Cellulose nano crystals (CNCs) are promising materials for energy efficient buildings related to the control of reflectivity and heat absorption/reflection of light. In this sense it is important to improve CNCs films fire retardant properties, which can be achieved by adding clays. Cellulose nanocrystals (CNCs) and nanolayers obtained from Sodium Fluorohectorite (NaFh) synthetic clay are both known to form liquid crystalline phases in aqueous suspensions. CNCs form cholesteric phases, which structure is preserved after water evaporation, while dry NaFh nanolayers aligned films collapse. In this initial work, it is shown that CNCs are compatible with NaFh clay. We demonstrate that the liquid crystalline phase of CNCs in water is not destroyed by the presence of NaFh nanolayers. The NaFh nanolayers act as planar anchoring surfaces to the cellulose nanorods and, after evaporation of the water coloured films are obtained. The precursor solutions and the photonic films were investigated by Describe several techniques.

Surface modification of zinc oxide nanoparticles (ZnO NPs) is a strategy to tune their biocompatibility. Herein we report on the synthesis of a series of fluorescent ZnO NPs modified with 2-10% (3-glycidyloxypropyl)trimethoxysilane (GPTMS) to investigate the fluorescence properties and to explore their applications in microbiology and biomedicine. The obtained ZnO NPs were characterized by X-ray diffraction (XRD), high resolution transmission electron microscopy (HRTEM) and Fourier transform infrared spectroscopy (FTIR). Size reduction occurred from ca. 13 nm in unmodified ZnO to 3-4 nm in silane-modified samples and fluorescence spectra showed size-dependent variation of the photoemission bands' intensity. The antibacterial and cytotoxic activities were investigated on Gram-negative (Escherichia coli) and Gram-positive (Staphylococcus aureus) bacteria, and in ovarian (A2780) and prostate (PC3) cancer cells by tetrazolium/formazan-based methods. The antibacterial effect was higher for E. coli than S. aureus, while the cytotoxic activity was similar for both cancer cells and varied with the particle size. Cell death by apoptosis, and/or necrosis versus autophagy, were explored by flow cytometry using an Annexin V based-method and transmission electron microscopy (TEM). The main mechanism of ZnO NPs toxicity may involve the generation of reactive oxygen species (ROS) and the induction of apoptosis or autophagy. This work revealed the potential utility of GPTMS-modified ZnO NPs in the treatment of bacterial infection and cancer.

Flexible and stretchable energy-storage batteries and supercapacitors suitable for wearable electronics are at the forefront of the emerging field of intelligent textiles. In this context, the work here presented reports on the development of a symmetrical wire-based supercapacitor able to use the wearer’s sweat as the electrolyte. The inner and outer electrodes consists of a carbon-based thread functionalized with a conductive polymer (polypyrrole) which improves the electrochemical performances of the supercapacitor. The inner electrode is coated with electrospun cellulose acetate fibres, as the separator, and the outer electrode is twisted around it. The electrochemical performances of carbon-based supercapacitors were analyzed using a simulated sweat solution and displayed a specific capacitance of 2.3 F.g−1, an energy of 386.5 mWh.kg−1 and a power density of 46.4 kW.kg−1. Moreover, cycle stability and bendability studies were performed. Such energy conversion device has exhibited a stable electrochemical performance under mechanical deformation, over than 1000 cycles, which make it attractive for wearable electronics. Finally, four devices were tested by combining two supercapacitors in series with two in parallel demonstrating the ability to power a LED.

We demonstrate a simple and accessible method for enhancing textiles with custom piezo-resistive properties. Based on in-situ polymerization, our method offers seamless integration at the material level, preserving a textile's haptic and mechanical properties. We demonstrate how to enhance a wide set of fabrics and yarns using only readily available tools. During each demo session, conference attendees may bring textile samples which will be polymerized in a shared batch. Attendees may keep these samples. While the polymerization is happening, attendees can inspect pre-made samples and explore how these might be integrated in functional circuits. Examples objects created using polymerization include rapid manufacturing of on-body interfaces, tie-dyed motion-capture clothing, and zippers that act as potentiometers.

Background The awareness of environmental and socio-economic impacts caused by greenhouse gas emissions from the livestock sector leverages the adoption of strategies to counteract it. Feed supplements can play an important role in the reduction of the main greenhouse gas produced by ruminants—methane (CH\textsubscript{4}). In this context, this study aims to assess the effect of two biochar sources and inclusion levels on rumen fermentation parameters \textit{in vitro}. Methods Two sources of biochar (agro-forestry residues, AFB, and potato peel, PPB) were added at two levels (5 and 10%, dry matter (DM) basis) to two basal substrates (haylage and corn silage) and incubated 24-h with rumen inocula to assess the effects on CH\textsubscript{4} production and main rumen fermentation parameters \textit{in vitro}. Results AFB and PPB were obtained at different carbonization conditions resulting in different apparent surface areas, ash content, pH at the point of zero charge (pHpzc), and elemental analysis. Relative to control (0% biochar), biochar supplementation kept unaffected total gas production and yield (mL and mL/g DM, \textit{p} = 0.140 and \textit{p} = 0.240, respectively) and fermentation pH (\textit{p} = 0.666), increased CH\textsubscript{4}production and yield (mL and mL/g DM, respectively, \textit{p} = 0.001) and ammonia-N (NH\textsubscript{3}-N, \textit{p} = 0.040), and decreased total volatile fatty acids (VFA) production (\textit{p} < 0.001) and H\textsubscript{2} generated and consumed (\textit{p} ≤ 0.001). Biochar sources and inclusion levels had no negative effect on most of the fermentation parameters and efficiency. Acetic:propionic acid ratio (\textit{p} = 0.048) and H\textsubscript{2} consumed (\textit{p} = 0.019) were lower with AFB inclusion when compared to PPB. Biochar inclusion at 10% reduced H\textsubscript{2} consumed (\textit{p} < 0.001) and tended to reduce total gas production (\textit{p} = 0.055). Total VFA production (\textit{p} = 0.019), acetic acid proportion (\textit{p} = 0.011) and H\textsubscript{2} generated (\textit{p} = 0.048) were the lowest with AFB supplemented at 10%, no differences being observed among the other treatments. The basal substrate affected most fermentation parameters independently of biochar source and level used. Discussion Biochar supplementation increased NH\textsubscript{3}-N content, \textit{iso}-butyric, \textit{iso}-valeric and valeric acid proportions, and decreased VFA production suggesting a reduced energy supply for microbial growth, higher proteolysis and deamination of substrate N, and a decrease of NH\textsubscript{3}-N incorporation into microbial protein. No interaction was found between substrate and biochar source or level on any of the parameters measured. Although AFB and PPB had different textural and compositional characteristics, their effects on the rumen fermentation parameters were similar, the only observed effects being due to AFB included at 10%. Biochar supplementation promoted CH\textsubscript{4} production regardless of the source and inclusion level, suggesting that there may be other effects beyond biomass and temperature of production of biochar, highlighting the need to consider other characteristics to better identify the mechanism by which biochar may influence CH\textsubscript{4} production.

The monoheme outer membrane cytochrome F (OmcF) from Geobacter sulfurreducens plays an important role in Fe(III) reduction and electric current production. The electrochemical characterization of this cytochrome has shown that its redox potential is modulated by the solution pH (redox-Bohr effect) endowing the protein with the necessary properties to couple electron and proton transfer in the physiological range. The analysis of the OmcF structures in the reduced and oxidized states showed that with the exception of the side chain of histidine 47 (His⁴⁷), all other residues with protonatable side chains are distant from the heme iron and, therefore, are unlikely to affect the redox potential of the protein. The protonatable site at the imidazole ring of His⁴⁷ is in the close proximity to the heme and, therefore, this residue was suggested as the redox-Bohr center. In the present work, we tested this hypothesis by replacing the His⁴⁷ with non-protonatable residues (isoleucine – OmcFH47I and phenylalanine – OmcFH47F). The structure of the mutant OmcFH47I was determined by X-ray crystallography to 1.13 Å resolution and showed only minimal changes at the site of the mutation. Both mutants were ¹⁵N-labeled and their overall folding was confirmed to be the same as the wild-type by NMR spectroscopy. The pH dependence of the redox potential of the mutants was measured by cyclic voltammetry. Compared to the wild-type protein, the magnitude of the redox-Bohr effect in the mutants was smaller, but not fully abolished, confirming the role of His⁴⁷ on the pH modulation of OmcF’s redox potential. However, the pH effect on the heme substituents’ NMR chemical shifts suggested that the heme propionate P₁₃ also contributes to the overall redox-Bohr effect in OmcF. In physiological terms, the contribution of two independent acid–base centers to the observed redox-Bohr effect confers OmcF a higher versatility to environmental changes by coupling electron/proton transfer within a wider pH range.

Microbial electrosynthesis is an emerging green technology that explores the capability of a particular group of microorganisms to drive their metabolism toward the production of hydrogen or value-added chemicals from electrons supplied by electrode surfaces. The cytochrome PccH showed the largest increase in transcription when electrons are supplied to Geobacter sulfurreducens biofilms. Gene knock-out experiments have shown that the electron transfer toward G. sulfurreducens cells was completely inhibited by the deletion of the gene encoding for cytochrome PccH. This identifies a crucial role for this protein in G. sulfurreducens microbial electrosynthesis mechanisms, which are currently unknown. In this work, we present the backbone (1H, 13C and 15N) and heme assignment for PccH in the oxidized state. The data obtained paves the way to identify and structurally map the molecular interaction regions between the cytochrome PccH and its physiological redox partners.

Affinity‐triggered assemblies rely on affinity interactions as the driving force to assemble physically‐crosslinked networks. WW domains are small hydrophobic proteins binding to proline‐rich peptides that are typically produced in the insoluble form. Previous works attempted the biological production of the full WW domain in tandem to generate multivalent components for affinity‐triggered hydrogels. In this work, an alternative approach was followed by engineering a 13‐mer minimal version of the WW domain that retains the ability to bind to target proline‐rich peptides. Both ligand and target peptides were produced chemically and conjugated to multivalent polyethylene glycol, yielding two components. Upon mixing, they together form soft biocompatible affinity‐triggered assemblies, stable in stem cell culture media, and displaying mechanical properties in the same order of magnitude as for those hydrogels formed with the full WW protein in tandem.

The rising interest in the use of Geobacter bacteria for biotechnological applications demands a deep understanding of how these bacteria are able to thrive in a variety of environments and perform extracellular electron transfer. The Geobacter metallireducens bacterium can couple the oxidation of a wide range of compounds to the reduction of several extracellular acceptors, including heavy metals, toxic organic compounds or electrode surfaces. The periplasmic c-type cytochrome PpcA from this bacterium is a member of a family composed of five periplasmic triheme cytochromes, which are important to bridge the electron transfer between the cytoplasm and the extracellular environment. To better understand the functional mechanism of PpcA it is essential to obtain structural data for this cytochrome. In this work, the geometry of the heme axial ligands, as well as the magnetic properties of the hemes were determined for the oxidized form of the cytochrome, using the 13C NMR chemical shifts of the heme α-substituents. The results were further compared with those previously obtained for the homologous cytochrome from Geobacter sulfurreducens. The orientations of the axial histidine planes and the magnetic properties of the hemes are conserved in both proteins. Overall, the results obtained allowed the definition of the orientation of the magnetic axes of PpcA from G. metallireducens, which will be used as constraints to assist the solution structure determination of the cytochrome in the oxidized form.

One of the most promising approaches to produce industrial-compatible Transparent Conducting Materials (TCMs) with excellent characteristics is the fabrication of TCO/metal/TCO multilayers. In this article, we report on the electro-optical properties of a novel high-performing TCO/metal/TCO structure in which the intra-layer is a micro-structured metallic grid instead of a continuous thin film. The grid is obtained by evaporation of Ag through a mask of polystyrene colloidal micro-spheres deposited by the Langmuir-Blodgett method and partially dry-etched in plasma. IZO/Ag grid/IZO structures with different thicknesses and mesh dimensions have been fabricated, exhibiting excellent electrical characteristics (sheet resistance below 10 Ω/□) and particularly high optical transmittance in the near-infrared spectral region as compared to planar (unstructured) TCM multilayers. Numerical simulations were also used to highlight the role of the Ag mesh parameters on the electrical properties.

Properties such as particle orientation{,} flowability{,} packing{,} compaction{,} syringeability{,} suspension stability and dissolution are the most influenced by changes in the crystal habit and polymorphic form of a drug substance. The crystal habit of a drug substance (long-acting β2-adrenergic agonist (LABA)){,} as well as its purity and polymorphic stability{,} was studied after performing slurry tests with 1{,}2-dimethoxyethane : heptane solution at 50 °C. In these slurry tests{,} the product was kept suspended and undissolved{,} with agitation{,} for polymorphic conversion evaluation. Since no significant modifications were observed in the crystal shape and dimensions at 50 °C{,} a new slurry test was performed at a temperature above the melting point of the starting material (80 °C). In the latter test{,} it was possible to obtain crystals with increased dimensions by 480% compared with the starting material. Additionally{,} the desired polymorphic form (form I) was obtained as well as an acceptable purity of approximately 99%. These are promising results{,} not only for downstream purposes{,} but also concerning the bioavailability of the drug substance. This work shows that working at a temperature higher than the melting point of the compound seems to modify the crystal habit of the product.

Nuclear Magnetic Resonance (NMR) spectroscopy is extremely powerful to study distinct biological systems ranging from biomolecules to specific metabolites. This chapter presents the basic concepts of the technique and illustrates its potential to study such systems. Similarly, to other spectroscopic techniques, the theoretical background of NMR is sustained by detailed mathematics and physical chemistry concepts, which were kept to the minimum. The intent is to introduce the fundamentals of the technique to science students from different backgrounds. The basic concepts of NMR spectroscopy are briefly presented in the first section, and the following sections describe applications in the biosciences field, using electron transfer proteins as model, particularly cytochromes. The heme groups endow cytochromes with particular features making them excellent examples to illustrate the high versatility of NMR spectroscopy. The main methodologies underlying protein solution structure determination are discussed in the second section. This is followed by a description of the main experiments explored to structurally map protein-protein or protein-ligand interface regions in molecular complexes. Finally, it is shown how NMR spectroscopy can assist in the functional characterization of multiheme cytochromes.

Reactor hydrodynamics can play a significant role in antisolvent crystallizations. In this work, the impact of suspension height/clearance ratio (H/C) and power per volume (PV) on the particle size distribution (PSD) parameters Dv10, Dv50, and Dv90 of an active pharmaceutical ingredient (API) were evaluated. The API solution was added near the liquid surface of the antisolvent with a buret, at a rate of approximately 5 mL/min, between the impeller and the reactor’s wall. Statistical models were developed, and it was found that PSD parameters seem to be influenced by the H/C and PV. A relationship between the PSD parameters and the nucleation rate was also witnessed. Furthermore, different mathematical methodologies (indicator function and Monte Carlo simulations) were used to obtain a design space comprising the probability of success of having PSD parameters within specification. An operating region comprising the probability of success was estimated, which can aid in minimizing the risk of failure in antisolvent crystallization processes and consequently help reduce the financial losses caused by out-of-specification batches.

The scale-up of crystallization processes is a challenging step in production of active pharmaceutical ingredients (APIs). When moving from lab to industrial scale, the mixing conditions tend to modify due to the different geometry and agitation performance, which is particularly important in anti-solvent crystallizations where the size of the crystals depends on the mixing and incorporation of the anti-solvent in the solution. In this work, the results obtained in anti-solvent lab-scale crystallization experiments were used to develop multivariate statistical models predicting Particle Size Distribution (PSD) parameters (Dv10, Dv50 and Dv90) in function of predictors such as percentage of volume, power per volume and tip speed. Firstly, the collinearity among the predictors was assessed by Variance Inflation Factor (VIF) diagnosis. Subsequently, least squares method was employed to find correlations among the predictors and output variables. The optimization of the models was executed by testing quadratic, logarithmic and square root terms of the predictors and removing the least statistically significant regression coefficient. The quality of the fitting was evaluated in terms of adjusted R2 (R2adj). The modelled Dv10, Dv50 and Dv90 values presented a good fitting to the experimental data, with R2adj higher than 0.79, either when using power per volume or tip speed along the percentage of volume as predictors. Afterwards, the particle size distribution parameters of industrial scale production were predicted using the previously developed models. The deviations between predicted and experimental values were lower than 17%. This demonstrates that multivariate statistical models developed in lab-scale conditions can be successfully used to predict particle size distribution in industrial-size vessels.

POxylated polyurea dendrimer (PUREG4OOx48)-based nanoparticles were loaded with paclitaxel (PTX) and doxorubicin (DOX) and micronized with chitosan (CHT) by using supercritical CO2-assisted spray drying (SASD). Respirable, biocompatible, and biodegradable dry powder formulations (DPFs) were produced to effectively transport and deliver the chemotherapeutics with a controlled rate to the deep lung. In vitro studies performed with the use of the lung adenocarcinoma cell line showed that DOX@PUREG4OOx48 nanoparticles were much more cytotoxic than the free drug. Additionally, the DPFs did not show higher cytotoxicity than the respective nanoparticles, and DOX-DPFs showed a higher chemotherapeutic effect than PTX formulations in adenocarcinoma cells.

Many diseases have their treatment options narrowed and end up being fatal if detected during later stages. As a consequence, point-of-care devices have an increasing importance for routine screening applications in the health sector due to their portability, fast analyses and decreased cost. For that purpose, a multifunctional chip was developed and tested using gold nanoprobes to perform RNA optical detection inside a microfluidic chip without the need of molecular amplification steps. As a proof-of-concept, this device was used for the rapid detection of chronic myeloid leukemia, a hemato-oncological disease that would benefit from early stage diagnostics and screening tests. The chip passively mixed target RNA from samples, gold nanoprobes and saline solution to infer a result from their final colorimetric properties. An optical fiber network was used to evaluate its transmitted spectra inside the chip. Trials provided accurate output results within 3 min, yielding signal-to-noise ratios up to 9 dB. When compared to actual state-of-art screening techniques of chronic myeloid leukemia, these results were, at microscale, at least 10 times faster than the reported detection methods for chronic myeloid leukemia. Concerning point-of-care applications, this work paves the way for other new and more complex versions of optical based genosensors.