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Alan IS Morais, 1,* Xichi Wang, 2–4,* Ewerton G Vieira, 1 Bartolomeu C Viana, 1, 5 Edson C Silva-Filho, 1 Josy A Osajima, 1 Samson Afewerki, 3, 4 Marcus AF Corat, 6 Heurison S Silva, 5 Fernanda R Marciano, 5 Guillermo U Ruiz-Esparza, 3, 4 Thiago D Stocco, 6, 7 Mirian MM de Paula, 6 Anderson O Lobo 1 1LIMAV-Interdisciplinary Laboratory for Advanced Materials, Materials Science and Engineering Graduate Program, UFPI-Federal University of Piauí, Teresina, PI CEP 64049-550, Brazil; 2Department of Cardiovascular Surgery, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430022, People’s Republic of China; 3Division of Engineering in Medicine, Department of Medicine, Harvard Medical School, Brigham & Women´s Hospital, Cambridge, MA 02139, USA; 4Harvard-MIT Division of Health Science and Technology, Massachusetts Institute of Technology, MIT, Cambridge, MA 02139, USA; 5Department of Physics, UFPI-Federal University of Piauí, Teresina, PI CEP 64049-550, Brazil; 6Multidisciplinary Center for Biological Research, University of Campinas (UNICAMP), Campinas 13083-877, Brazil; 7Faculty of Physiotherapy, Santo Amaro University, São Paulo 04829-300, Brazil*These authors contributed equally to this workCorrespondence: Anderson O Lobo Email lobo@ufpi.edu.brBackground: The facile preparation of oxygen-generating microparticles (M) consisting of Polycaprolactone (PCL), Pluronic F-127, and calcium peroxide (CPO) (PCL-F-CPO-M) fabricated through an electrospraying process is disclosed. The biological study confirmed the positive impact from the oxygen-generating microparticles on the cell growth with high viability. The presented technology could work as a prominent tool for various tissue engineering and biomedical applications.Methods: The oxygen-generated microparticles fabricated through electrospraying processes were thoroughly characterization through various methods such as X-ray diffraction (XRD), Fourier Transform Infrared Spectroscopy (FTIR) analysis, and scanning electron microscopy (SEM)/SEM-Energy Dispersive Spectroscopy (EDS) analysis.Results: The analyses confirmed the presence of the various components and the porous structure of the microparticles. Spherical shape with spongy characteristic microparticles were obtained with negative charge surface (ζ = – 16.9) and a size of 17.00 ± 0.34 μm. Furthermore, the biological study performed on rat chondrocytes demonstrated good cell viability and the positive impact of increasing the amount of CPO in the PCL-F-CPO-M.Conclusion: This technological platform could work as an important tool for tissue engineering due to the ability of the microparticles to release oxygen in a sustained manner for up to 7 days with high cell viability.Keywords: oxygen-generating-microparticles, electrospraying, tissue engineering, calcium peroxide, cartilage

Aila Maria Cipriano Leal,1 Marcus Vinícius Beserra dos Santos,2 Edson Cavalcanti da Silva Filho,2 André Luis Menezes de Carvalho,3 Cinthia Pereira Machado Tabchoury,4 Glauber Campos Vale1 1Department of Restorative Dentistry, Federal University of Piaui, Teresina, Piauí, Brazil; 2Interdisciplinary Laboratory of Advanced Materials, Federal University of Piaui, Teresina, Piauí, Brazil; 3Dermopharmacy Laboratory, Federal University of Piaui, Teresina, Piauí, Brazil; 4Departament of Physiological Sciences, Campinas State University, Piracicaba, São Paulo, BrazilCorrespondence: Glauber Campos ValeDepartment of Restorative Dentistry, Federal University of Piaui, Campus Universitário Ministro Petrônio Portella – SG 10 Bairro Ininga, CEP: 64049-550, Teresina, Piauí, BrazilTel +55 (86) 999912-9200Email glauber@ufpi.edu.brBackground: High-fluoride dentifrice is used to manage root caries, but there is no evidence whether its association with nanohydroxyapatite could provide an additional protection for root caries. Therefore, this study aimed to develop and evaluate the effect of an experimental dentifrice with high fluoride (F−) concentration and nanohydroxyapatite (nano-HA) on root dentin demineralization.Materials and Methods: After formulation of dentifrices, root dentin specimens were randomly assigned to six groups (n = 10) using different dentifrice treatments: placebo; nano-HA without F−; 1,100 μg F−/g; 1,100 μg F−/g + nano-HA; 5,000 μg F−/g; and 5,000 μg F−/g + nano-HA. A pH cycling model was performed for 10 days, in which treatments were performed twice a day. After that period, the longitudinal hardness was evaluated and the area of demineralization (ΔS) was calculated. The formulated dentifrices were evaluated for primary stability, cytotoxicity, and other technical parameters. Two-way ANOVA and Tukey’s test with p set at 5% were used for data analysis.Results: The experimental dentifrices were stable and had no cytotoxicity. Regarding dentin demineralization, the placebo group significantly increased ΔS compared to all other treatment groups (p< 0.001). The dentifrices containing 5,000 μg F−/g, regardless of the presence of nano-HA, led to a smaller lesion area in relation to the other treatments (p< 0.001).Conclusion: The findings of this study suggest that nano-HA reduced dentin demineralization, and dentifrice with 5,000 μg F−/g dentifrices, regardless of the presence of nano-HA, showed a greater reduction in root dentin demineralization.Keywords: material development, dentin, dentifrice, fluoride, nanohydroxyapatite

Bacterial nanocellulose (BNC) has attracted considerable attention in the field of biomedical engineering due to its potential for use in bone regeneration applications. The present study investigates the in vitro and in vivo efficacy of bacterial nanocellulose (BNC) combined with calcium and cerium ions (BNC-Ce:CaP) in bone regeneration applications. XRD analysis confirmed the presence of monetite and hydroxyapatite phases in BNC-CaP, while BNC-Ce:CaP revealed an additional brushite phase. Based on XPS analysis, cerium (III) is found in BNC-Ce:CaP at a concentration of 4.14 % (mol/mol). BNC revealed ultrafine 3D nanofibers with diameters ranging from 20.8 to 53.0 nm, while BNC-Ce:CaP composite, containing cerium, exhibited urchin-like structures with diameters around 1 µm and BNC-CaP composite presented phosphates covering the fiber surfaces, leading to significant thickness increases and pleat formation (70-180 nm). The composite materials demonstrated insignificant cytotoxicity. The results performed by histomorphometric analysis demonstrated that the BNC-Ce:CaP composites showed superior mineralized tissue formation after 60 days. Gene expression revealed a reduction in the inflammatory response and an increase in the expression of osteogenic markers, such as Bmp-2 and Osterix, in addition to an increase in the expression of angiogenic genes, such as Vegf. These findings highlight the potential of BNC-Ce:CaP composites as effective barriers to promote bone regeneration., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2025 Elsevier B.V. All rights reserved.)

Internal curing is a process based on the addition of materials that function as water reservoirs in cementitious media. Superabsorbent hydrogels are an alternative that can be used as an internal curing agent, as they have the ability to absorb and release water in a controlled manner. In the present work, superabsorbent hydrogels based on crosslinked polyacrylamide in the presence of starch and sugarcane bagasse ash (SCBA) were developed and applied to mortars as an internal curing agent. The synthesized hydrogels were evaluated by SEM, FTIR, and swelling analysis. Cement pastes and mortars were produced using different amounts of hydrogel (0.03%, 0.06%, and 0.1% by weight). An analysis of the cement pastes and mortars revealed that hydrogel contributes to hydration, thus improving the quality of the product. Furthermore, the addition of 0.03% hydrogel by weight increased the mechanical resistance of the mortars in up to 26.8% at 28 days of curing as compared with reference (without hydrogel). To the best of our knowledge, this is the first study to use a hydrogel based on polyacrylamide crosslinked with starch and SCBA as a curing agent for mortars and cement pastes. This approach is environmentally friendly, because it uses a natural product (starch) and a byproduct from the sugarcane industry (SCBA).

The continuous increase in bacterial resistance requires the study and development of new biocompatible antibacterial materials. Galactomannan gum was extracted from endosperms of Dimorphandra gardneriana seeds, modified through quaternization reactions (with NaOH/CHPTAC), and evaluated for antimicrobial activity. Four quaternized derivatives were obtained (QG1-QG4). The derivatives were characterized by FTIR, NMR, and rheology, which confirmed the cationization. The galactomannan structure was theoretically studied, and Zeta potential exhibited positive increase in the charge of quaternized derivatives, changing from -3.2 mV (unmodified galactomannan) to +59.35 mV (QG4). Elemental analysis revealed an increase in degree of substitution (DS) between the derivatives, of which QG4 exhibited the highest DS (0.51). QG4 exhibited a bactericidal effect in the antimicrobial test for determination of minimal inhibitory and bactericidal concentrations, against Gram-positive bacteria. Atomic force microscopy showed an increase in bacterial cell surface roughness and decrease in cell height after treatment with QG4. QG3 and QG4 demonstrated antibiofilm potential, showing 50 % and 40 % of inhibition, respectively. After MTT assay, cell viability was maintained approximately 100 % for all derivatives at concentrations of 20 mg/mL on RAW 264.7 macrophages and 86 % with 250 μg/mL on L929 cells. Galactomannan was successfully modified, demonstrating strong antibacterial activity, concomitant to the increase in DS, Zeta potential and reduction of molar mass, with good biocompatibility. Therefore, this study presents a new material with potential for development of formulations for biomedical applications, from industrial waste, strengthening of the D. gardneriana production chain., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024. Published by Elsevier B.V.)

Superabsorbent polymers (PSAs) have been extensively studied to act as internal curing agents in cementitious materials, as they have the characteristic of absorbing and releasing water in a controlled manner, which can contribute to the hydration process of a cementitious medium during its consolidation. Thus, hydrogels consisting of polyacrylamide (PAAm), pectin (Pec) and rice husk ash (RHA) were synthesized to be applied in cementitious matrices. In addition, the PSAs were characterized by FTIR, SEM, and XRD. For evaluating the usage of hydrogels as internal curing agents, different hydrogel contents-0.03, 0.06, and 0.1 (wt-%, relative to cementitious components)-were used for mortar preparation. The mechanical strengths of the cementitious materials were evaluated at day 7 and day 28 during the curing process. The addition of PSAs to the mortars caused an increase in mechanical resistance such that the 0.06% content presented better performance at day 7 of curing (4.07% higher) and at day 28 of curing (8.06% higher) when compared with the reference mortar (without the addition of PSAs) in the same curing periods. This work demonstrates that the addition of PSAs contributes to the hydration of a cementitious material, improving the mechanical resistance of the studied mortars.

Diclofenac is an emerging contaminant widely detected in water and has had adverse effects on the biota. In this study, the adsorbents were prepared by reacting tetradecyl-(C 14 ), hexadecyl-(C 16 ), and octadecyltrimethylammonium (C 18 ) bromides with sodium vermiculite (Na-Ver) and used for the removal of the first time for diclofenac sodium from aqueous solution. Synthesis was carried out in a microwave-assisted reactor operating at 50 °C for 5 min, using proportions of organic salts in 100 and 200% of the phyllosilicate cation exchange capacity. The stability of loaded alkylammonium solids was evaluated under drug adsorption conditions. Adsorption was mainly influenced by the amount of surfactant incorporated into the clay mineral according to the thermogravimetric and CHN elemental analysis data. Samples prepared with 200% CEC presented lower stability at pH 6.0 and 8.0. Drug adsorption was more effective for C 14 -Ver-200%, C 16 -Ver-200%, and C 18 -Ver-200% samples, with a maximum retention of 97.8, 110.1, and 108.0 mg g -1 , respectively. The adsorptive capacities of C 14 -Ver-200%, C 16 -Ver-200%, C 18 -Ver-200%, C 14 -Ver-100%, C 16 -Ver-100%, and C 18 -Ver-100% were reduced to 29.0, 36.8, 41.0, 61.0, 50.4, and 58.0%, respectively, compared with their initial value after three adsorption cycles. X-ray diffraction (XRD) patterns revealed that diclofenac was adsorbed into the interlayer region of organovermiculites. Fourier transform infrared spectroscopy (FTIR), Zeta potential results, and the pH study of adsorption indicated that van der Waals interactions are dominant in the adsorption mechanism., Competing Interests: The authors declare no competing financial interest., (© 2024 The Authors. Published by American Chemical Society.)

In this work, chitosan/collagen-based membranes loaded with 2,3-dihydrobenzofuran (2,3-DHB) were developed through a simple solvent-casting procedure for use in the treatment of cutaneous Leishmaniasis. The obtained membranes were characterized by elemental analysis, FTIR, TG, DSC, and XRD. Porosity, swelling, mechanical properties, hydrophilicity, and antioxidant activity were analyzed. In addition, assessment to the biocompatibility, through fibroblasts/keratinocytes and in vitro wound healing essays were performed. The obtained results show that the new 2,3-DHB loaded chitosan/collagen membrane presented high porosity and swelling capacity as well as maximum strength, hydrophilicity, and antioxidant activity higher in relation to the control. The tests of antileishmanial activity and the AFM images demonstrate great efficacy of inhibition growth of the parasite, superior to those from the standard therapeutic agent that is currently used: Amphotericin B. The new membranes are biocompatible and stimulated the proliferation of keratinocytes. SEM images clearly demonstrate that fibroblasts were able to adhere, maintained their characteristic morphology. The healing test evidenced that the membranes have adequate environment for promoting cell proliferation and growth. As the conventional treatments often use drugs with high toxicity, the as-developed new membranes proved to be excellent candidate to treat cutaneous Leishmaniasis and can be clearly indicated for further advanced studies in vivo., Competing Interests: Declaration of competing interest The authors declare the following financial interests/personal relationships which may be considered as potential competing interests: Edvani Curti Muniz reports financial support was provided by National Council for Scientific and Technological Development. If there are other authors, they declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

Tannins are compounds present in forage plants that, in small quantities in the diet of ruminants, produce protein complexes that promote passage through the rumen and use in the intestine. This study tested the hypothesis that beeswax (BW) and carnauba wax (CW) lipid matrices are effective encapsulants for creating bypass lysine (Lys) for ruminants, with tannin extracted from the Mimosa tenuiflora hay source enhancing material protection. Microencapsulated systems were made using the fusion-emulsification technique with a 2:1 shell-to-core ratio and four tannin levels (0%, 1%, 2%; 3%). The following eight treatments were tested: BWLys 0% , BWLys 1% , BWLys 2% , BWLys 3% , CWLys 0% , CWLys 1% , CWLys 2% , and CWLys 3% . Tannin inclusion improved microencapsulation yield and efficiency. CWLys 3% had the highest microencapsulation efficiency and retained Lys. Lysine in BW and CW matrices showed higher thermal stability than in its free form. Material retention was greater in BW than CW. Rumen pH and temperature remained unaffected, indicating that BW and CW as the shell and tannin as the adjuvant are efficient encapsulants for Lys bypass production. The formulation CWLys 3% is recommended as it is more efficient in protecting the lysin amino acid from rumen degradation.

The presence of drugs in aquatic environments has been considered a global challenge and several remediation technologies have been proposed, including adsorption. In this study, new diclofenac adsorbents were obtained from the reaction of sodium magadiite (Na-Mag) with surfactants dodecylpyridinium chloride hydrate (C 12 pyCl) and hexadecylpyridinium chloride monohydrate (C 16 pyCl)), 1-hexadecyltrimethylammonium bromide (C 16 Br), and dodecyltrimethylammonium bromide (C 12 Br). The synthesis was carried out in the microwave at 50 °C for 5 min using surfactant amounts of 100% and 200% in relation to the cation exchange capacity of Na-Mag. The elemental analysis indicated that surfactants with a longer organic chain were more incorporated into Na-Mag, whose values were 1.42 and 1.32 mmol g -1 for C 16 pyMag200% and C 16 Mag200%, respectively. X-ray diffraction results suggested formation of intercalated products with basal space in the range of 2.81-4.00 nm. Diclofenac was quickly adsorbed on all organophilic magadiites, at an equilibrium time of 1 min. Drug capacity adsorption was influenced by the arrangement and packing density of organic cations, the basal distance, and the organic contents of the samples at high drug concentrations. Alkylpyridinium magadiites exhibited maximum adsorption capacities higher than alkylammonium magadiites, of 96.4, 100.7, 131.7, and 166.1 mg g -1 for C 12 pyMag100%, C 12 pyMag200%, C 16 pyMag100%, and C 16 pyMag200%, respectively, at pH 6.0 and 30 °C. Diclofenac removal by samples was not affected by the presence of ibuprofen, which was also removed from binary system by organophilic magadiites reaching removal of 76.5% and 86.9% by C 16 pyMag100% and C 16 pyMag200%, respectively. Regeneration studies demonstrated a drug removal percentage of 83-92% for C 16 pyMag and C 16 Mag after three cycles of adsorption., (© 2024. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

Hydroxyapatite can combine with polysaccharide originating biomaterials with special applications in the biomedical field. In this review, the synthesis of (nano)composites is discussed, focusing on natural polysaccharides such as alginate, chitosan, and pectin. In this way, advances in recent years in the development of preparing materials are revised and discussed. Therefore, an overview of the recent synthesis and applications of polyssacharides@hydroxyapatites is presented. Several studies based on chitosan@hydroxyapatite combined with other inorganic matrices are highlighted, while pectin@hydroxyapatite is present in a smaller number of reports. Biomedical applications as drug carriers, adsorbents, and bone implants are discussed, combining their dependence with the nature of interactions on the molecular scale and the type of polysaccharides used, which is a relevant aspect to be explored., Competing Interests: The authors declare no competing financial interest., (© 2024 The Authors. Published by American Chemical Society.)

Hydrogels from natural sources are attracting increasing interest due to their ability to protect biologically active molecules. Starch extracted from cassava tubers is a promising material for synthesizing these hydrogels. Copolymerization of cassava gum and incorporation of chlorhexidine digluconate (CLX) into the hydrogels is confirmed by changes in the crystallographic profile, as observed through X-ray diffraction, and a shift in the 1000 cm -1 band in the Fourier-transform infrared spectroscopy spectrum. The differential scanning calorimetry reveals changes in the decomposition temperature of the synthesized hydrogels related to CLX volatility. Micrographs illustrate the material's porosity. Release tests indicate a constant linear release over 72 h, while antimicrobial activity against Staphylococcus aureus, Escherichia coli, and Candida albicans is satisfactory, with 100% effectiveness from 0.5% CLX and the formation of inhibition halos. Toxicity and biocompatibility studies show no cytotoxicity. The continuous release of chlorhexidine is promising for components of biomedical implants and applications as it can ensure antimicrobial action according to specific therapeutic needs., (© 2024 Wiley‐VCH GmbH.)

The insertion of hydrophobic and hydrophilic chains in the chitosan molecule can improve its antibacterial activity, expanding its range of application in several areas of medical-pharmaceutical sciences. Thus, this work aimed to increase the antibacterial activity of chitosan through the modification reaction with phthalic anhydride (QF) and subsequent reaction with ethylenediamine (QFE). The chitosan and derivatives obtained were characterized by elemental analysis, 13 C Nuclear Magnetic Resonance ( 13 C NMR), X-Ray Diffraction (XRD), Fourier Transform Infrared Spectroscopy (FTIR) and Thermogravimetric Analysis (TG), where it was possible to prove the chemical modification. Both materials showed a greater antibacterial inhibitory effect against Gram-positive bacteria, Staphylococcus aureus, emphasizing antibacterial activity against Gram-negative bacteria, Escherichia coli, with values above 70 % of the inhibitory effect, which is a promising result. Assays with human fibroblast cells by the [3-(4,5-dimethylthiazolyl)-2,5-diphenyl tetrazolium (MTT)] bromide reduction test did not indicate toxicity in the materials. Thus, the derived materials showed promise for biomedical applications since they combined excellent antibacterial activity against gram-positive and gram-negative strains and did not show cytotoxicity., Competing Interests: Declaration of competing interest All authors declare that there is no conflict of interest., (Copyright © 2024 Elsevier B.V. All rights reserved.)

Little information is available in the literature on the use of cactus pear meal (CPM) in poultry diets; therefore, it is important to evaluate diets that provide excellent performance and lower production costs. Our objective was to study the use of Miúda CPM in the diets of laying hens. In the first study, two diets for male and female chicks were used-1: 80% reference diet + 20% Miúda cactus pear meal (CPM) and 2: 80% reference diet + 20% Gigante cactus pear meal (CPM). The variety Miúda provided a better use of metabolizable energy, as well as a greater digestibility coefficient of dry matter, protein, and mineral matter. In the second study, a control diet was compared to three diets with different levels of Miúda CPM for laying hens in the proportions of 3%, 6%, and 9%. No significant differences were found in productive performance. However, there were significant differences in the some parameters egg quality, texture and color profile of the cooked yolk, egg composition, fatty acids and cholesterol in the yolk. It is possible to use 9% Miúda CPM in the diet of laying hens in a semi-intensive system that does not compromise performance and egg quality, and using 3% Miúda CPM provides a higher economic return.

The use of hydrogels helpsthe production of plants in drought-stress environments. Thus, this work evaluated using different hydrogels to minimize drought stress in soybean cultivation. The treatments employed two different hydrogels, one already commercialized and the other produced with cashew gum (Anacardium occidentale), five levels (0, 30, 60, 120, and 240 mg pot -1 ) of the hydrogels, and two levels of drought stress in sandy soil. The growth and yield of soybeans and the levels of macro- and micronutrients in soybeans were evaluated.growth. The use of CG hydrogel promoted 12% increase in protein content in the seeds in the when soybean plants were subjected to drought stress. The levels of 30 mg pot -1 , corresponding to 7.5 kg ha -1 , improved the 'morphological and productive parametersof the soybeans. The increasing levels of hydrogel promoted the increase in P, K, Ca, Mg, and Fe and reduced S and Cu on an exponential scale. The use of cashew gum hydrogel increased the K and Ca contents in soybean seeds compared to commercial hydrogel., (© 2024. The Author(s).)

The present work explores the esterification reaction in the polysaccharide extracted from the seaweed Gracilaria birdiae and investigates its antioxidant potential. The reaction process was conducted with phthalic anhydride at different reaction times (10, 20 and 30 min), using a molar ratio of 1:2 (polymer: phthalic anhydride). Derivatives were characterized by FTIR, TGA, DSC and XRD. The biological properties of derivatives were investigated by assays of cytotoxicity and antioxidant activity (2,2-diphenyl-1-picrylhydroxyl - DPPH and 2,2'-azino-bis (3-ethylbenzothiazoline-6-sulfonic acid) diammonium salt - ABTS). The results obtained by FT-IR confirmed the chemical modification, there was a reduction related to the presence of carbonyl and hydroxyl groups when compared to the in nature polysaccharide spectrum. TGA analysis showed a change in the thermal behavior of the modified materials. X-ray diffraction, it was shown that the in nature polysaccharide appeared as an amorphous material, while the material obtained after the chemical modification process had increased crystallinity, due to the introduction of phthalate groups. For the biological assays, it was observed that the phthalate derivative was more selective than the unmodified material for the murine metastatic melanoma tumor cell line (B16F10), revealing a good antioxidant profile for DPPH and ABTS radicals., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023. Published by Elsevier B.V.)

Cashew tree gum is a polysaccharide material highly available in the Northeast region of Brazil. It has been explored for biocompatibility with human tissues. This research aimed to describe the synthesis and characterization of cashew gum/hydroxyapatite scaffold and evaluate the possible cytotoxicity in murine adipose-derived stem cells (ADSCs) cultures. ADSCs of the subcutaneous fat tissue of Wistar rats were collected, isolated, expanded, differentiated into three strains, and characterized immunophenotypically. The scaffolds were synthesized through chemical precipitation, lyophilized and characterized through scanning electron microscopy (SEM), infrared spectroscopy (FTIR), X-ray diffraction (XRD), thermal analysis (TG and DTG), and mechanical testing. The scaffold presented a crystalline structure and pores with an average diameter of 94.45 ± 50.57 μm. By mechanical tests, the compressive force and modulus of elasticity were like the cancellous bone. The isolated adipose-derived stem cells (ADSCs) presented fibroblast morphology, adhesion capacity to plastic, differentiation in osteogenic, adipogenic and chondrogenic lineages, positive expression for the CD105 and CD90 markers and negative expression for the CD45 and CD14 markers. The MTT test showed increased cell viability, and the biomaterial showed a high level of hemocompatibility (<5 %). This study allowed the development of a new scaffold for future surgical applicability in tissue regeneration., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier B.V. All rights reserved.)

Insulin is one of the most important drugs in the clinical treatment of diabetes. There is growing interest in oral insulin administration as it mimics the physiological pathway and potentially reduces side effects associated with subcutaneous injection. In this study, a nanoparticulate system was developed using acetylated cashew gum (ACG) and chitosan by the polyelectrolyte complexation method, for oral administration of insulin. The nanoparticles were characterized by size, zeta potential and encapsulation efficiency (EE%). And they had a particle size of 460 ± 11.0 nm, PDI of 0.2 ± 0.021, zeta potential of 30.6 ± 0.48 mV, and an EE% of 52.5 %. Cytotoxicity assays were performed for HT-29 cell lines. It was observed that ACG and nanoparticles did not have a significant effect on cell viability, verifying their biocompatibility. Hypoglycemic effects of the formulation were analyzed in vivo, noting that the nanoparticles reduced blood glucose by 51.0 % of baseline levels after 12 h, not inducing signs of toxicity or death. Biochemical and hematological profiles were not clinically modified. Histological study indicated no signs of toxicity. Results showed that the nanostructured system presented itself as a potential vehicle for oral insulin release., Competing Interests: Declaration of competing interest The authors report no declarations of interest., (Copyright © 2023. Published by Elsevier B.V.)

The incorporation of polymeric components into aerogels based on clay produces a significant improvement in the physical and thermal properties of the aerogels. In this study, clay-based aerogels were produced from a ball clay by incorporation of angico gum and sodium alginate using a simple, ecologically acceptable mixing method and freeze-drying. The compression test showed a low density of spongy material. In addition, both the compressive strength and the Young's modulus of elasticity of the aerogels showed a progression associated to the decrease in pH. The microstructural characteristics of the aerogels were investigated by X-ray diffraction (XRD) and scanning electron microscopy (SEM). The chemical structure was studied by infrared spectroscopy with Fourier transform (FTIR). The TGA curves from a non-oxidizing atmosphere indicated that the clay had a mass loss of 9% above 500 °C and that due to the presence of polysaccharides, the aerogels presented a decomposition of 20% at temperatures above 260 °C. The DSC curves of the aerogels demonstrated a displacement in higher temperatures. In conclusion, the results showed that aerogels of ball clay with the incorporation of polysaccharides, which are still minimally studied, have potential application as thermal insulation considering the mechanical and thermal results obtained.

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., Competing Interests: Declaration of competing interest The authors have no conflict of interest., (Copyright © 2023 Elsevier B.V. All rights reserved.)

The aim of the present work was to modify the exuded gum of Sterculia striata tree by an amination reaction. The viscosity and zero potential of the chicha gum varied as a function of pH. The modification was confirmed by X-ray diffraction (XRD), infrared spectroscopy (FTIR), size exclusion chromatography (SEC), zeta potential, thermogravimetric analysis (TG), and differential scanning calorimetry (DSC). Furthermore, the chemical modification changed the molar mass and surface charge of the chicha gum. In addition, the gums were used in tests for ex vivo mucoadhesion strength, antibacterial activity against the standard strain of Staphylococcus aureus (ATCC 25923), inhibitory activity of α-glucosidase, antioxidant capacity, and viability of Caco-2 cells. Through these tests, it was found that amination caused an increase in the mucoadhesive and inhibitory activity of chicha gum against the bacterium Staphylococcus aureus. In addition, the gums (pure and modified) showed antioxidant capacity and an inhibitory effect against the α-glucosidase enzyme and did not show cytotoxic potential., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier B.V. All rights reserved.)

A nanocomposite hydrogel has potentially applicability in the induction of osteogenesis. The hydrogel was synthesized using 1% gelatin methacrylate (GelMA), a biodegradable and bioactive polymer containing the structure of gelatin, denatured collagen derived from the extracellular bone matrix, and 6% laponite (Lap), a synthetic phyllosilicate of nanosized particles. Initially, 0.6 g of Lap was added to deionized water, and then a solution of GelMA/Igarcure was added under stirring and UV light for crosslinking. The spectra in the Fourier-transform infrared region showed bands that indicate the interaction between gelatin and methacrylate anhydride. X-ray diffraction patterns confirmed the presence of Lap and GelMA in the hydrogel. The thermogravimetric analysis suggested an increase in the thermal stability of the hydrogel with the presence of clay mineral. Rheological analysis showed that the hydrogel had a viscosity that allowed its injectability. The hydrogel did not show acute toxicity at any of the concentrations tested according to the Artemia salina lethality test. It showed cell viability more significant than 80% in the MTT test, which makes it suitable for in vivo osteogenic induction tests. The cell differentiation test showed the differentiation of stem cells into osteogenic cells. It indicates a material with the potential for osteogenic induction and possible application in bone tissue engineering.

Anthocyanins are one of the natural pigments that humanity has employed the most and can substitute synthetic food dyes, which are considered toxic. They are responsible for most purple, blue, and red pigment nuances in tubers, fruits, and flowers. However, they have some limitations in light, pH, oxygen, and temperature conditions. Combining biomolecules and inorganic materials such as clay minerals can help to reverse these limitations. The present work aims to produce materials obtained using cetyltrimethylammonium bromide in bentonite clay for incorporation and photostabilization of anthocyanin dye. Characterizations showed that the organic molecules were intercalated between the clay mineral layers, and the dye was successfully incorporated at a different pH. Visible light-driven photostability tests were performed with 200 h of irradiation, confirming that the organic-inorganic matrices were efficient enough to stabilize the quinoidal base form of anthocyanin. The pigment prepared at pH 10 was three-fold more stable than pH 4, showing that the increase in the synthesis pH promotes more stable colors, probably due to the stronger intermolecular interaction obtained under these conditions. Therefore, organobentonite hybrids allow to stabilize the fragile color coming from the quinoidal base form of anthocyanin dyes.

The effects of the replacement of dry ground corn (GC) with corn-grain silage rehydrated with water (RCSwater), cactus pear mucilage (RCSmucilage), and whey (RCSwhey) on the growth, physicochemical composition, and fatty acid profile of goat kids’ meat were investigated. Thirty-two crossbred goat kids (16.4 ± 2.50 kg initial weight) were assigned in a randomized block design with four treatments and eight repetitions. The NDF intake of goat kids fed with RCSmucilage was higher in comparison to RCSwater and RCSwhey (p = 0.0009). The dietary replacement of GC by RCSmucilage increased the final weight (p = 0.033) and meat-cooking losses (p = 0.0001) of kids. The concentrations of oleic (p = 0.046), 11,14-eicosadienoic (p = 0.033), and EPA (p = 0.010) were higher in the meat of kids fed with RCSmucilage and RCSwhey, and the α-linolenic concentration was higher (p = 0.019) for animals feeding with RCSmucilage. Meat from kids fed with RCSwhey presented the lowest ∑SFA and the highest ∑MUFA. In contrast, the ∑PUFA (p < 0.012) was higher for goats fed with RCSwater. The ∑ω3 (p < 0.0001) was higher in animals fed with RCSmucilage and RCSwhey. Desirable fatty acids were higher (p = 0.044) in animals fed with RCSmucilage and RCSwhey, and the atherogenicity (p = 0.044) and thrombogenicity (p < 0.0001) indexes were lower for goats fed the RCSwhey diet. The enzymatic activities of Δ9desaturase (C16) were higher (p = 0.027) in goat kids fed with GC and RCSmucilage, and Δ9desaturase (C18) was higher (p = 0.0497) when goats were fed with RCSmucilage and RCSwhey. Elongase activities were higher (p = 0.045) in goat kids fed with GC and RCSwater. The total replacement of GC by RCSmucilage is recommended in the diet of goat kids due to improvements in the weight gain and proportion of desirable fatty acids in the meat. In addition, RCSmucilage promoted better conservation of the silage at a lower cost when compared to commercial additives.

Given the increase in environmental pollution, especially of water, the emergence of studies that seek to develop strategies to mitigate/treat such effects have gained prominence in the world scientific community. Among the numerous adsorption processes, those made from biochar production stand out. This study analyzed the adsorption properties of the blue methylene model dye in the aqueous solution of biochar and activated biochar developed from pequi ( Caryocar brasiliense ) endocarp. The biochar was characterized, before and after adsorption, by infrared spectroscopy (FTIR), scanning electron microscopy (SEM), X-ray diffractometry (XRD), and thermogravimetric analysis (TG). The surface load of the materials was performed by the point of zero charge (pH PZC ) method. The study also included analyses of contact time parameters and adsorbed concentration in the adsorption process. Morphological analysis showed that a more significant and profound number of fissures and pores appeared in the activated biochar compared to the biochar. Residual mass analysis evidenced that biochar lost about 15% more mass than the activated biochar, indicating that activation occurred satisfactorily. The adsorption process was well adjusted by pseudo-second-order kinetics and Langmuir's isothermal model. The activated biochar achieved an excellent adsorption capacity of 476.19 mg.g -1 , thus demonstrating to be a sound system for removing dyes from an aqueous medium.

Gastric ulcer is an injury that develops on the lining of the stomach due to an imbalance between aggressive and defensive agents. Chitosan derivatives demonstrate promising biological activities in accelerating the healing activity of gastric lesions. Thus, this study aimed at investigating the healing activity of gastric lesion, induced by acetic acid (80%), of the chitosan derivative with acetylacetone (Cac) modified with ethylenediamine (Cacen) or diethylenetriamine (Cacdien). The biological activity was determined based on cytotoxicity, antibacterial activity, and gastroprotective activities. The results showed no significant difference in the cytotoxicity, a better antibacterial activity against S. aureus and E. coli , and a positive result on the healing of gastric lesions of the materials (Cac 18.4%, Cacen 55.2%, and Cacdien 68.1%) compared to pure chitosan (50.7%). Therefore, the results indicate that derivatives of chitosan are promising biomaterials for application in the control of lesions on the gastric mucosa., Competing Interests: The authors declare that they have no conflicts of interest., (Copyright © 2022 Leudimar Aires Pereira et al.)

This work reports the functionalization of sodium titanate nanotubes with amine groups obtained from the reaction of titanate nanotubes with [3-(2-Aminoethylamino)propyl]trimethoxysilane, NaTiNT-2NH, and 3-[2-(2-Aminoethylamino)ethylamino]propyltrimethoxysilane, NaTiNT-3NH. It was verified that the crystalline and morphological structures of NaTiNT were preserved after the functionalization, spectroscopies showed that aminosilane interacted covalently with the surface of NaTiNT, and the incorporation of the aminosilane groups on the surface of NaTiNT can be confirmed. The adsorbent matrices NaTiNT-2NH and NaTiNT-3NH were used to remove the anionic dye from remazol blue R (RB) in aqueous medium, and the highest adsorption capacity was around 365.84 mg g-1 (NaTiNT-2NH) and 440.70 mg g-1 (NaTiNT-3NH) in the range of pH 5.0 to 10.0 and the equilibrium time was reached in 210 min (NaTiNT-2NH) and 270 min (NaTiNT-3NH). Furthermore, the Elovich model, which reports the adsorption in heterogeneous sites and with different activation energies in the chemisorption process, was the most appropriate to describe the adsorption kinetics. Thus, these adsorbent matrices can be used as an alternative potential for dye removal RB in aqueous solution.

This review reports recent advances in polysaccharide-based magnetic hydrogels as smart platforms for different biomedical applications. These hydrogels have proved to be excellent, viable, eco-friendly alternative materials for the biomedical field due to their biocompatibility, biodegradability, and possibility of controlling delivery processes via modulation of the remote magnetic field. We first present their main synthesis methods and compare their advantages and disadvantages. Next, the synergic properties of hydrogels prepared with polysaccharides and magnetic nanoparticles (MNPs) are discussed. Finally, we describe the main contributions of polysaccharide-based magnetic hydrogels in the targeted drug delivery, tissue regeneration, and hyperthermia therapy fields. Overall, this review aims to motivate the synthesis of novel composite biomaterials, based on the combination of magnetic nanoparticles and natural polysaccharides, to overcome challenges that still exist in the treatment of several diseases., (Copyright © 2022 Elsevier Ltd. All rights reserved.)

Rigid polyurethane foams were prepared by the one-step expandable foam method using casting molding followed by forming clay-based composites. Polyurethane/vermiculite foam composites (PU/VMT) were controlled based on adding the percentage of clay in the formulation. The effects of composite modifications were evaluated by X-ray diffraction (XRD), thermogravimetric analysis (TG/DTG), and scanning electron microscopy (SEM/EDS) applied to the flame retardancy explored by the vertical burn test. The results indicated that adding clay controlled the particle size concerning polyurethane (PU) foams. However, they exhibited spherical structures with closed cells with relatively uniform distribution. XRD analysis showed the peaks defined at 2θ = 18° and 2θ = 73° relative to the crystallinity in formation and interaction of rigid segments were identified, as well as the influence of crystallinity reduction in composites. In the flame test, the flame retardant surface was successful in all composites, given the success of the dispersibility and planar orientation of the clay layers and the existence of an ideal content of vermiculite (VMT) incorporated in the foam matrix.

Water pollution has generated the need to develop technologies to remove industrial pollutants. Adsorption has been recognized as one of the most effective techniques for effluent remediation. In this study, parts (stem and leaves) of a problematic aquatic weed, the water hyacinth ( Eichhornia crassipes ), were separated to produce a bioadsorbent. The objective was to evaluate the adsorption of a cationic dye, methylene blue (MB), in an aqueous solution of the biomass from different parts of the water hyacinth ( Eichhornia crassipes ) plants. The materials were characterized through techniques of infrared spectroscopy, scanning electron microscopy, X-ray diffractometry, and thermogravimetric analysis, before and after the material adsorption. Water hyacinth biomasses presented adsorption capacity above 89%, and the kinetics was faster for stem biomass. The kinetic study found that the adsorption process is better described by the pseudo-second-order model, and the adjustments of the isotherm experimental data indicated that both materials are favorable for adsorption. Therefore, water hyacinth bioadsorbent represents a renewable resource with potential for effluent treatment.

TiO 2 /Karaya composite was synthesized by the sol-gel method for the photoinactivation of pathogens. This is the first time that we have reported this composite for an antimicrobial approach. The structure, morphology, and optical properties were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), energy dispersive X-rays (EDS), Fourier transform infrared spectroscopy (FTIR), and diffuse reflectance, and the surface area was characterized by the BET method. The XRD and EDS results showed that the TiO 2 /Karaya composite was successfully stabilized by the crystal structure and pore diameter distribution, indicating a composite of mesoporous nature. Furthermore, antibacterial experiments showed that the TiO 2 /Karaya composite under light was able to photoinactivate bacteria. Therefore, the composite is a promising candidate for inhibiting the growth of bacteria.

The present work aimed to characterize the exopolysaccharide obtained from water kefir grains (EPSwk), a symbiotic association of probiotic microorganisms. New findings of the technological, mechanical, and biological properties of the sample were studied. The EPSwk polymer presented an Mw of 6.35 × 10 5 Da. The biopolymer also showed microcrystalline structure and characteristic thermal stability with maximum thermal degradation at 250 °C. The analysis of the monosaccharides of the EPSwk by gas chromatography demonstrated that the material is composed of glucose units (98 mol%). Additionally, EPSwk exhibited excellent emulsifying properties, film-forming ability, a low photodegradation rate (3.8%), and good mucoadhesive properties (adhesion Fmax of 1.065 N). EPSwk presented cytocompatibility and antibacterial activity against Escherichia coli and Staphylococcus aureus. The results of this study expand the potential application of the exopolysaccharide from water kefir as a potential clean-label raw material for pharmaceutical, biomedical, and cosmetic applications.

Herein, a nanocomposite hydrogel was produced using laponite and polyethylene-glycol diacrylate (PEGDA), with or without Irgacure (IG), for application in bone tissue regeneration. The nanocomposites were characterized by X-ray diffraction (XRD), Fourier-Transform infrared spectroscopy (FTIR), and thermal analysis (TG/DTG). The XRD results showed that the crystallographic structure of laponite was preserved in the nanocomposite hydrogels after the incorporation of PEGDA and IG. The FTIR results indicated that PEGDA polymer chains were entangled on laponite in hydrogels. The TG/DTG found that the presence of laponite (Lap) improved the thermal stability of nanocomposite hydrogel. The toxicity tests by Artemia salina indicated that the nanocomposite hydrogels were not toxic, because the amount of live nauplii was 80.0%. In addition, in vivo tests demonstrated that the hydrogels had the ability to regenerate bone in a bone defect model of the tibiae of osteopenic rats. For the nanocomposite hydrogel (PEGDA + Lap nanocomposites + UV light), the formation of intramembranous bone in the soft callus was more intense in 66.7% of the animals. Thus, the results presented in this study evidence that nanocomposite hydrogels obtained from laponite and PEGDA have the potential for use in bone regeneration.

Wounds are considered a clinically critical issue, and effective treatment will decrease complications, prevent chronic wound formation, and allow rapid healing. The development of products based on naturally occurring materials is an efficient approach to wound healing. Natural polysaccharides can mimic the extracellular matrix and promote cell growth, thus making them attractive for wound healing. In this context, the aim of this work was to produce a gel based on chicha gum, chitosan, and Mauritia flexuosa oil (CGCHO) for wound treatment. TG and DTG analyzed the thermal behavior of the materials, and SEM investigated the surface roughness. The percentages of total phenolic compounds, flavonoids, and antioxidants were determined, presenting a value of 81.811 ± 7.257 µmol gallic acid/g Mauritia flexuosa oil, 57.915 ± 0.305 µmol quercetin/g Mauritia flexuosa oil, and 0.379 mg/mL, respectively. The anti-inflammatory was determined, presenting a value of 10.35 ± 1.46% chicha gum, 16.86 ± 1.00% Mauritia flexuosa oil, 10.17 ± 1.05% CGCHO, and 15.53 ± 0.65% chitosan, respectively. The materials were tested against Gram-negative ( Klebsiella pneumoniae ) and Gram-positive ( Staphylococcus aureus ) bacteria and a fungus ( Candida albicans ). The CGCHO formulation showed better antimicrobial activity against Gram-positive bacteria. In addition, an in vivo wound healing study was also performed. After 21 days of treatment, the epidermal re-epithelialization process was observed. CGCHO showed good thermal stability and roughness that can help in cell growth and promote the tissue healing process. In addition to the good results observed for the antimicrobial, antioxidant, anti-inflammatory activities and providing wound healing, they provided the necessary support for the healing process, thus representing a new approach to the wound healing process.

Clay minerals are often used due to their high adsorption capacity, which has sparked interest in their biological applications to stabilize drugs and pharmaceutical products. This research aims to summarize information about the stability of drugs, cosmetics, dermocosmetics, and pharmaceutical compounds incorporated in the structure of different clay minerals. The databases used to search the articles were Web of Science, Scopus, PubMed, and Science Direct. Photostabilization of these compounds is reviewed and its importance demonstrated. For biological applications, the increase in solubility and bioavailability of clay minerals has proven useful for them as drug carriers. While their natural abundance, low toxicity, and accessible cost have contributed to classical applications of clay minerals, a wide range of interesting new applications may be facilitated, mainly through incorporating different organic molecules. The search for new functional materials is promising to challenge research on clay minerals in biological or biotechnological approaches.

Essential oils (EOs) are complex natural mixtures of secondary plant metabolites that function as biocides and therapeutic agents. They are extensively used in bactericidal, virucidal, fungicidal, antiparasitic, insecticidal, pharmaceutical, and cosmetic products. However, certain characteristics, such as the volatility of EOs, hinder their widespread use. To mitigate this limitation, several studies have investigated combinations of EOs with natural materials, including clay minerals. Clay minerals are abundant in nature, biocompatible, and non-toxic to the environment and humans. Clay minerals such as montmorillonite possess available sites where EO molecules can interact. The combination of EOs with clay minerals produces new materials for various applications including antibacterial, antifungal, insecticidal/repellent, and active packaging materials. Therefore, this review focuses on the immobilization of several types of EOs in raw and modified montmorillonites. The applications of the described systems were evaluated and demonstrated the synergism of the properties of the isolated components as a function of different EOs incorporated in the silicate matrix., (Copyright © 2021 Elsevier B.V. All rights reserved.)

The potential use of amino acids by ruminal microorganisms converting them into microbial protein for ruminants makes it challenging to supplement these nutrients in an accessible form in animals' diets. Several strategies to protect amino acids from ruminal degradation were reported, producing amino acids available for the protein used in the intestine called "bypass." The intercalation of biomolecules in clay mineral minerals has gained notoriety due to its ability to support, protect, transport, physicochemical properties and non-toxicity. This study aimed to investigate the incorporation of L-lysine (Lys), L-methionine (Met), and L-tryptophan (Trp) amino acids in the clay minerals sepiolite (Sep) and Veegum ® (Veg) using the adsorption method. The characterization techniques of X-ray diffraction and infrared spectroscopy indicated the presence of biomolecules in the inorganic matrices. Elemental and thermal analyzes monitored the percentages of incorporated amino acids. They showed better incorporation capacities for Veg, such as Met-Veg < Lys-Veg < Trp-Veg and Lys-Sep < Met-Sep < Trp-Sep for sepiolite, except for the incorporation of Met. Matrices provide a promising alternative for planning the administration of biomolecules, using essential amino acids as models, and may offer an alternative to improve functional diet strategies.

The production of edible film from onion ( Allium cepa L.) to be applied as packaging is attractive, due to its chemical properties and biodegradable characteristics. Thus, we tested the hypothesis that edible onion film can positively influence the sensory properties, quality and increasing shelf life of beef burgers patties. The experiment was designed in a 4 × 2 factorial scheme, with two treatments (beef burgers patties with or without edible onion film) at an interval of four storage times (0, 3, 6 and 9 days) at 4 °C. The uncoated burger patties (control) suffered the most intense color modifications during the storage ( p < 0.05). The luminosity index was higher ( p < 0.05) in the control at all storage times, except at day 6, and redness, yellowness and chrome were higher ( p < 0.05) in the edible onion film patties at all storage times. The pH of the beef burger patties was lower ( p < 0.05) at all storage times when the edible onion film was applied. For the texture profile, only the chewiness was affected, as the inclusion of the edible onion film improved the chewing of the beef burgers patties over the storage time ( p < 0.05). Additionally, there was an inhibition of the microbial growth of mesophiles and psychrophiles with the application of the edible onion film in beef burgers patties. The use of edible onion film improved the perception of panelists for the variables texture, color, flavor, odor and overall appearance, and increased the preference of panelists. The edible onion film is recommended for preserving beef burgers patties, as it delays the proliferation of unwanted microorganisms, stabilizes and improves the color parameters and sensory attributes, and increases the overall acceptance of the consumer.

We developed a new hydrophobic polymer based on angico gum (AG), and we produced new nanoparticles to expand the applications of natural polysaccharides in nanomedicine. Phthalate angico gum (PAG) was characterized by 1 H NMR, FTIR, elementary analysis, solubility, XRD, and TG. PAG was a hydrophobic and semi-crystalline material, a relevant characteristic for drug delivery system applications. As a proof of concept, nevirapine (NVP) was selected for nanoparticles development. Plackett-Burman's experimental design was used to understand the influence of several factors in nanoparticles production. PAG proved to be a versatile material for producing nanoparticles with different characteristics. Optimized nanoparticles were produced using desirability parameters. NVP-loaded PAG nanoparticles formulation showed 202.1 nm of particle size, 0.23 of PDI, -17.1 of zeta potential, 69.8 of encapsulation efficiency, and promoted modified drug release for 8 h. Here we show that PAG presents as a promising biopolymer for drug delivery systems., (Copyright © 2021. Published by Elsevier B.V.)

Ibuprofen (IBU) is one of the most-sold anti-inflammatory drugs in the world, and its residues can reach aquatic systems, causing serious health and environmental problems. Strategies are used to improve the photocatalytic activity of zinc oxide (ZnO), and thosethat involvethe inclusion of metalhave received special attention. The aim of this work was to investigate the influence of the parameters and toxicity of a photoproduct using zinc oxide that contains cerium (ZnO-Ce) for the photodegradation of ibuprofen. The parameters include the influence of the photocatalyst concentration (0.5, 0.5, and 1.5 g L -1 ) as well as the effects of pH (3, 7, and 10), the effect of H 2 O 2 , and radical scavengers. The photocatalyst was characterized by Scanning Electron Microscopy-Energy Dispersive Spectroscopy, Transmission electron microscopy, Raman, X-Ray Diffraction, surface area, and diffuse reflectance. The photocatalytic activity of ibuprofen was evaluated in an aqueous solution under UV light for 120 min. The structural characterization by XRD and SEM elucidated the fact that the nanoparticle ZnO contained cerium. The band gap value was 3.31 eV. The best experimental conditions for the photodegradation of IBU were 60% obtained in an acidic condition using 0.50 g L -1 of ZnO-Ce in a solution of 20 ppm of IBU. The presence of hydrogen peroxide favored the photocatalysis process. ZnO-Ce exhibited good IBU degradation activity even after three photocatalytic cycles under UV light. The hole plays akey role in the degradation process of ibuprofen. The toxicity of photolyzed products was monitored against Artemia salina (bioindicator) and did not generate toxic metabolites. Therefore, this work provides a strategic design to improve ZnO-Ce photocatalysts for environmental remediation.

The incorporation of drugs in nanocomposites can be considered a potential strategy for controlled drug release. In this study, a nanocomposite based on bacterial cellulose and the palygorskite clay (BC/PLG) was produced and loaded with metronidazole (MTZ). The samples were characterized using X-ray diffraction (XRD) Spectroscopy, thermal analysis (TG/DTG) and Scanning Electron Microscopy (SEM). The barrier properties were determined to water vapor permeability (WVP). Adsorption tests with PLG were performed using MTZ and drug release profile of the membranes was investigated. The results indicated that PLG increased the crystallinity of the nanocomposites, and greater thermal stability when PLG concentration was 15.0% (BC/PLG15) was observed. WVP of the samples also varied, according to the clay content. Adsorption equilibrium was achieved from 400 mg/L of the PLG and a plateau in the MTZ release rates from BC/PLG was observed after 30 min. Therefore, the results of this study show the potential of these nanocomposite membranes as a platform for controlled drug release., (Copyright © 2021 Elsevier B.V. All rights reserved.)

Agricultural production is influenced by the water content in the soil and availability of fertilizers. Thus, superabsorbent hydrogels, based on polyacrylamide, natural cashew tree gum (CG) and potassium hydrogen phosphate (PHP), as fertilizer and water releaser were developed. The structure, morphology, thermal stability and chemical composition of samples of polyacrylamide and cashew tree gum hydrogels with the presence of fertilizer (HCGP) and without fertilizer (HCG) were investigated, using X-ray diffractometry (XRD), Fourier Transformed Infrared Spectroscopy (FTIR), Scanning Electron Microscopy (SEM), Thermogravimetric Analysis (TGA/DTG) and Energy Dispersive Spectroscopy (EDS). Swelling/reswelling tests, textural analysis, effect of pH, release of nutrients and kinetics were determined; the ecotoxicity of the hydrogels was investigated by the Artemia salina test. The results showed that PHP incorporation in the hydrogel favored the crosslinking of chains. This increased the thermal stability in HCGP but decreased the hardness and adhesion properties. The HCGP demonstrated good swelling capacity (~15,000 times) and an excellent potential for reuse after fifty-five consecutive cycles. The swelling was favored in an alkaline pH due to the ionization of hydrophilic groups. The sustained release of phosphorus in HCGP was described by the Korsmeyer-Peppas model, and Fickian diffusion is the main fertilizer release mechanism. Finally, the hydrogels do not demonstrate toxicity, and HCGP has potential for application in agriculture.

Herbicides are hazardous organic pollutants that contribute to the risk of environmental contamination. The aim of this work was to investigate the synergistic effect of silver (Ag) and gold (Au) bimetallic nanoparticles deposited on palygorskite (PAL) in the presence of TiO 2 for photodegradation of bentazone (BTZ) herbicide under UV light. Ag and Au@Ag nanoparticles exhibited an average size below 75 nm and surface charge values less than - 30 mV. UV-Vis spectroscopy indicates the formation of core@shell bimetallic nanoparticles. XRD results showed the interactions between the NPs and the palygorskite structure. SEM images clearly illustrate the presence of small spherical particles distributed in the clay fibers. The control of the size and distribution of the nanoparticles played an important role in the properties of the composites. The degradation of the herbicide BTZ showed that nanoparticles, clay, and only TiO 2 did not produce satisfactory results; however, when Ag-Pal and Au@Ag-Pal were in the presence of the TiO 2 , the degradation was efficient. The best photodegradative system was Au@Ag-Pal+TiO 2 , which was maintained after the third cycle. The bentazone photodegradation using Au@Ag-PAL+TiO 2 exhibited toxicity against Artemia salina. Therefore, Au@Ag-PAL+TiO 2 photocatalyst showed that the synergy of bimetallic nanoparticles deposited on clay for enhanced photodegradation activity of bentazone herbicide.

Molybdates are biocidal materials that can be useful in coating surfaces that are susceptible to contamination and the spread of microorganisms. The aim of this work was to investigate the effects of copper doping of hydrated cobalt molybdate, synthesized by the co-precipitation method, on its antibacterial activity and to elucidate the structural and morphological changes caused by the dopant in the material. The synthesized materials were characterized by PXRD, Fourier Transformed Infrared (FTIR), thermogravimetric analysis/differential scanning calorimetry (TG/DSC), and SEM-Energy Dispersive Spectroscopy (SEM-EDS). The antibacterial response of the materials was verified using the Minimum Inhibitory Concentration (MIC) employing the broth microdilution method. The size of the CoMoO 4 ·1.03H 2 O microparticles gradually increased as the percentage of copper increased, decreasing the energy that is needed to promote the transition from the hydrated to the beta phase and changing the color of material. CoMoO 4 ·1.03H 2 O obtained better bactericidal performance against the tested strains of Staphylococcus aureus (gram-positive) than Escherichia coli (gram-negative). However, an interesting point was that the use of copper as a doping agent for hydrated cobalt molybdate caused an increase of MIC value in the presence of E. coli and S. aureus strains. The study demonstrates the need for caution in the use of copper as a doping material in biocidal matrices, such as cobalt molybdate.

Chemical modification of polysaccharides is an important approach for their transformation into customized matrices that suit different applications. Microwave irradiation (MW) has been used to catalyze chemical reactions. This study developed a method of MW-initiated synthesis for the production of phthalated cashew gum (Phat-CG). The structural characteristics and physicochemical properties of the modified biopolymers were investigated by FTIR, GPC, 1 H NMR, relaxometry, elemental analysis, thermal analysis, XRD, degree of substitution, and solubility. Phat-CG was used as a matrix for drug delivery systems using benznidazole (BNZ) as a model drug. BNZ is used in the pharmacotherapy of Chagas disease. The nanoparticles were characterized by size, PDI, zeta potential, AFM, and in vitro release. The nanoparticles had a size of 288.8 nm, PDI of 0.27, and zeta potential of -31.8 mV. The results showed that Phat-CG has interesting and promising properties as a new alternative for improving the treatment of Chagas disease., (Copyright © 2020 Elsevier Ltd. All rights reserved.)

Recently, zinc-based materials have gained immense attention as antimicrobial agents. In this study, zinc-doped mesoporous hydroxyapatites (HAps) with various Zn contents were prepared by co-precipitation using a phosphoprotein as the porous template. The use of the phosphoprotein as the porous template resulted in the formation of zinc-doped mesoporous HAps (mHAps) with large pores and specific surface area (182 m 2 g -1 ), as indicated by the nitrogen adsorption/desorption measurements. The formation of the zinc-doped HAps was confirmed by various analytical techniques such as X-ray diffraction, Fourier transform infrared spectroscopy, transmission electron microscopy, and X-ray photoelectron spectroscopy. The biomaterials prepared in this study were used as antimicrobial agents against gram-positive (Staphylococcus aureus) and gram-negative (Escherichia coli) bacteria. The Zn2%-mHAp sample showed the maximum bacterial inhibitory concentrations of 50 ± 5% and 77 ± 5% for the Gram-positive and Gram-negative bacteria, respectively. The antibacterial activity of the mHAp samples depended strongly on their Zn 2+ content. Thus, the use of a biotemplate and Zn 2+ ions is an efficient approach for the formation of novel HAp-based biomaterials with promising antibacterial properties. This synthesis approach will pave a new pathway for the functionalization of other materials for different biomedical applications., (Copyright © 2020 Elsevier B.V. All rights reserved.)

A biomineralization processes is disclosed for engineering nanomaterials that support bone repair. The material was fabricated through a hot press process using electrospun poly(lactic acid) (PLA) matrix covered with hybrid composites of carbon nanotubes/graphene nanoribbons (GNR) and nanohydroxyapatite (nHA). Various scaffolds were devised [nHA/PLA, PLA/GNR, and PLA/nHA/GNR (1 and 3%)] and their structure and morphology characterized through Scanning electron microscopy (SEM), Energy dispersive X-ray spectroscopy (EDS), and Atomic force microscope (AFM). Moreover, thorough biocompatibility and toxicity studies were performed. Here, in vivo studies on toxicity and cytotoxicity were conducted in aqueous dispersions of the biomaterials at concentrations of 30, 60, and 120 μg/mL using the Allium cepa test. Further toxicity studies were performed through hemolysis toxicity tests and genotoxicity tests evaluating the damage index and damage frequencies of DNAs through comet assays with samples of the animals' peripheral blood, marrow, and liver. Additionally, the regenerative activity of the scaffolds was analyzed by measuring the cortical tibiae of rats oophorectomized implanted with the biomaterials. Biochemical analyzes [glutamic pyruvic transaminase (GPT), glutamic oxaloacetic transaminase (GOT), urea, calcium, phosphorus, and alkaline phosphatase (ALP)] were also performed on blood samples. The results suggested a toxicity and cytotoxicity level for the GNR biomaterials at a concentration of 60 and 120 μg/mL, but non-toxicity and cytotoxicity for the 30 μg/mL concentration. The scaffolds obtained at a concentration of 0.3 mg/cm 2 were not toxic in the hemolysis test and demonstrated no cytotoxicity, genotoxicity, and mutagenicity in the blood, marrow, and liver analyzes of the animals, corroborating data from the biochemical markers of GPT, GOT, and urea. Tissue regeneration was performed in all groups and was more pronounced in the group containing the combination of nHA/GNR (3%), which is consistent with the data obtained for the calcium, serum phosphorus, and ALP concentrations. Consequently, the study indicates that the engineered nanobiomaterial is a promising candidate for bone tissue repair and regenerative applications. STATEMENT OF SIGNIFICANCE: The scientific contribution of this study is the engineering of a synthetic hybrid biomaterial, in nanoscale by a pressing and heating process. A biodegradable polymeric matrix was covered on both sides with a carbonated hybrid bioceramic/graphene nanoribbons (GNR), which has hydrophilic characteristics, with chemical elements stoichiometrically similar to bone mineral composition. The nanomaterial displayed promising bone regeneration ability, which is the first example to be used in an osteoporotic animal model. Moreover, detailed biocompatibility and toxicity studies were performed on the nanomaterials and their compositions, which is of great interest for the scientific community., (Copyright © 2020 Elsevier B.V. All rights reserved.)

The objective of this research was to modify chicha gum with phthalic anhydride to obtain a new biologically active material. The chemical modification of the gum structure was proven through FTIR, elemental analysis, XRD, TG, and DSC. The derived materials demonstrated excellent inhibitory effect against P. aeruginosa and K. pneumoniae species (rating 100% inhibition) and could also inhibit Escherichia coli growth. The best antimicrobial activity observed for the derivatives suggests that chicha gum hydrophobization due to the addition of phthalic groups improved the interaction of these derivatives with bacterial cell wall components. On the other hand, the derivatives increased CC 50 in macrophages but did not present acute toxicity or hemolytic activity, indicating that they are promising for use in prophylaxis or treatment of infections caused by Gram-negative bacteria., (Copyright © 2020 Elsevier Ltd. All rights reserved.)

Flowers-like ZnO structures were synthesized using Arabic Gum (AGZnO) or Karaya Gum (KGZnO). The AGZnO and KGZnO were characterized by X-ray diffractometry, Fourier Transformed Infrared, Scanning Electron Microscopy, Photoluminescence, nitrogen adsorption/desorption and diffuse reflectance techniques. The materials were tested in the discoloration of Methylene Blue (MB) dye under visible light and scavenger studies were also performed. The toxicity of the MB irradiated was investigated in bioassays with Artemia salina. The structural characterization demonstrated the formation of hexagonal ZnO. All samples presented flower-like morphology with presence of mesopores identified by BET method. The optical properties indicated band gap of 2.99 (AGZnO) and 2.76 eV (KGZnO), and emission in violet, blue and green emissions also were observed. The KGZnO demonstrated better photocatalytic performance than the AGZnO, and scavenger studies indicated that OH radicals are the main species involved in the degradation of the pollutant model. The photodiscoloration of MB solution did not demonstrate toxicity. Therefore, KGZnO is a promising material for photocatalysis application., (Copyright © 2020 Elsevier B.V. All rights reserved.)

Natural polysaccharides have been investigated as vehicles for oral insulin administration. Because of their non-toxic, renewable, low cost and readily available properties, gums find multiple applications in the pharmaceutical industry. This work aimed to develop a Sterculia striata gum-based formulation associated with additional biopolymers (dextran sulfate, chitosan, and albumin), a crosslinking agent (calcium chloride) and stabilizing agents (polyethylene glycol and poloxamer 188), to increase the oral bioavailability of proteins. Insulin was used as a model drug and the methods used to prepare the formulation were based on ionotropic pregelation followed by electrolytic complexation of oppositely charged biopolymers under controlled pH conditions. The developed formulation was characterized to validate its efficacy, by the determination of its average particle size (622 nm), the insulin encapsulation efficiency (70%), stability in storage for 30 days, and the in vitro mucoadhesion strength (92.46 mN). Additionally, the developed formulation preserved about 64% of initial insulin dose in a simulated gastric medium. This study proposed, for the first time, a Sterculia striata gum-based insulin delivery system with potential for the oral administration of protein drugs, being considered a valid alternative for efficient delivery of those drugs., (Copyright © 2020 Elsevier B.V. All rights reserved.)