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We have studied repositioning of carvedilol (an antihypertensive drug) incorporated into MCM-41 mesoporous silica. The repositioning proposes a reduction in the slow pace of discovery of new drugs, as well as toxicological safety and a significant reduction in high research costs, making it an attractive strategy for researchers and large pharmaceutical companies. We obtained MCM-41 by template synthesis and functionalized it by post-synthesis grafting with aminopropyltriethoxysilane (APTES) only or with folic acid (FA), which gave MCM-41-APTES and MCM-41-APTES-FA, respectively. We characterized the materials by scanning and transmission electron microscopy, zeta potential (ZP) measurements, Fourier transform infrared absorption spectroscopy, x-ray diffractometry, nitrogen gas adsorption, and CHNS elemental analysis. We quantified the percentage of drug that was incorporated into the MCM-41 materials by thermogravimetric analysis and evaluated their cytotoxic activity in non-tumor human lung fibroblasts and the tumor human melanoma and human cervical adenocarcinoma cell lines by XTT salt reduction (2,3-bis-(2-methoxy-4-nitro-5-sulfophenyl)-2H-tetrazolium-5-arboxanilide). The x-ray diffractograms of the MCM-41 materials displayed low-angle peaks in the 2 θ range between 2° and 3°, and the materials presented type IV nitrogen adsorption isotherms and H2 hysteresis typical of the MCM-41hexagonal network. The infrared spectra, the charge changes revealed by ZP measurements, and the CHN ratios obtained from elemental analysis showed that MCM-41 was amino-functionalized, and that carvedilol was incorporated into it. MCM-41-APTES incorporated 23.80% carvedilol, whereas MCM-41 and MCM-41-APTES-FA incorporated 18.69% and 12.71% carvedilol, respectively. Incorporated carvedilol was less cytotoxic to tumor and non-tumor cells than the pure drug. Carvedilol repositioning proved favorable and encourages further studies aimed at reducing its cytotoxicity to non-tumor cells. Such studies may allow for larger carvedilol incorporation into drug carriers or motivate the search for a new drug nanocarrier to optimize the carvedilol antitumoral activity., (© 2024 IOP Publishing Ltd. All rights, including for text and data mining, AI training, and similar technologies, are reserved.)

Enhancing the initial stages of plant growth by using polymeric gels for seed priming presents a significant challenge. This study aimed to investigate a microgel derived from polyetheramine-poly(propylene oxide) (PPO) and a bisepoxide (referred to as micro-PPO) as a promising alternative to optimize the seed germination process. The micro-PPO integrated with an iron micronutrient showed a positive impact on seed germination compared with control (Fe solutions) in which the root length yield improved up to 39%. Therefore, the element map by synchrotron-based X-ray fluorescence shows that the Fe intensities in the seed primers with the micro-PPO-Fe gel are about 3-fold higher than those in the control group, leading to a gradual distribution of Fe species through most internal embryo tissues. The use of micro-PPO for seed priming underscores their potential for industrial applications due to the nontoxicity results in zebrafish assays and environmentally friendly synthesis of the water-dispersible monomers employed.

This paper presents the influence of the presence of a modified organoclay, Cloisite ® 20A (MMTA) on the structural and drug release properties of ureasil organic-inorganic hybrid. Sol-gel process was used to prepare the hybrid nanocomposites containing sodium diclofenac (DCF) at 5% wt. The effect of the amount of MMTA incorporated into the ureasil hybrid matrix was evaluated and characterized in depth by different techniques such as X-ray diffraction (XRD), small angle X-ray scattering (SAXS), differential scanning calorimetry (DSC), and swelling properties. The influence of MMTA on ureasil nanocomposites release profile was evaluated by in situ UV-vis. The diffraction patterns of the UPEO-MMTA nanocomposites showed a synergistic contribution effect that led to an intensity increase and narrowed the diffraction peaks, evidencing a crystallite PEO growth as a function of the modified nanoclay content. The interactions between polyether chains and the hydrogenated tallow of MMTA led to an easy intercalation process, as observed in UPEO-MMTA nanocomposites containing low (1% wt) or high (20% wt) nanoclay content. The waterway (channels) created in UPEO-MMTA nanocomposites contributed to a free volume increase in the swollen network compared to UPEO without MMTA. The hypothesis of the channels created after intercalation of the PEO phase in the interlayer of MMTA containing organoammonium ions corroborates with the XRD results, swelling studies by SAXS, and release assays. Furthermore, when these clay particles were dispersed in the polymeric matrix by an intercalation process, water uptake improvement was observed, with an increased amount of DCF release. The design of ureasil-MMTA nanocomposites containing modified nanoclay endows them with tunable properties; for example, swelling degree followed by amount of controlled drug release, opening the way for more versatile biomedical applications.

As an archipelago, the Philippines is heavily engaged in domestic and foreign shipping activities which makes it highly vulnerable to oil pollution. It is the purpose of this present paper to make a follow-up review of the oil spill situation in the Philippines which provides analysis and evaluation of aquatic oil spills in the past 22 years. Results showed that the frequency and volume of oil spills generally occur in areas with high maritime traffic and experienced short-term decreases on periods affected by economic recessions. The sources and causes of oil spills are discussed while examining the possible influences of the changing climate. While, these had been identified, there is a gap in the incident reporting of oil spills. It is recommended that data records on oil spill incidents in the Philippines be systematic, consistent and comprehensively entail information not limited to date, locality, source, cause, and spillage amount., 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 © 2022 Elsevier Ltd. All rights reserved.)

Lignan dinitrohinokinin displays important biological activities, which led to the preparation of its poly-ε-caprolactone nanoparticles. Kinetics analysis revealed initially slow drug release followed by a prolonged, moderate release 6 h later due to DNHK diffusion through the polymeric matrix. Molecular dynamics simulations show that DNHK molecules that interact stronger with other DNHK molecules near the PCL/DNHK surface are more difficult to dissociate from the nanoparticle. The smaller diameter nanocapsules with negative surface charge conferred good colloidal stability. The formulations showed a size distribution with monodisperse systems formation. In vivo evaluation of schistosomicidal activity against Schistosoma mansoni showed that DNHK, when incorporated into nanoparticles, caused egg number reduction of 4.2% and 28.1% at 40 mg/kg and 94.2% and 84.4% at 400 mg/kg in the liver and the spleen, respectively. The PCL nanoparticles were stable in aqueous dispersion and could be optimized to be used as a promising lignan release agent.

Schistosomiasis mansoni is an infectious parasitic disease caused by worms of the genus Schistosoma, and praziquantel (PZQ) is the medication available for the treatment of schistosomiasis. However, the existence of resistant strains reinforces the need to develop new schistosomicidal drugs safely and effectively. Thus, the (±)-licarin A neolignan incorporated into poly-Ɛ-caprolactone (PCL) nanoparticles and not incorporated were evaluated for their in vivo schistosomicidal activity. The (±)-licarin A -loaded poly(ε-caprolactone) nanoparticles and the pure (±)-licarin A showed a reduction in the number of worm eggs present in spleens of mice infected with Schistosoma mansoni. In addition, the (±)-licarin A incorporated in the concentration of 20 mg/kg and 200 mg/kg reduced the number of worms, presenting percentages of 56.3% and 41.7%, respectively., 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 © 2022 Elsevier Inc. All rights reserved.)

This work aimed to synthesize poly (D, L-lactic-co-glycolic acid) (PLGA) microparticles containing hinokinin (HNK) and to evaluate their cytotoxic activity against tumoral SiHa cells and non-tumoral HaCaT cells. Hinokinin was incorporated into PLGA (PLGA-HNK) with an encapsulation efficiency of 84.18 ± 2.32%. PLGA and PLGA-HNK were characterized by SEM microscopy and showed spherical morphology with an average size of ∼3.33. Encapsulation efficiency was determined by a calibration curve using UV-vis spectroscopy. PLGA-HNK more active inhibiting proliferation of SiHa cells (IC 50 = 14.68 µM) than free HNK (IC 50 = 225.5 µM). In relation to HaCaT cells, PLGA-HNK showed no significant difference compared to the negative control. These results led to an increase in HNK bioavailability and thereby, biological activity. In silico prediction analysis suggests that HNK is cytotoxic against SiHa cells with E6 and MDM2 inhibition as possible main mechanism of action.

Here, we demonstrate a facile and scalable preparation via sol-gel chemistry of hybrid polyurea gels containing various amounts of a phosphorescent inorganic octahedral molybdenum cluster-based ternary salt, namely Cs2Mo6Br14. The influence of the Cs2Mo6Br14 content (1-10 wt%) on the polyurea matrix and its physical properties are studied in depth by Fourier transform infrared spectroscopy (FTIR), differential scanning calorimetry (DSC) and X-ray fluorescence microanalysis (μ-XRF). Regardless of the amount of cluster loaded into the polyurea, the integrity of these species was preserved and their dispersion is homogeneous as shown by μ-XRF mapping. Spectroscopic-structural analyses reveal a significant increase of the chain mobility (glass transition temperature Tg) from -65 °C to -55 °C after the incorporation of Cs2Mo6Br14 (DSC analyses). The FTIR studies show that the homogeneity of the dispersion is ensured by supramolecular interactions between the ether-type oxygen atoms of the PEO chains and the cluster compound. Photoluminescence studies show that the metal cluster emission properties are well retained within the host matrix whatever the loaded content. Such a combination of materials demonstrates the feasibility to fabricate a rubber NIR-emitting device. Moreover, the loaded polyurea is also able to produce reactive oxygen species (ROS) upon irradiation in the UV-A region, opening new perspectives as versatile membranes in the field of photodynamic therapy.

In this study, the trypomastigotes of a Y strain of Trypanosoma cruzi were inoculated intraperitoneally into male BALB/c mice weighing approximately 25 g each, which were divided into groups for evaluation of the trypanocidal activity. For the treatment of experimental groups, encapsulated and unencapsulated (-)-cubebin, Benznidazole, and two groups as negative controls were used. The encapsulated (-)-cubebin showed a 68.1 % encapsulation efficiency. The parasitemia peak of substances remained around the 9 th day after the observed reduction in the number of circulating trypomastigotes. The encapsulated (-)-cubebin and (-)-cubebin unloaded showed a decrease of 61.3 % and 58.5 % in the number of parasites as compared to the negative control, respectively. Moreover, animals treated with encapsulated (-)-cubebin had a higher survival time as compared to the other groups. In conclusion, the results obtained were more promising for encapsulated (-)-cubebin as compared to unloaded particles., (© 2021 Wiley-VHCA AG, Zurich, Switzerland.)

There continues to be a need to develop controlled-release systems loaded with multiple drugs with distinct pharmacological activities, such as anti-inflammatory and anticancer effects, which are able to provide the desired release of each drug, as a function of time. To this end, an elegant strategy was developed for the incorporation, in a one-step process, of the anti-inflammatory drug naproxen (NAP) and the anticancer drug 5-fluorouracil (5FU) into a ureasil organic-inorganic hybrid matrix. A ureasil-poly(oxyalkylene) (UPEO) matrix was prepared using a sol-gel route to obtain a versatile dual-drug delivery system. Small-angle X-ray scattering (SAXS) measurements and Fourier transform infrared spectroscopy (FTIR) demonstrated that the UPEO network is preserved upon loading with the two drugs NAP and 5FU. There was excellent agreement between the macroscopic swelling behavior (water uptake) and surface wettability (determined using contact angle measurements), with this behavior being closely correlated with the release profiles and playing an important role in the sustained delivery of both drugs from the hybrid matrix. The amounts of both drugs released simultaneously could be finely controlled by adjusting the pH of the aqueous medium, with the release presenting stimulus-responsive behavior. In an aqueous PBS medium, the dual-UPEO-release system presented excellent potential as a vehicle for the release of the water-soluble 5FU and water-insoluble NAP drugs, at identical rates, using a single carrier. This novel and adjustable dual-drug delivery UPEO system is a promising hybrid material carrier with the ability to simultaneously incorporate a wide range of therapeutic agents for the treatment of various diseases, including cancers.

In this work, we have investigated how the concentration of Gd 3+ ions affects the structural and luminescent properties of niobium oxide-based matrices doped with Eu 3+ ions obtained by the adapted non-hydrolytic sol-gel route. X-ray diffractograms revealed that increasing the concentration of Gd 3+ ions favored the onset of the Gd 2 O 3 structure decreasing the GdNbO 4 phase. The excitation spectra (λ em  = 613 nm) presented bands corresponding to the 7 F 0  →  5 L J transitions (L = D, G, and L, where J = 0-7), attributed to the Eu 3+ ions, and a broad band at 270 nm, assigned to the charge transfer of the [Formula: see text] group. The emission spectra contained bands refer to the 5 D 0  →  7 F J internal configuration transitions (J = 0, 1, 2, 3, and 4). Finally, the CIE chromaticity coordinates met the standard for the color red established by the National Television Standard Committee (NTSC).

In this work, we report the effects of incorporation of variable amounts (1-20 wt %) of sodium montmorillonite (MMT) into a siloxane-poly(ethylene oxide) hybrid hydrogel prepared by the sol-gel route. The aim was to control the nanostructural features of the nanocomposite, improve the release profile of the sodium diclofenac (SDCF) drug, and optimize the swelling behavior of the hydrophilic matrix. The nanoscopic characteristics of the siloxane-cross-linked poly(ethylene oxide) network, the semicrystallinity of the hybrid, and the intercalated or exfoliated structure of the clay were investigated by X-ray diffraction, small-angle X-ray scattering, and differential scanning calorimetry. The correlation between the nanoscopic features of nanocomposites containing different amounts of MMT and the swelling behavior revealed the key role of exfoliated silicate in controlling the water uptake by means of a flow barrier effect. The release of the drug from the nanocomposite displayed a stepped pattern kinetically controlled by the diffusion of SDCF molecules through the mass transport barrier created by the exfoliated silicate. The sustained SDCF release provided by the hybrid hydrogel nanocomposite could be useful for the prolonged treatment of painful conditions, such as arthritis, sprains and strains, gout, migraine, and pain after surgical procedures.

Context: (-)-6,6'-Dinitrohinokinin (DNHK) display remarkable antiparasitic activity and was, therefore, incorporated into a nanoparticle formulation., Objective: Incorporation of DNHK in poly lactic-co-glycolic acid (PLGA) nanoparticles aiming to improve its biological activities., Materials and Methods: Synthesis, characterization and incorporation of DNHK into glycolic acid (PLGA) nanoparticles by nanoprecipitation method. The nanoparticles were characterized by ultraviolet-visible spectroscopy, X-ray diffraction, field emission electron microscopic scanning mansoni (FESEM), and dynamic light scattering (DLS). For the in vitro test with Schistosoma mansoni, the DNHK-loaded PLGA was diluted into the medium, and added at concentrations 10-200 µM to the culture medium containing one adult worm pair. The parasites were kept for 120 h and monitored every 24 h to evaluate their general condition, including: pairing, alterations in motor activity and mortality., Results: The loaded PLGA nanoparticles gave an encapsulation efficiency of 42.2% and showed spherical characteristics in monodisperse polymeric matrix. The adult worm pairs were separated after 120 h of incubation for concentrations higher than 50 µM of DNHK-loaded PLGA. The groups incubated with 150 and 200 µM of DNHK-loaded PLGA for 24 and 120 h killed 100% of adult worms, afforded LC 50 values of 137.0 ± 2.12 µM and 79.01 ± 1.90 µM, respectively, which was similar to the effect displayed by 10 µM of praziquantel., Discussion and Conclusions: The incorporation of DNHK-loaded showed schistosomicidal activity and allowed its sustained release. The loaded PLGA system can be administered intravenously, as well as it may be internalized by endocytosis by the target organisms.

This work reports the use of a cross-linked ureasil-PEO hybrid matrix (designated PEO800) as an efficient adsorbent to retain the emerging contaminant bisphenol A (BPA) from an aqueous medium. The in-deep experimental and theoretical results provide information about the interactions between PEO800 and BPA. The in situ UV-vis spectroscopy data and the pseudo-first order, pseudo-second order, Elovich, and Morris-Webber intraparticle diffusion models allowed us to propose a three-step mechanism for the adsorption of BPA onto PEO800. The results indicate that the pseudo-first-order kinetic model effectively describes the adsorption of BPA onto PEO800. Differential scanning calorimetry (DSC) and Fourier transform infrared (FTIR) spectroscopy confirmed the interaction of PEO800 with BPA, showing an alteration in the chemical environment of the polymer ether oxygen atoms present in the hybrid matrix. The molecular dynamic simulation provides further evidence that the BPA molecules interact preferentially with PEO. The amount of desorbed BPA depended on the pH and solvent used in the assays. This work provides new opportunities for using the hydrophilic ureasil-PEO matrix which has demonstrated its abilities in being a fast and easy alternative to successfully removing organic contaminants from aqueous mediums and therefore having potential applications in water remediation. Graphical abstract.

Humic acids (HAs) are ubiquitous macromolecules in the environment. Due to their high contents of oxygenated functional groups, they can interact with contaminants present in the natural environment and therefore influence the behavior of pollutants. However, a pH of 2 or lower is required to maintain HAs in the solid form. To increase the stability of HAs and their capacity to bind to contaminants, this work proposes the development of new hybrid materials based on alkoxysilanes and HAs for environmental applications such as dye adsorption. Three different materials with new functional groups were prepared by employing the following alkoxysilanes: tetraethyl orthosilicate, (3-aminopropyl)triethoxysilane, and N-[3-(trimethoxylsilyl)propyl]ethylenediamine. The final materials were denoted HWA, HOA, and HTA, respectively, and they were characterized by elemental analysis, diffuse reflectance Fourier-transform infrared spectroscopy (DRIFT), small-angle X-ray scattering (SAXS), scanning electron microscopy (SEM), and N2 gas-volumetric adsorption. The point of zero charge (pzc) and stability of these materials were also determined. Their selectivity was evaluated in adsorption experiments performed with two different charged dyes in aqueous medium, namely anionic rose bengal (RB) and cationic methylene blue (MB). The elemental, DRIFT, SAXS, SEM, and textural analyses confirmed the presence of a combination of the features of HAs and alkoxysilanes. The pzc results showed that the new materials displayed different characteristics and affinities. All the materials were stable in aqueous solution up to pH 10. For MB, the percentage removal values obtained by using HWA, HOA, and HTA were 98, 85, and 67%, respectively. As for RB, the percentage removal values were 19, 18, and 44% for HWA, HOA, and HTA, respectively. These hybrid materials have potential use as adsorbents for the removal of cationic or anionic species and could be viable alternatives to remove various substances present as contaminants in natural environments.

Herein, we present a cross-linked ureasil-polyether-siloxane hybrid (labeled PEO500) that can function as a stimuli-sensitive material; it swells or shrinks in response to changes in the environmental conditions and it can also, effectively and selectively, remove dyes from water solution. We also developed a methodology to separate a mixture of cationic and anionic dyes present in water. Addition of PEO500 to an aqueous solution of the anionic orange II (OII) or the ponceau S (PS) dye rendered the solution colorless, but an aqueous solution of cationic methylene blue (MB) remained unchanged after 2 h of contact with the insoluble matrix. In situ small-angle X-ray scattering (SAXS) showed that the distance of siloxane nanodomains are strongly affected by the swelling or shriking. By in situ UV-vis adsorption experiments, we found that the kinetics of OII and PS removal followed a pseudo-first-order rate equation. We accomplished B3LYP calculations, to establish which sites on the matrix interacted with the dyes and to investigate the nature of the matrix-dye chemical bonds. On the basis of the experimental and theoretical investigations, we proposed some mechanisms to explain how PEO500 adsorbs anionic dyes efficiently. This "smart" matrix is potentially applicable as an efficient, fast, selective, and convenient device in water treatment and stimuli-sensitive response materials.

Efficient incorporation of (PtCl3EtOH)(-) anion derived from CisPt moiety into ureasil-PPO (poly(propylene oxide)) network was achieved from one-pot sol-gel synthesis carried out in the presence of water, HCl, and ethanol. Reactant proportion was adequately chosen to lead the sol-gel formation of siloxane nodes at the end of short PPO chains, to prevent the CisPt hydrolysis, and to induce platinum ligand exchange. The efficient dissolution of Pt species and the formation of a homogeneous liquid-like solution on the transparent and elastomeric ureasil-PPO hybrid were evidenced by differential scanning calorimetry and small-angle X-ray scattering. The CisPt ligand exchange and the formation of a Zeise-type salt Y(+)(PtCl3R)(-) were demonstrated by Raman spectroscopy and Pt L3-edge EXAFS analysis. In light of these results and in agreement with the proportion of reactants introduced in the media for synthesis and those self-produced by hydrolysis and condensation processes, we proposed for R the ethanol moiety and for Y the ammonium cation. The Raman spectroscopy studies indicated also that the ammonium cations are coordinated by the ether-type oxygen atoms of the PPO chains backbone, whereas the amine groups of the urea linkage participate in the (PtCl3EtOH)(-) anion coordination. In situ Raman monitoring of Pt species decomplexation induced by immersion of hybrid matrix in water highlighted the specific participation of Pt ligands in interaction with the urea group and of NH4(+) cations coordinated by ether-type oxygen atoms in the formation of supramolecular interactions between the PPO chains. The electrospray mass spectrometry analysis of the Pt species released in water from the ureasil-PPO hybrid evidenced that the structure of the complex, NH4 (PtCl3 EtOH), incorporated in the matrix is totally preserved after delivery. Due to both well-known antitumoral and catalytic activities of Pt species, the results reported herein are of prime importance for further applications as drug delivery systems with optimized release pattern or as potential materials for new conceptual development of in situ catalyst delivery in homogeneous catalysis.

Anionic microemulsions (MEs) containing soya phosphatidylcholine, Tween-20, sodium oleate as surfactant, and cholesterol as oil phase were investigated as drug carriers for amphotericin B. Depending on the composition of the microemulsion, various structures, which differently interact with amphotericin B, can be formed. The nanostructured systems were characterized by photon correlation spectroscopy, rheological behavior, and polarized light microscopy. The results reveal that the droplet diameters increased with amphotericin B incorporation for all ranges of surfactant and oil phase. For both amphotericin B-unloaded and amphotericin B-loaded microemulsions, the profile of the oil droplet diameter decreased with increasing the surfactant concentration, demonstrating the stabilizing effect of the surfactant. The increase in the oil phase proportions led to the growth of the droplet diameter, clearly demonstrating the limit of the surfactant organization in the oil-water interface. The amphotericim B incorporation into microemulsion increased with the fraction volume of the oil phase and the surfactant concentration reaching a plateau at high contents. This profile could be quantitatively analyzed by the framework of the pseudo-phase model that considers the amphotericim B distribution between the oil and the aqueous phases. The rheological analysis showed a pseudoplastic behavior with little thixotropic characteristic. Under polarized light, the system of interest showed a dark background characteristic of dispersed droplets. However, for both amphotericim B-loaded and amphotericim B unloaded microemulsions, the increase in the O/S ratio led to the formation of ordered structures with lamellar arrangements.

The ability of assembling inorganic, organic, and even bioactive components in a single material unfolds an exciting direction in the development of novel multifunctional hybrid materials. Recently, we have observed that the hydrophilic/hydrophobic character of the organic polymeric moieties determines the swelling/diffusion control of the drug release. In this work, the antitumor cisplatin (CisPt) molecules incorporated into the ureasil-PEO (poly(ethylene oxide)) hybrid material was used as a probe for the in situ and simultaneous UV-vis and Raman spectroscopies monitoring of the kinetics of both the water uptake as well as the CisPt release by the hybrid matrix. Drug molecules were incorporated during the hydrolysis and polycondensation steps. The monolithic xerogel were analyzed by X-ray absorption spectroscopy and differential scanning calorimetry, while the drug release properties were monitored by Raman as well as UV-vis spectroscopies. The results show that the molecular structure of the CisPt is preserved in the one pot sol-gel route used in synthesizing the CisPt-loaded PEO1900 hybrid. The in situ monitoring of water uptake clearly points out the key contribution of the osmotic flow on the stepped profile of the CisPt delivered from the PEO1900 hybrid matrix.