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The diverse applications of nanomaterials, and their rapidly increasing demand, have spurred the development of novel multifunctional materials. As such, this study aimed to synthesize and characterize a magneto-luminescent nanocomposite, composed of magnetite and fluorescent quantum dots (NaGdF4:Nd3+@Fe3O4). Nanomaterial synthesis was accomplished through solvothermal and co-precipitation methods. Stable nanoparticles (NPs) with a zeta potential of -19.57 ± 0.42 mV, and a size of 4.55 ± 1.44 nm were obtained. The crystalline structure of the NPs, verified via x-ray diffraction, affirmed the hexagonal pattern of the NaGdF4:Nd3+NPs and the inverse spinel pattern of Fe3O4NPs. In the diffraction pattern of the NaGdF4:Nd3+@Fe3O4NPs, only the phase pertaining to the Fe3O4NPs was identified, indicating their influence on the nanocomposite. Magnetic measurements revealed the superparamagnetic behavior of the material. Photoluminescence spectra of NaGdF4:Nd3+and NaGdF4:Nd3+@Fe3O4NPs verified the luminescent emission around 1060 nm; a feature of the radiative transitions of Nd3+ions. Based on the assessed characteristics, the nanocomposite's multifunctionality was confirmed, positioning the material for potential use in various fields, such as biomedicine.

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A polyethylene (PE) film surface modification method is proposed via benzoic acid (BA) alkylation grafting to improve the surface affinity to polar substances. The procedure involves sequentially spraying AlCl3 and BA onto the heat-softened PE surface. The occurrence of the alkylation reaction was evaluated through comparative chemical, morphological, and thermal analyses. It was demonstrated that the grafting reaction of BA onto the PE film surface took place, limited to the surface layer, while preserving the bulk properties of PE. The reaction resulted in the formation of aluminum benzoate complexes, which improved the surface affinity to polar compounds. The impact of grafting on the surface properties of PE was further assessed by comparing the behavior of PE films treated with BA and untreated PE films when painted with watercolors. The PE film grafted with BA exhibited increased affinity towards watercolors, providing strong evidence of a change in surface polarity from hydrophobic to hydrophilic. These findings indicate that the proposed methodology effectively renders the PE surface paintable, even with non-toxic water-based inks, making it suitable for applications such as packaging.

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This paper explores the features of both nanoporous and compact TiO2 films formed by titanium anodisation in two experimental conditions, given that they have completely different morphologies and properties than those found by our previous studies. After anodisation, samples have been subjected for 20 days to immersion tests in different media (H2O, H3PO4, and KOH). Surface morphology, phase composition and wettability of anodised films were investigated using FESEM, FTIR, Raman spectroscopy, contact angle measurements and XPS, and the hydrophilicity of modified surfaces was investigated by immersion tests. Nanoporous films exhibited hydrophobic surfaces, but contact angle values gradually decreased after immersing films in H2O, H3PO4 and KOH media, respectively. However, compact films produced superhydrophilic surfaces, both before and after immersion tests, with the exception of immersing the film in a H3PO4 medium due to film removal by acid attack. As for compact films, an unusual morphology revealed by the presence of cone-shaped particles might be responsible for the adsorption of -OH groups arranged so as to favour anatase phase formation.

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Injuries and damage to the skin can be caused by different reasons throughout human life. The use of sodium alginate in tissue dressing has been highly studied due to its intrinsic properties, including its degradation rate and biocompatibility, and the capacity of supporting tissue proliferation. The aim of this paper is to demonstrate evidences, through a systematic review method, to support the application of sodium alginate as a curative and as a potential accelerator in the healing of skin wounds. Four databases were used to develop this systematic review: Science Direct, PubMed, Scielo and Scopus. The time interval established for the search was from January 2016 to October 2023. After applying the exclusion and inclusion criteria, each selected article was evaluated and it was observed that the improvement of the mechanical properties of sodium alginate when correctly processed and crosslinked were evident. However, the increase of crosslinking affects as the wettability and the swelling of the biomaterials can cause limitations in mechanical properties and hidrophilic behavior. To achieve the ideal dressing, it is necessary to apply the optimal concentration of crosslinking and other substances, which can damage its hidrophilic characteristic. Thus, it was concluded that sodium alginate has every caracteristic desirable to develop an effective and safe dressing.

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RESUMO Paciente sexo masculino, 46 anos, portador de ceratocone avançado, evoluiu com hidropsia e perfuração corneana considerada pequena. Inicialmente, foi realizado tamponamento da perfuração com cola de cianoacrilato e lente de contato terapêutica, porém, o ceratocone avançado não permitia estabilização adequada da lente de contato, e o paciente evoluiu com dor intensa, inviabilizando a manutenção da cola de cianoacrilato. Foi indicada, então, a realização de injeção intraestromal de sangue autólogo no centro cirúrgico ambulatorial, que foi efetiva para conter a perfuração. Após melhora do quadro de hidropsia, o paciente foi submetido ao transplante corneano penetrante para reabilitação visual.

ABSTRACT A 46-year-old male who was already diagnosed with keratoconus presented with hydrops followed by a small corneal perforation. At first, the perforation was managed with a cyanoacrylate glue and therapeutic contact lens; however, the advanced keratoconus did not allow stabilization of the contact lens, and the patient developed intense pain, making it impossible to maintain the cyanoacrylate glue. An intrastromal injection of autologous blood was then performed at the operating room, which was effective in containing the perforation. After the hydrops condition improved, the patient underwent penetrating corneal transplantation for visual rehabilitation.

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Abstract The aim of this study was to evaluate the influence of implant macrodesign and surface hydrophilicity on osteoclast (OC) differentiation, activation, and survival in vitro. Titanium disks were produced with a sandblasted, dual acid-etched surface, with or without additional chemical modification for increasing hydrophilicity (SAE-HD and SAE, respectively) and different macrodesign comprising trapezoidal (HLX) or triangular threads (TMX). This study evaluated 7 groups in total, 4 of which were experimental: HLX/SAE-HD, HLX-SAE, TMX/SAE-HD, and TMX/SAE; and 3 control groups comprising OC differentiated on polystyrene plates (CCPC): a positive CCPC (+), a negative CCPC (-), and a lipopolysaccharide-stimulated assay positive control group, CCPC-LPS. Murine macrophage RAW264.7 cells were seeded on the disks, differentiated to OC (RAW-OC) by receptor activator of nuclear factor-κB ligand (RANKL) treatment and cultured for 5 days. Osteoclast differentiation and cell viability were respectively assessed by specific enzymatic Tartrate-Resistant Acid Phosphatase (TRAP) activity and MTT assays. Expression levels of various OC-related genes were measured at the mRNA level by quantitative polymerase chain reaction (qPCR). HLX/SAE-HD, TMX/SAE-HD, and HLX/SAE significantly suppressed OC differentiation when compared to CCPC (+). Cell viability was significantly increased in TMX/SAE and reduced in HLX/SAE-HD. In addition, the expression of Interleukin (IL)-6 and Tumour Necrosis Factor (TNF)-α was upregulated in TMX/SAE-HD compared to CCPC (+). Hydrophilic surfaces negatively modulate macrophage/osteoclast viability. Specifically, SAE-HD with double triangular threads increases the cellular pro-inflammatory status, while surface hydrophilicity and macrodesign do not seem to have a distinct impact on osteoclast differentiation, activation, or survival.

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Marine toxins, produced by various marine microorganisms, pose significant risks to both marine ecosystems and human health. Understanding their diverse structures and properties is crucial for effective mitigation and exploration of their potential as therapeutic agents. This study presents a comparative analysis of two hydrophilic and two lipophilic marine toxins, examining their reactivity properties and bioavailability scores. By investigating similarities among these structurally diverse toxins, valuable insights into their potential as precursors for novel drug development can be gained. The exploration of lipophilic and hydrophilic properties in drug design is essential due to their distinct implications on drug distribution, elimination, and target interaction. By elucidating shared molecular properties among toxins, this research aims to identify patterns and trends that may guide future drug discovery efforts and contribute to the field of molecular toxinology. The findings from this study have the potential to expand knowledge on toxins, facilitate a deeper understanding of their bioactivities, and unlock new therapeutic possibilities to address unmet biomedical needs. The results showcased similarities among the studied systems, while also highlighting the exceptional attributes of Domoic Acid (DA) in terms of its interaction capabilities and stability.

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Microfluidic technology has emerged as a powerful tool for several applications, including chemistry, physics, biology, and engineering. Due to the laminar regime, droplet-based microfluidics enable the development of diverse delivery systems based on food-grade emulsions, such as multiple emulsions, microgels, microcapsules, solid lipid microparticles, and giant liposomes. Additionally, by precisely manipulating fluids on the low-energy-demand micrometer scale, it becomes possible to control the size, shape, and dispersity of generated droplets, which makes microfluidic emulsification an excellent approach for tailoring delivery system properties based on the nature of the entrapped compounds. Thus, this review points out the most current advances in droplet-based microfluidic processes, which successfully use food-grade emulsions to develop simple and complex delivery systems. In this context, we summarized the principles of droplet-based microfluidics, introducing the most common microdevice geometries, the materials used in the manufacture, and the forces involved in the different droplet-generation processes into the microchannels. Subsequently, the encapsulated compound type, classified as lipophilic or hydrophilic functional compounds, was used as a starting point to present current advances in delivery systems using food-grade emulsions and their assembly using microfluidic technologies. Finally, we discuss the limitations and perspectives of scale-up in droplet-based microfluidic approaches, including the challenges that have limited the transition of microfluidic processes from the lab-scale to the industrial-scale.

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ABSTRACT Purpose: To evaluate the efficacy of soft HydroCone silicone hydrogel contact lenses in patients with posterior microphthalmos. Methods: The charts of 13 patients with posterior microphthalmos (26 eyes) who were fitted with soft HydroCone silicone hydrogel contact lenses were reviewed retrospectively. All the patients underwent assessments of uncorrected and best spectacle-corrected visual acuity and cycloplegic refraction. They were fitted with contact lenses according to the parameter values obtained from the topographical analysis and best contact lens-corrected visual acuity measurement. Results: The spherical equivalents of the right and left eyes ranged from 10.00 to 19.25 diopters and from 11.00 to 21.5 diopters, respectively. The mean axial and posterior chamber lengths were shorter than those of the age-matched population. However, the mean values of the anterior segment parameters such as horizontal visible iris diameter, central anterior chamber depth, lens thickness, and central corneal thickness were in the normal range. The mean keratometric measurements revealed increased corneal curvature compared with that in the normal population. The mean best contact lens-corrected visual acuity was significantly higher than the mean best spectacle-corrected visual acuity for both eyes (p=0.045). Conclusion: HydroCone silicon soft contact lenses provided better visual acuity than spectacles in the patients with posterior microphthalmos in this study.

RESUMO Objetivo: Avaliar a eficácia das lentes de contato gelatinosas HydroCone, de hidrogel com silicone, em pacientes com microftalmia posterior. Métodos: Foram revisados retrospectivamente 26 olhos com microftalmia posterior, a partir dos prontuários de 13 pacientes que receberam lentes de contato gelatinosas HydroCone, de hidrogel com silicone. Todos os pacientes foram submetidos ao exame de acuidade visual não corrigida e com melhor correção por óculos e com refração cicloplégica. Todos os pacientes receberam lentes de contato de acordo com os parâmetros obtidos na análise topográfica e foi obtida a melhor acuidade visual corrigida com lentes de contato. Resultados: O equivalente esférico do olho direito variou de 10,00 a 19,25 dioptrias, e o do olho esquerdo de 11,00 a 21,5 dioptrias. Os comprimentos médios axiais e das câmaras posteriores foram menores do que para a população de mesma idade. No entanto, os valores médios dos parâmetros do segmento anterior, como o diâmetro horizontal visível da íris, a profundidade da câmara anterior central, a espessura da lente e a espessura central da córnea estavam dentro da faixa normal. Os valores médios da ceratometria revelaram curvatura corneana aumentada em relação à população normal. A média da melhor acuidade visual corrigida com lentes de contato foi significativamente maior que a média da melhor acuidade visual corrigida com óculos em ambos os olhos (p=0,045). Conclusão: As lentes de contato gelatinosas de silicone HydroCone proporcionam melhor acuidade visual que óculos em pacientes com microftalmia posterior.

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Cationic and hydrophilic coatings based on casting and drying water dispersions of two different nanoparticles (NPs) onto glass are here described and evaluated for antimicrobial activity. Discoid cationic bilayer fragments (BF) surrounded by carboxy-methylcellulose (CMC) and poly (diallyl dimethyl ammonium) chloride (PDDA) NPs and spherical gramicidin D (Gr) NPs dispersed in water solution were cast onto glass coverslips and dried, forming a coating quantitatively evaluated against Pseudomonas aeruginosa, Staphylococcus aureus and Candida albicans. From plating and colony forming units (CFU) counting, all strains interacting for 1 h with the coatings lost viability from 105 to 106, to zero CFU, at two sets of Gr and PDDA doses: 4.6 and 25 µg, respectively, or, 0.94 and 5 µg, respectively. Combinations produced broad spectrum, antimicrobial coatings; PDDA electrostatically attached to the microbes damaging cell walls, allowing Gr NPs interaction with the cell membrane. This concerted action promoted optimal activity at low Gr and PDDA doses. Further washing and drying of the deposited dried coatings showed that they were washed out so that antimicrobial activity was no longer present on the glass surface. Significant applications in biomedical materials can be foreseen for these transient coatings.

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Different drug delivery systems are prepared on the nanoscale to improve performance in drug formulations, such as nanoparticles or nanoemulsions. Polymeric nanoparticles have been used to encapsulate drugs for several applications because of some characteristics of these carriers to control drug delivery, transport molecules to a specific tissue, protect the drugs, and increase drug bioavailability. When using nanocapsules, an essential parameter for encapsulating different hydrophilic or lipophilic molecules is the characteristics of the core. Babassu oil (BBS) is a natural product from Brazil, composed majoritary of short-chain saturated fatty acids. BBS has an elevated hydrophilic-lipophilic balance (HLB), which may promote interaction of the oil with hydrophilic drugs. In this study, we developed and characterized particles containing babassu oil, solely or combined with sorbitan monostearate (Span® 60) or medium chain triglycerides (MCT) in the core to test different HLB and evaluated the encapsulation of a model hydrophilic molecule. Different techniques were used to characterize all formulations in terms of size and distribution, and in vitro drug release by dialysis technique was performed. The BBS was also characterized and presented 46,05 ± 1,11% and 15,38 ± 0,06% of lauric and myristic acid, respectively; saponification index of 248.87 ± 0.64 mg of KOH per gram of BBS, and no oxidation of the oil was indicated by means of peroxide index. Evaporation of solvent carried in the room or reduced pressure influenced the particles' size; nevertheless, all had a z-average smaller than 220 nm. Nanoparticles with a ratio among aqueous phase and organic phase of 2.8 were considered adequate to encapsulate diclofenac sodium. The particles size/zeta potential were 189.83 ± 7.86 nm / - 10.39 ± 2.52 mV, 156.80 ± 4.77 nm / - 9.27 ± 4.61 mV, and 168.87 ± 5.22 nm / - 12.98 ± 4.66 mV to nanoparticles prepared with BBS + MCT, BBS, and BBS + Span® 60, respectively. All formulations exhibited an amount of drug content close to the theoretical amount (1.0 mg mL-1), and no difference was observed in the release profile among the three nanoparticles. Formulation containing only babassu oil in the core displayed 66.78 ± 15.62% of encapsulation efficiency to diclofenac sodium, the highest value among all formulations tested. Results demonstrate that the innovative nanoparticles containing BBS promote the encapsulation of a model hydrophilic molecule, and other components can be evaluated to change the core's hydrophilicity and encapsulation of molecules.

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In this study, graphite, graphene, and hydrophilic-treated graphene electrodes were evaluated in a dual-chamber microbial fuel cell (DC-MFC). Free-oxygen conditions were promoted in anodic and cathodic chambers. Hydrochloric acid at 0.1 M and pH 1.1 was used as a catholyte, in addition to deionized water in the cathodic chamber. Domestic wastewater was used as a substrate, and a DuPontTM Nafion 117 membrane was used as a proton exchange membrane. The maximum power density of 32.07 mW·m-2 was obtained using hydrophilic-treated graphene electrodes and hydrochloric acid as catholyte. This power density was 1.4-fold and 32-fold greater than that of graphene (22.15 mW·m-2) and graphite (1.02 mW·m-2), respectively, under the same operational conditions. In addition, the maximum organic matter removal efficiencies of 69.8% and 75.5% were obtained using hydrophilic-treated graphene electrodes, for hydrochloric acid catholyte and deionized water, respectively. Therefore, the results suggest that the use of hydrophilic-treated graphene functioning as electrodes in DC-MFCs, and hydrochloric acid as a catholyte, favored power density when domestic wastewater is degraded. This opens up new possibilities for improving DC-MFC performance through the selection of suitable new electrode materials and catholytes.

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Pterostilbene (PTS) is a drug candidate with low water solubility and poor bioavailability. On the other hand, drug:cyclodextrins complexes frequently provide bulk powders with low drug concentrations, which is crucial for obtention solid or semi-solid pharmaceutical dosage forms. In order to determine the optimal conditions for enhancing the solubility of PTS:BCD (ß-cyclodextrin) complex, a Box-Behnken design was performed. Although the optimal conditions have been applied, low complexation efficiency (0.127) and the bulk powder remained. A PTS:BCD:HPMC (HPMC, hydroxypropyl methylcellulose) ternary system was developed to overcome this limitation, comparing two media, water and a mixture of ethanol-water. When ethanol was used as a co-solvent, the PTS:BCD:HPMC ternary system (freeze-dried) contained 116.65 ± 1.40 mg/g of PTS. This value was 3.4-fold higher than the PTS content observed when the same ternary system was obtained in aqueous media (34.8 mg/g) and 2.8-fold higher than the PTS content observed for PTS:BCD complex (freeze-dried) obtained using ethanol as a co-solvent. Dissolution tests revealed that after 120 min, in a buffer with a pH value of 1.2, only 43% of PTS dissolved. In contrast, 80% and 90% of PTS were dissolved from the PTS:BCD complex and PTS:BCD:HPMC ternary system, respectively. Moreover, the dissolution was fast in a buffer with a pH value of 6.8. PTS:BCD complex reached the maximum PTS dissolution at 75 min and PTS:BCD:HPMC at 45 min. In summary, the results of this study demonstrated, for the first time, that low-bulk powders with a high content of PTS can be obtained from PTS:BCD:HPMC ternary systems using ethanol as a co-solvent. This new finding offers a valuable alternative for producing solid or semi-solid formulations containing highly soluble PTS.

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Bacteria persisting in environments contaminated with polycyclic aromatic hydrocarbons (PAHs) have developed physiological mechanisms to counteract environmental stress. Inorganic polyphosphate accumulation represents one of these possible mechanisms. Likewise, properties such as cell-surface hydrophobicity, auto-aggregation, biofilm formation and bioemulsifying activity could facilitate interaction of microorganisms with hydrophobic organic compounds. In this work, these physiological properties were compared in indigenous bacteria from polluted sediments from Argentinian Patagonia, which were cultivated in two culture media (LBm and JPP) as a way to improve in the next future the PAHs removal. The highest hydrophobicity values were obtained in Rhodococcus strains, while Bacillus sp. B18 showed the highest auto-aggregation percentage and emulsion index. The highest numerical values of biofilm formation were determined in Rhodococcus sp. F27, Pseudomonas sp. P26, and Gordonia sp. H19 either on hydrophilic or on hydrophobic support. The qualitative and quantitative polyP determinations confirmed the presence of this biopolymer in the strains evaluated. The highest intracellular phosphate mean values were obtained in Bacillus sp. B18 in LBm and Rhodococcus erythropolis 20 in JPP. The bacteria evaluated belonging to different genera showed significant differences in their cell-surface characteristics, bioemulsifying activity and polyP accumulation. The low-cost JPP culture medium was selected for future contaminant removal studies.

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INTRODUCTION: Clean intermittent catheterization (CIC) is associated with an increased risk of urinary tract infections (UTI), urethral trauma, urethral stenosis, hematuria, and pain. The first catheters were developed of polyvinyl carbon (PVC). Several types of catheters have been developed to reduce these complications, such as those with hydrophilic coating. OBJECTIVE: To conduct a systematic review and meta-analysis to evaluate the effectiveness of hydrophilic coated catheters compared to uncoated catheters on the rate of UTI in patients using CIC. METHODOLOGY: A systematic literature search was performed in OVID, Embase, Scopus, Web of Science, PubMed, and CENTRAL databases. Randomized controlled trials (RCTs) or randomized crossover trials comparing UTI and hematuria rates in patients using hydrophilic vs. non-hydrophilic catheters for CIC were identified. The selected trials were evaluated for risk of bias using the "Revised Cochrane risk-of-bias tool for randomized trials (RoB 2)." The results were expressed as a risk ratio (RR) with a 95% confidence interval (CI), under a random-effects model. Data were analyzed using Review Manager 5.4 software. RESULTS: Nine studies with a total of 525 patients in CIC were analyzed. Overall, the use of hydrophilic catheters had a lower risk of UTIs compared to uncoated catheters (RR = 0.78; 95% CI 0.62-0.97; I2 = 37%). Five of the studies include patients > 18 years, showing a reduction of UTIs with the use of hydrophilic catheters (RR = 0.83; 95% CI 0.74-0.93; I2 = 0%). There was no difference in UTI development when comparing single-use uncoated vs hydrophilic catheters. However, heterogeneity was high (RR = 0.77; 95% CI 0.59-1.00; I2 = 57%). Regarding hematuria risk reduction, we were unable to identify differences between the use of hydrophilic catheters compared to uncoated catheters (RR = 1.02; 95% CI 0.66-1.60). CONCLUSION: We found a risk reduction of UTIs associated with using hydrophilic catheters in adults, with low heterogeneity. Regarding hematuria, significant differences were not proved. We do not find a significant difference in UTI risk reduction in the pediatric population. Urethral trauma presence could not be meta-analyzed due to a lack of information reported.

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The global production of cassava was estimated at ca. 303 million tons. Due to this high production, the cassava processing industry (cassava flour and starch) generates approximately ca. 0.65 kg of solid residue and ca. 25.3 l of wastewater per kg of fresh processed cassava root. The composition of the liquid effluent varies according to its origin; for example, the effluent from cassava flour production, when compared to the wastewater from the starch processing, presents a higher organic load (ca. 12 times) and total cyanide (ca. 29 times). It is worthy to highlight the toxicity of cassava residues regarding cyanide presence, which could generate disorders with acute or chronic symptoms in humans and animals. In this sense, the development of simple and low-cost eco-friendly methods for the proper treatment or reuse of cassava wastewater is a challenging, but promising path. Cassava wastewater is rich in macro-nutrients (proteins, starch, sugars) and micro-nutrients (iron, magnesium), enabling its use as a low-cost culture medium for biotechnological processes, such as the production of biosurfactants. These compounds are amphipathic molecules synthesized by living cells and can be widely used in industries as pharmaceutical agents, for microbial-enhanced oil recovery, among others. Amongst these biosurfactants, surfactin, rhamnolipids, and mannosileritritol lipids show remarkable properties such as antimicrobial, biodegradability, demulsifying and emulsifying capacity. However, the high production cost restricts the massive biosurfactant applications. Therefore, this study aims to present the state of the art and challenges in the production of biosurfactants using cassava wastewater as an alternative culture medium.

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The present work aimed to evaluate the healing effect of hydrophilic polymeric resorbable biomembrane scaffolds containing plant extracts obtained from two different species, both popularly known as Stryphnodendron adstringens or Barbatimão. The hydrogel-based scaffolds were characterized and submitted to biological tests using Wistar rats to evaluate their healing capacity. The wound retraction index and the evaluation of the inflammatory process and tissue collagenization were recorded. The extracts showed antioxidant activity with IC50 between 10 and 20 µg/mL (DPPH assay) and 4-6 mmol Trolox/g (FRAP assay). The extract of Stryphnodendron adstringens (SA) presented gallocatechin, epigallocatechin, and O-methylpigalocatechin, while the extract of Abarema cochliacarpa (AC) presented catechin, dimers of procyanidins, di-O-hydroxide, O-deoxyhexosi-hexoside, and epicatechin. The membranes containing SA extract (GELSA) were more rigid, with a more intense color, but less thick, with a more compact structure and few pores. The membranes containing AC extract (GELAC) presented a mechanical profile like the gelatin membrane (GEL), with greater permeability to water vapor. The GELAC and GELSA membranes showed similar thermal degradation profiles. The wounds treated with the membranes containing the extracts obtained high levels of retraction of the wounds with values around 60% and 80% in three and seven days, respectively. These data indicate that the compounds of both species have promising biological activities in the repair process, showing that the extracts accelerated the healing process due to the lower intensity of the inflammatory reaction and the presence of compounds such as catechin and epigallocatechin.

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OBJECTIVES: The aim of this study was to evaluate the influence on MMP inhibition, dentin adhesion and physicochemical properties of an adhesive system incorporated with polymerizable collagen crosslinker monomer derived from cardanol. METHODS: The intermediary cardanol epoxy (CNE) was synthesized through cardanol epoxidation, followed by synthesis of cardanol methacrylate through methacrylic acid solvent-free esterification. Zymographic analysis was performed to evaluate the substances' ability to inhibit gelatinolytic enzymes. Collagen crosslinkers were added into adhesives systems according to the following groups: Ybond Universal® (Control), Ybond® + 2 % proanthocyanidin (PAC), Ybond® + 2 % unsaturated cardanol (Cardanol) and Ybond® + 2 % cardanol methacrylate (CNMA). Degree of conversion (DC) of the adhesives was assessed by FT-IR. Disk-shaped specimens were prepared for water sorption (WS) and solubility (SL) tests. Human third molars were sectioned to expose medium dentin and restored according to the different adhesives used (n = 5). Then, the specimens were cut into 1 mm2 sticks to evaluate, after 24 h and 6-month aging, microtensile bond strength (µTBS) and nanoleakage by scanning electron microscopy. Data were analysed with ANOVA and Tukey's post-test (α = 0.05). RESULTS: CNMA and PAC completely inhibited all forms of gelatinolytic enzymes. Cardanol achieved a significantly lowest DC, while the other groups did not differ from each other (p > 0.05). PAC achieved significantly higher water sorption, while CNMA solubility was significantly lower when compared to the other adhesives (p < 0.05). PAC provided a statistically higher 24 h and 6-month aging bond strength. Intermediary similar µTBS were presented by control and CNMA (p = 0.108). All adhesives applied attained significantly reduced bond strength after aging (p < 0.05). Interfaces created using CNMA were almost devoid of silver deposits initially, however all groups showed large amounts of silver deposits on resin-dentin interface subjected to water aging. SIGNIFICANCE: Although CNMA was effective in inhibiting gelatinolytic enzymes, when incorporated into a universal adhesive it could not promote less degradation of the adhesive interface after water aging. Since it is a hydrophobic monomer, CNMA did not interact well with dentin collagen, however it reduced the solubility of the adhesive system besides not interfering in its polymerization.

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The isolation of pure organic compounds from biological sources, reaction media, or other complex molecular matrixes is the first step to overcome before further biological and chemical investigations. While the isolation of chemicals soluble in organic solvents is commonly accomplished, the isolation of water-soluble organic compounds is less often addressed. We present here a simple method for the isolation of water-soluble organic compounds, using adsorptive macroporous resins and reversed-phase chromatography.

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Flavorings are widely used in food and beverage industries and spray drying is the most cost-effective encapsulation technique to deliver stable products. Generally, the same slurry is used to encapsulate both hydrophilic and hydrophobic flavors which led sometimes to lower retention. The same slurry formulation composed by Modified Starch and Maltodextrin 20DE was loaded with 35% of two different flavorings (orange and passion fruit) and, spray dried under the same conditions. The flavorings selected had different octanol/water partition coefficients and their composition affected the emulsion stability. Orange flavoring presented clearly better emulsion stability than passion fruit flavoring, confirmed by size distribution and Turbiscan Stability Index (TSI orange ≪ TSI passion fruit). A key learning from this work is that the best infeed emulsion achieved by the most hydrophobic flavoring, presented the lowest droplet size and yielded in final bigger particle size and the best encapsulation efficiency result (>92%).