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Palygorskite has attracted particular attention as a specialized adsorbent due to its high specific surface area, porous texture and abundant surface groups, but its processing for commercial products makes the resulting material more expensive. In this scope, the aim of this work is to evaluate the potential of Brazilian naturally occurring palygorskite samples with low processing degree as an alternative to commercial palygorskites adsorbents for methylene blue, evaluating samples with different compositions, morphologies and microporous profiles. Materials were characterized using FTIR, X-ray diffraction, X-ray fluorescence, scanning electron microscopy, and surface area analysis (BET method). The Brazilian ones were processed in bar and disk mills and passed through a # 325 mesh sieve system. All samples showed common palygorskite X-ray diffraction patterns and specific surface area ranging from 100 to 147 m/g. The application of clay samples was investigated for the adsorption of methylene blue (MB) dye, and the influence time of adsorption, initial dye concentration and adsorbent dosage were evaluated. The methylene blue adsorption was best described by the pseudo-second order model. The adsorption kinetics of methylene blue by palygorskite conforms to the pseudo-second-order model (R = 0,9997). The maximum removal capacity for methylene blue was determined to be 694 (±36.53) mg/g. Additionally, the Freundlich model demonstrated the most favorable mathematical fit. Adsorption capacities varied between 49 and 150 mg/g for 300 mg/L MB solutions, with noteworthy performance exhibited by Brazilian samples, achieving up to twice the adsorption compared to their commercial counterparts, despite possessing lower specific surface areas. The presence of two distinct pore modes, centered at 25 and 45 Å, proved pivotal in the sample with the highest adsorption capacity, reaching adsorption equilibrium at 40 min.

Despite the health benefits of the sun, overexposure to solar radiation without proper precautions can cause irreversible damage to exposed skin. In the search for balance between the risks and benefits of exposure to solar radiation in human health, a technological alternative was found, the incorporation of photoprotective products in lipid nanoparticulate systems for topical application. These nanometric systems have demonstrated several advantages when used as adjuvants in photoprotection compared to chemical and/or physical sunscreens alone. The increase in the sun protection factor (SPF), photostability and UV action spectrum are parameters that have benefited from the application of these systems in order to increase the effectiveness and safety of photoprotective formulations containing organic and/or inorganic sunscreens

Development of new medicinal products for particular therapeutic treatment or for better manipulations with better quality and less side effects are possible as a result of advanced inorganic and organic materials application, among which zeolites, due to their properties and versatility, have been gaining attention. This paper is an overview of the development in the use of zeolite materials and their composites and modifications as medicinal products for several purposes such as active agents, carriers, for topical treatments, oral formulations, anticancer, the composition of theragnostic systems, vaccines, parenteral dosage forms, tissue engineering, etc. The objective of this review is to explore the main properties of zeolites and associate them with their drug interaction, mainly addressing the advances and studies related to the use of zeolites for different types of treatments due to their zeolite characteristics such as molecule storage capacity, physical and chemical stability, cation exchange capacity, and possibility of functionalization. The use of computational tools to predict the drug—zeolite interaction is also explored. As conclusion was possible to realize the possibilities and versatility of zeolite applications as being able to act in several aspects of medicinal products.

Vascular stents (VS) have revolutionized the treatment of cardiovascular diseases, as evidenced by the fact that the implantation of VS in coronary artery disease (CAD) patients has become a routine, easily approachable surgical intervention for the treatment of stenosed blood vessels. Despite the evolution of VS throughout the years, more efficient approaches are still required to address the medical and scientific challenges, especially when it comes to peripheral artery disease (PAD). In this regard, three-dimensional (3D) printing is envisaged as a promising alternative to upgrade VS by optimizing the shape, dimensions and stent backbone (crucial for optimal mechanical properties), making them customizable for each patient and each stenosed lesion. Moreover, the combination of 3D printing with other methods could also upgrade the final device. This review focuses on the most recent studies using 3D printing techniques to produce VS, both by itself and in combination with other techniques. The final aim is to provide an overview of the possibilities and limitations of 3D printing in the manufacturing of VS. Furthermore, the current situation of CAD and PAD pathologies is also addressed, thus highlighting the main weaknesses of the already existing VS and identifying research gaps, possible market niches and future directions.

Layered double hydroxides (LDH) consist of brucite-like layers containing di- and trivalent metal ions with interchangeable counter anions and solvation molecules that are present between the layers [1]. LDH find several applications in the pharmaceutical field due to their chemical stability, biocompatibility and high mechanical strength, and they are well known to support cellular processes, such as cell differentiation and viability [2]. LDH have very high potentialities for industrial applications, but their synthesis often requires a high number of steps, which could also lead to the production of great amounts of waste [3]. Given these premises, the goal of the work is the design of sustainable strategies for the synthesis of LDH in view of a continuous manufacturing process. LDH were produced through two well-known methods using new green synthesis conditions and their properties were compared to investigate the differences given by the LDH compositions. In particular, their biological properties were considered for a future application in the biomedical field, especially in tissue engineering. Nitrate salts of Mg2+, Zn2+, Cu2+, Al3+, and Fe3+, chosen as bio-enabling cations, were used. First, a co-precipitation method through a fast addition of salts and reduced aging time was developed, using ammonia as an alkaline agent. Few studies are reported using this chemical for the synthesis of LDH. Being a volatile molecule, the excess of ammonia could be easily removed and trapped, together with some of the byproducts that might be formed during the process. Second, the urea hydrolysis through microwave and hydrothermal treatment was considered. The synthesis parameters were adjusted to minimize the waste production. In all cases, the LDH were characterized both as prepared and upon centrifugation/washing, in view of a single step synthesis without water and components waste. The XRD patterns showed that LDH phases represent the major part in the unwashed samples

The intensive use of antibiotics and especially sulfonamides in the livestock industry is getting an alarming level. The presence of these drugs in wastewaters, rivers and underground waters is increasing considerably in developing countries. At the same time, montmorillonite is a natural, low-cost, non-toxic, biocompatible clay with a high adsorption capacity. It is potentially useful as a nanocarrier to design sulfonamides dosage forms. In this work, the interaction between the drug and the clay mineral has been studied from an experimental and computational atomistic point of view to improve the drug¿s biopharmaceutical profile. The results showed the potential enhancement of the drug solubility due to the correct adsorption of sulfonamides in the clay interlayer space. The molecular interactions of these drugs with the surfaces of clay minerals can be interesting for evaluating their mobility in soils and for preparing composite complexes for optimal use. In this work, the intercalation of sulfonamides, such as sulfathiazole, sulfamethazine, sulfamethoxazole, sulfachloropyridazine and sulfacetamide, into the interlayer space of montmorillonite (MNT) is studied at molecular level by using computational modeling, molecular dynamics and DFT calculations. Most of these intercalations are energetically favourable, where the role of water molecules is critical. In general, the bioavailability of these compounds by intercalation in MNT is bigger than from the crystalline powder. The spectroscopic properties of these systems showed interesting frequency shifts in the bands of the IR spectrum produced during the intercalation in the confined space of MNT. These results predict that the IR spectroscopy as an interesting analytical technique for monitoring the intercalation of drugs in clay minerals.

Mechanochemistry, an enabling technology, recently produced a new Urea/Citric Acid polymer. The method of synthesis is a catalyst and solvent-free clean route. The synthesized polymers presented superior thermal stability and crystallinity compared to the solution process. Furthermore, this method made it possible to produce a selective condensation reaction of urea in the solid state. In this work, improvements in the production process were carried out by adding a hygroscopic material. In addition, modifications were made to the polymer structure by adding different clays (Veegun HS and Sepiolite PS9), aiming to change the material¿s physicochemical properties to improve the processability of the obtained polymer. After synthesis, the obtained polymeric material was filtered off and dried. The polymer was characterized by Infrared spectroscopy (FTIR), Matrix-Assisted Laser Desorption Ionization Process ¿ (MALDITOF), XRPDSolid- state Characterization, Thermogravimetry analysis ¿ TGA, Differential scanning calorimetry¿ DSC and Scanning Electron Microscopy. Preliminary results suggest modification of the reaction, altering the molecular mass of the polymer with the addition of magnesium sulfate and structural changes with the addition of clays. This polymer has biodegradable characteristics and possible applications in the cosmetics industry.

Food loss and waste (FLW) is one of the most serious social, economic, and environmental issues undermining our planet sustainability [1]. According to Food and Agriculture Organization (FAO), nearly 1.3 billion tons of food are lost along the food supply chain.The increasing demand for new food packaging materials, which satisfy people requirements, provided thrust for advancement of nanomaterials science. Inherent permeability of polymeric materials to gases and vapours, and their poor barrier and mechanical properties have boosted interest in developing new strategies to improve these properties [2].Nowadays, the application of clay materials in food packaging is getting attention due to their mechanical, chemical, barrier (against oxygen, carbon dioxide, ultraviolet, moisture, and volatiles) and thermal properties [3].Given these premises, the aim of this work was the design and the development of innovative and sustainable packaging materials to limit the food waste, prolong the shelf-life of food and reduce environmental pollution. At this purpose, PVA-based fibers loaded with different concentrations of montmorillonite (MMT), a natural clay, were manufactured by means of electrospinning. . Clay minerals were grounded in a mortar, sieved with a 75 ¿m sieve and the blends were prepared by the addition of MMT to the polymeric blend. The systems were obtained using an electrospinning apparatus (STKIT-40, Linari Engineering, Italy), equipped with a high-voltage power supply (40 kV), a volumetric pump (Razel R99-E), a 10 mL syringe, and a conductive static collector, covered by aluminum foil.The systems were characterized using a multidisciplinary approach including morphology, size, solid state, thermal profiles, mechanical properties, ethylene scavenging activity and antioxidant properties. All the systems were characterized by fibers and a smooth morphology and preserved their structures upon hydration independently of their composition. The systems showed also

Three-dimensional printing (3DP) is an additive manufacturing technique that creates a physical three-dimensional piece from a digital computer design. One of the most important advantages of 3DP lies in its versatility, demonstrated by the wide variety of 3DP techniques currently available and the plethora of materials that can be used, to the possibility of adapting the dimensions and shape of the 3D construct just by changing the digital design to be printed. 3DP has influenced a significant number of areas. Regarding the pharmaceutical field, 3DP has opened a new door to the development of tailor-made dosage forms and medical devices (Desu et al., 2021). 3DP has even adapted to the idiosyncrasies of tissue engineering and regenerative medicine, enabling the production of anatomical models (acellular scaffolds) (Wang and Yang, 2021) and tailor-made 3D tissues and organs (cellular scaffolds) (Agarwal et al., 2020). In the last case, ink formulations are based on biocompatible and biodegradable polymers with high water content like gelatin, alginate, chitosan, fibrinogen, collagen, etc. However, their low mechanical resistance compromises their functionality and handling. At this point, there is a need for biocompatible ingredients to improve the limitations of the aforementioned polymeric ingredients. Among the potential candidates, inorganic materials like clay minerals (natural and synthetic) have proven their usefulness as mechanical reinforcement and rheology additives of different polymers (Ruiz-Hitzky et al., 2013). Moreover, they are naturally occurring materials with recognized biocompatibility and bioactivity, revealing them as optimal candidates for this cutting-edge technology. The pairing of ¿clay minerals¿ and ¿3DP¿ is a rather recent field of study. For the particular case of 3D bioprinting and tissue engineering, the number of publications dealing with clay minerals is still scarce but those already published highlight that these ingredients are use

PBS hybrid biocomposites based on clay and natural fibers (wood sawdust from Brazilian trees and canabrava fiber) were developed for application in the manufacture of tubes used in planting seedlings for agriculture to reduce the generation of plastic waste. The PBS hybrid biocomposites were produced using two natural fibers and/or montmorillonite clay wood sawdust and canabrava. Additionally, the influence of lignin incorporation was evaluated. The PBS is bio-based with an MFR of 22 g/10min (at 190ºC and 2.16kg). Wood sawdust (mean diameter of 0.686 mm) is a residue from lumber companies that work with Brazilian trees, such as Massaranduba, Copaiba, and Argelin. The Canabrava plant (Gynerium sagittatum) is frequently used by local communities to manufacture baskets and handicrafts in Brazil. The PBS-clay biocomposites were prepared with up to 10 wt% of clay in their composition. The canabrava fiber was ground to be mixed with PBS containing between 10-40% of the threads. The materials were dried at 70ºC for 3 hours. The bio-composites were obtained by melt blending using a twin screw extruder (D=16 mm and L/D=40) in compositions from 10 to 40% of fibers with or without lignin to evaluate its effect on melt flow rate. Good melt flow results and mechanical properties were obtained when PBS was mixed with up to 30% wood sawdust and 10% lignin and the mix of canabrava fiber and clay. As expected, adding wood sawdust fiber and canabrava reduces the viscosity of the melt. Still, adding lignin has a lubricating effect during processing, increasing the melt flow, which is interesting for the injection process. Furthermore, thermal stability was improved by adding clay to the PBS matrix. The composites were characterized by mechanical tests, scanning electron microscopy, thermogravimetric analysis, and differential scanning calorimetry. Finally, a combination of PBS and montmorillonite clay, as well as PBS and natural fibers produced hybrid composites with improved performa

Nanotechnology is a crucial technology in recent years has resulted in new and creative applications of nanomedicine. Polymeric nanoparticles have increasing demands in pharmaceutical applications and require high reproducibility, homogeneity, and control over their properties. Work explores the use of cashew phthalate gum (PCG) as a particle-forming polymer. PCG exhibited a pH-sensitive behavior due to the of acid groups on its chains, and control drug release. We report the development of nanoparticles carrying benznidazole. Formulations were characterized by DLS, encapsulation efficiency, drug loading, FTIR, pH-responsive behavior, release, and in vitro kinetics. Interaction between polymer and drug was an evaluated by molecular dynamics. Morphology was observed by SEM, and in vitro cytotoxicity by MTT assay. Trypanocidal effect for epimastigote and trypomastigote forms was also evaluated. NPs responded to the slightly basic pH, triggering the release of BNZ. In acidic medium, they presented small size, spherical shape, and good stability. It was indicated NP with enhanced biological activity, reduced cytotoxicity, high anti T. cruzi performance, and pH-sensitive release. This work investigated properties related to the development and enhancement of nanoparticles. PCG has specific physicochemical properties that make it a promising alternative to drug delivery, however, there are still challenges to be overcome.