work, solid lipid NPs (SLN) and nanostructured lipid carriers (NLC) were successfully developed to be used as biocompatible nanocarriers, enhancing the stability of EGCG. The mean diameter of the NPs was found to be around 300–400 nm, which is suitable for oral administration. Moreover, EGCG was effectively encapsulated with a remarkable efficiency of encapsulation of 80% and 90% for SLN and NLC, respectively. In addition, high storage stability of the formulations is expected as they maintain the initial characteristics for 3 months. Limited release of EGCG from the NPs was observed in simulated gastric and intestinal fluids. MTT and lactate dehydrogenase (LDH) assays demonstrated that NPs possess low toxicity, and so have potential to be used for preventive and therapeutic EGCG supplementation. Keywords: EGCG, lipid nanoparticles, nanoparticles, nutraceuticals, supplementation

Marina Pinheiro,1,* Ricardo Ribeiro,1,* Alexandre Vieira,1,* Fernanda Andrade,2 Salette Reis1 1IUCIBIO, REQUIMTE, Chemistry Department, Faculty of Pharmacy, 2Laboratory of Pharmaceutical Technology, Department of Drug Sciences, Faculty of Pharmacy, University of Porto, Porto, Portugal *These authors contributed equally to this work Abstract: This work aimed to design, develop, and characterize a lipid nanocarrier system for the selective delivery of rifabutin (RFB) to alveolar macrophages. Lipid nanoparticles, specifically nanostructured lipid carriers (NLC), were synthetized by the high-shear homogenization and ultrasonication techniques. These nanoparticles were designed to exhibit both passive and active targeting strategies to be efficiently internalized by the alveolar macrophages, traffic to the acidified phagosomes and phagolysosomes, and release bactericidal concentrations of the antituberculosis drug intracellularly. NLC that could entrap RFB were prepared, characterized, and further functionalized with mannose. Particles’ diameter, zeta potential, morphology, drug% entrapping efficiency, and drug release kinetics were evaluated. The mannose coating process was confirmed by Fourier transform infrared. Further, the cytotoxicity of the formulations was evaluated by 3-(4,5-dimethylthiazol-2-yl)-2,5 diphenyltetrazolium bromide (MTT) assay in A549, Calu-3, and Raw 264.7 cells. The diameter of NLC formulations was found to be in the range of 175–213 nm, and drug entrapping efficiency was found to be above 80%. In addition, high storage stability for the formulations was expected since they maintained the initial characteristics for 6 months. Moreover, the drug release was pH-sensitive, with a faster drug release at acidic pH than at neutral pH. These results pose a strong argument that the developed nanocarrier can be explored as a promising carrier for safer and more efficient management of tuberculosis by exploiting the pulmonary route of administration. Keywords: lipid nanoparticles, mannose, nanostructured lipid carriers, rifabutin, tuberculosis, drug delivery systems

Alexandre CC Vieira,1,* Luíse L Chaves,1,* Marina Pinheiro,1 Domingos Ferreira,2 Bruno Sarmento,3–5 Salette Reis1 1UCIBIO, REQUIMTE, Chemistry Department, Faculty of Pharmacy, 2Laboratory of Pharmaceutical Technology, Department of Drug Sciences, Faculty of Pharmacy, 3I3S, Institute for Research and Innovation in Health, 4INEB – Institute of Biomedical Engineering, University of Porto, Porto, 5CESPU, Institute of Research and Advanced Formation in Health Sciences and Technology, University Institute of Health Sciences, Gandra, Portugal *These authors contributed equally to this work Abstract: The aim of the present work was to develop and optimize surface-functionalized solid lipid nanoparticles (SLNs) for improvement of the therapeutic index of dapsone (DAP), with the application of a design of experiments. The formulation was designed to target intestinal microfold (M-cells) as a strategy to increase internalization of the drug by the infected macrophages. DAP-loaded SLNs and mannosylated SLNs (M-SLNs) were successfully developed by hot ultrasonication method employing a three-level, three-factor Box–Behnken design, after the preformulation study was carried out with different lipids. All the formulations were systematically characterized regarding their diameter, polydispersity index (PDI), zeta potential (ZP), entrapment efficiency, and loading capacity. They were also subjected to morphological studies using transmission electron microscopy, in vitro release study, infrared analysis (Fourier transform infrared spectroscopy), calorimetry studies (differential scanning calorimetry), and stability studies. The diameter of SLNs, SLN-DAP, M-SLNs, and M-SLN-DAP was approximately 300 nm and the obtained PDI was

Catarina Costa Moura,1,2 Marcela A Segundo,1 José das Neves,3,4 Salette Reis,1 Bruno Sarmento3,4 1REQUIMTE, Department of Chemical Sciences, Faculty of Pharmacy, University of Porto, Porto, Portugal; 2Faculty of Engineering, University of Porto, Porto, Portugal; 3CESPU, Instituto de Investigação e Formação Avançada em Ciências e Tecnologias da Saúde, Instituto de Ciências da Saúde-Norte, Gandra PRD, Portugal; 4INEB – Instituto de Engenharia Biomédica, University of Porto, Porto, Portugal Background: Rheumatoid arthritis (RA) is an autoimmune disease with severe consequences for the quality of life of sufferers. Regrettably, the inflammatory process involved remains unclear, and finding successful therapies as well as new means for its early diagnosis have proved to be daunting tasks. As macrophages are strongly associated with RA inflammation, effective diagnosis and therapy may encompass the ability to target these cells. In this work, a new approach for targeted therapy and imaging of RA was developed based on the use of multifunctional polymeric nanoparticles. Methods: Poly(lactic-co-glycolic acid) nanoparticles were prepared using a single emulsion-evaporation method and comprised the co-association of superparamagnetic iron oxide nanoparticles (SPIONs) and methotrexate. The nanoparticles were further functionalized with an antibody against the macrophage-specific receptor, CD64, which is overexpressed at sites of RA. The devised nanoparticles were characterized for mean particle size, polydispersity index, zeta potential, and morphology, as well as the association of SPIONs, methotrexate, and the anti-CD64 antibody. Lastly, the cytotoxicity of the developed nanoparticles was assessed in RAW 264.7 cells using standard MTT and LDH assays.Results: The nanoparticles had a mean diameter in the range of 130–200 nm and zeta potential values ranging from -32 mV to -16 mV. Association with either methotrexate or SPIONs did not significantly affect the properties of the nanoparticles. Conjugation with the anti-CD64 antibody, in turn, caused a slight increase in size and surface charge. Transmission electron microscopy confirmed the association of SPIONs within the poly(lactic-co-glycolic acid) matrix. Both anti-CD64 and methotrexate association were confirmed by Fourier transform infrared spectroscopy, and quantified yielding values as high as 36% and 79%, respectively. In vitro toxicity studies confirmed the methotrexate-loaded nanosystem to be more effective than the free drug.Conclusion: Multifunctional anti-CD64-conjugated poly(lactic-co-glycolic acid) nanoparticles for the combined delivery of methotrexate and SPIONs were successfully prepared and characterized. This nanosystem has the potential to provide a new theranostic approach for the management of RA. Keywords: FcγRI, methotrexate, poly(lactic-co-glycolic acid), superparamagnetic iron oxide nanoparticles, targeted drug delivery

Maria João Gomes,1 Susana Martins,2,3 Domingos Ferreira,2 Marcela A Segundo,1 Salette Reis1 1REQUIMTE, Laboratory of Applied Chemistry, Department of Chemical Sciences, Faculty of Pharmacy, 2Laboratory of Pharmaceutical Technology, Department of Drug Sciences, Faculty of Pharmacy, University of Porto, Porto, Portugal; 3Department of Physics, Chemistry and Pharmacy, University of Southern Denmark, Odense, Denmark Abstract: Alopecia is a dermatological disorder, commonly known as hair loss, which affects up to half of the Caucasian male population by middle age, and almost all (95%) Caucasian men by old age. Considering that alopecia affects so many people and that there is currently no scientifically proven treatment with few side effects, new drug-delivery systems able to improve alopecia therapy are urgently required. With this purpose in mind, the present study aimed to develop lipid nanoparticles (nanostructured lipid carriers) with the ability to incorporate and deliver anti-alopecia active compounds (minoxidil and finasteride) into the dermis and hair follicles. Lipid nanoparticles, prepared by ultrasonication method, showed mean particle sizes around 200 nm, which is sufficient for reaching the dermis and hair follicles, and zeta potential values around -30 mV, which indicates good physical stability. Over 28 days of storage, no significant variations in these parameters were observed, which indicates that all nanoformulations are stable in storage over that period. Cryo-scanning electron microscope measurements showed that all the lipid nanoparticles exhibited a spherical shape and a smooth surface regardless of their composition. Differential scanning calorimetry studies allowed the determination of phase transition temperatures and confirmed the recrystallization of the lipid nanoparticles (recrystallization index between 11% and 86%). A high loading efficiency was achieved for finasteride (between 70% and 90%), while less than 30% was achieved for minoxidil nanoparticles, over 28 days. Controlled release assays in physiological conditions demonstrated that nanoparticles loaded with minoxidil yielded a prolonged release, as desired. Penetration assays through pig ear skin demonstrated that nanoparticles loaded with minoxidil and finasteride had low levels of penetration. These results suggest that the proposed novel formulation presents several good characteristics indicating their suitability for dermal delivery of anti-alopecia active compounds. Keywords: nanostructured lipid carriers (NLC), alopecia, anti-alopecia therapy, minoxidil, finasteride

Ana Rute Neves,1 Marlene Lúcio,1 Susana Martins,2,3 José Luís Costa Lima,1 Salette Reis11REQUIMTE, Chemistry Department, Faculty of Pharmacy, University of Porto, 2Laboratory for Pharmaceutical Technology/Research Centre in Pharmaceutical Sciences, Faculty of Pharmacy, University of Porto, 3Institute of Biomedical Engineering, University of Porto, PortugalIntroduction: Resveratrol is a polyphenol found in grapes and red wines. Interest in this polyphenol has increased due to its pharmacological cardio- and neuroprotective, chemopreventive, and antiaging effects, among others. Nevertheless, its pharmacokinetic properties are less favorable, since the compound has poor bioavailability, low water solubility, and is chemically unstable. To overcome these problems, we developed two novel resveratrol nanodelivery systems based on lipid nanoparticles to enhance resveratrol's oral bioavailability for further use in medicines, supplements, and nutraceuticals.Methods and materials: Solid lipid nanoparticles (SLNs) and nanostructured lipid carriers (NLCs) loaded with resveratrol were successfully produced by a modified hot homogenization technique. These were completely characterized to evaluate the quality of the developed resveratrol-loaded nanoparticles.Results: Cryo-scanning electron microscopy morphology studies showed spherical and uniform nanoparticles with a smooth surface. An average resveratrol entrapment efficiency of ~70% was obtained for both SLNs and NLCs. Dynamic light scattering measurements gave a Z-average of 150–250 nm, polydispersity index of ~0.2, and a highly negative zeta potential of around −30 mV with no statistically significant differences in the presence of resveratrol. These characteristics remained unchanged for at least 2 months, suggesting good stability. Differential scanning calorimetry studies confirmed the solid state of the SLNs and NLCs at both room and body temperatures. The NLCs had a less ordered crystalline structure conferred by the inclusion of the liquid lipid, since they had lower values for phase transition temperature, melting enthalpy, and the recrystallization index. The presence of resveratrol induced a disorder in the crystal structure of the nanoparticles, suggesting a favoring of its entrapment. The in vitro release studies on conditions of storage showed a negligible resveratrol release over several hours for both nanosystems and the in vitro simulation of gastrointestinal transit showed that the resveratrol remained mostly associated with the lipid nanoparticles after their incubation in digestive fluids.Conclusion: Both nanodelivery systems can be considered suitable carriers for oral administration, conferring protection to the incorporated resveratrol and allowing a controlled release after uptake.Keywords: nanodelivery systems, solid lipid nanoparticles, nanostructured lipid carriers, polyphenol

The NitroEurope Integrated Project (2006-2011) aimed to gain a better understanding of the nitrogen cycle and its impacts on the European greenhouse gas balance. Over sixty project partners collected large volumes of data from sites all over Europe. There are currently more than 15 forest sites in 11 countries, including beech, oak, spruce and mixed forests. The collected data are at different temporal resolutions, from one-off measurements to 30-minute time-series data. Around 500 variables (plus attributes) are measured, including soil and plant data, details of cultivation management for natural and manipulated sites, long-term datasets of flux and concentrations of greenhouse gas and pollutants and their precursors, and micrometeorology data. The NitroEurope research community therefore needed a database to provide easy upload and extraction of data for analysis, interpretation and modelling. A bespoke database with a web-based graphical user interface (GUI) in a user-friendly and attractive online environment was produced by the NitroEurope (NitroEurope 2011) database development team. The software provides a flexible interface between Microsoft Excel workbooks and an Oracle database. The database “Form Manager” enables construction of database forms which reflect the project’s Excel data workbook templates. The software locates data according to Excel worksheet and cell references. The database “Uploader” extracts the specified data from completed Excel templates and uploads data directly to the Oracle relational database tables through the web front-end. Data are run through a series of automatic checks on upload which can be verified using an online graphing tool. Data are then validated and made available to the NitroEurope community for downloading. The database “Reporting” tools enable data from different sites and activities to be brought together and datasets can be previewed and graphed before they are downloaded. The database has almost 300 users and currently contains over eight million rows of data. The data will be made available to the wider scientific community two years after the project ends (Spring 2013). The database structure is extremely flexible and has been used for the storage and reporting of other time-series project data at our institute.

We report studies on the unusual frequency dispersion of the dielectric permittivity maxima of methylammonium lead iodide pellets at temperatures around the tetragonal–cubic phase transition. The origin of this observed permittivity response was studied in terms of grains and grain boundaries' contributions in impedance, electric modulus, dielectric permittivity, and electrical conductivity. From theoretical fits of impedance and electric modulus measurements at different temperatures over a frequency range of 103–10 Hz, the reconstructed contributions of the grain boundary and grain permittivities show peaks around 339 K and 384 K, respectively. The origin of the grain boundary permittivity peak is discussed in terms of heterogenic ionic conduction associated with I− and MA+ ions in MAPbI3, while the peak in grain permittivity at high temperature is in terms of ionization of intrinsic carriers. The high value of the grain dielectric permittivity (ε g = 1193) , compared to the reconstructed grain boundary permittivity (ε g b = 53) , suggests a possible relaxor ferroelectric behavior with a diffuse phase transition for methylammonium lead iodide. The difficulties in confirming the ferroelectric nature of this halide perovskite based on impedance and electrical module data are also discussed. [ABSTRACT FROM AUTHOR]