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The Zika virus (ZIKV) is a global health threat due to its rapid spread and severe health implications, including congenital abnormalities and neurological complications. Differentiating ZIKV from other arboviruses such as dengue virus (DENV) is crucial for effective diagnosis and treatment. This study presents the development of a biosensor for detecting the ZIKV non‐structural protein 1 (NS1) using gold nanoparticles (AuNPs) functionalized with monoclonal antibodies employing dynamic light scattering (DLS). The biosensor named ZINS1‐mAb‐AuNP exhibited specific binding to the ZIKV NS1 protein, demonstrating high colloidal stability indicated by a hydrodynamic diameter (DH) of 140 nm, detectable via DLS. In the absence of the protein, the high ionic strength medium caused particle aggregation. This detection method showed good sensitivity and specificity, with a limit of detection (LOD) of 0.96 μg mL−1, and avoided cross‐reactivity with DENV2 NS1 and SARS‐CoV‐2 spike proteins. The ZINS1‐mAb‐AuNP biosensor represents a promising tool for the early and accurate detection of ZIKV, facilitating diagnostic and treatment capabilities for arboviral infections. [ABSTRACT FROM AUTHOR]

The combination of mesoporous silica nanoparticles (MSNs) with a second material to produce nanocarriers is a strategy to enhance their functionalities. Hydroxyapatite (HAP) is a judicious choice due to its high biocompatibility and osteoconductive and noninflammatory behavior. Herein, we explored the independent advantages of MSNs and HAP by incorporating HAP nanocrystals in the MSNs using different approaches. We demonstrated that by adjusting the synthesis conditions, we modulated, at the nanoscale level, how HAP was integrated into mesoporous silica, either as separated phases (MSN-HAP) or as combined phases in one structure (HAP@MSN). The materials MSN-HAP and HAP@MSN were loaded with doxorubicin (DOX), as a drug model, and were compared with MSNs regarding their physicochemical characteristics, DOX release kinetics, cytotoxicities toward esophagus 2D and 3D (spheroids) cancer cells, and in vivo biochemical effects. The produced DOX-loaded nanocarriers showed tuned properties; e.g., not only did HAP retard the DOX release in comparison with pure MSNs, but also the way the HAP was integrated dictated the kinetics of DOX release. The cytotoxicity studies showed that the presence of HAP prolonged the DOX effect. The biochemical analysis of MSN-HAP-DOX and HAP@MSN-DOX indicated a transient alteration in the liver metabolism, whereas HAP@MSN-DOX had a modest effect on mouse fat metabolism. Therefore, benefiting from the bone-regeneration feature of HAP and the controlled drug release, we envision that MSN-HAP and HAP@MSN are promising materials for clinical translation as long-acting release formulations, especially for bone cancer treatment. [ABSTRACT FROM AUTHOR]

HKUST-1 is a well-known copper-based metal-organic framework (MOF), promising to be used in separation processes, however its industrial usage remains confined due to its difficult handling and low mechanical stability when in powder form. In this work, we have synthesized and analyzed the mechanical properties of novel HKUST-1 shaped composites based on methylcellulose (MC) and poly(vinyl formal) (PVMF), using a simple and inexpensive extrusion technique. The composites were characterized using different techniques, such as Fourier transform infrared (FTIR) spectroscopy and powder X-ray diffraction (PXRD) analysis, which demonstrated that their structure and crystallinity were not compromised by the shaping process. Their mechanical properties were investigated by compressive strength measurements and scanning electron microscopy (SEM). The composite with methyl cellulose showed good mechanical resistance, with an average crushing strength value of 40 N. Nitrogen sorption measurements showed that the specific surface area reduction due to the shaping process for HKUST@MC was only 8.6%. The greater hydrolytic stability after heat activation of HKUST@MC compared to that of the pure MOF was also verified. The adsorptive capacity of HKUST@MC towards organosulfur compounds found in sour gas was evaluated in a desulfurization test using a realistic multicomponent gas mixture. HKUST@MC exhibiting a high efficiency to adsorb organosulfur outperformed the benchmark sulfur adsorbent Norit RGM 3 in the adsorption of ethanethiol and dimethyl disulfide. Therefore, in this work we present a technically feasible and cost-effective method to produce a novel HKUST-1 shaped composite with good mechanical and water resistance properties preserving the MOF porosity and gas adsorption properties. [ABSTRACT FROM AUTHOR]

Producing solar fuels through semiconductor‐based photocatalytic water splitting is one of the main options for worldwide employment of non‐fossil energy sources. Nonetheless, the relatively low efficiency of the known photocatalysts, the high prices of composing elements, and the costly preparation methods render expensive devices that would not be economically competitive with fossil energy sources. Herein, we present a facile method for the preparation of both round hematite (Fe2O3) nanoparticles, with average diameter of (56±7) nm, and of niobium‐doped hematite nanoparticles with similar size and morphology. Thin films of these nanoparticles were assembled through electrophoretic deposition, resulting in homogeneous photoanodes with nanometer thickness that can split water, under simulated solar irradiation, to produce oxygen in a photoelectrochemical cell. The optimization of the film composition and thickness resulted in the improvement of the photocurrent from 352.3 to 1,342.5 μA cm−2 at 1.23 V vs RHE for the pristine hematite and Nb‐doped hematite, respectively, both with thickness of (499±63) nm. This enhancement in the oxidation reaction yield is a clear consequence of the improvement of charge carriers transport along the nanoparticle structure due to niobium doping and adequate light absorption/charge transfer balance of the photoelectrode under operation. [ABSTRACT FROM AUTHOR]

In this work, cationic switchable pillar[5]-arene nanogates that bear an imidazolium scaffold (MIP5+) were constructed, and these nanogates were used to electrostatically interact with negatively charged spherical mesoporous silica nanoparticles (96.0 ± 1.0 nm) and rod-shaped silica particles (391.0 ± 0.2 nm in length and 219 in width), which are both functionalized with carboxypropyl groups. The nanochannels of silica-based materials were used as containers to store the anticancer drug doxorubicin (DXR) trapped by the nanogate. Under physiological conditions (pH = 7.4), DXR molecules were firmly trapped in the nanochannels of the spherical and rod-shaped containers without any premature release, demonstrating that the nanogate was efficient in sealing the nanopores. Under acidic conditions (pH = 4.5), the carboxypropyl groups were protonated, and the electrostatic interactions between the containers and the nanogates were disrupted, releasing the drug. In vitro studies were performed to explore the differences between N-methylimidazolium-pillar-[5]-arene nanogate mounted on DXR-loaded spherical and rod-shaped containers and the resulting cytotoxicity effect against human breast adenocarcinoma cells and cellular uptake. A higher cytotoxicity effect and better cellular uptake were detected for the nanogate on DXR-loaded rod-shaped silica containers. Additionally, this device presents a lower uptake rate by nontumor cells than that of free DXR. Therefore, our findings indicate that the rod shape of mesoporous silica in nanogated devices is important due to the cytotoxicity effect and cellular uptake and should be further explored in drug delivery systems. [ABSTRACT FROM AUTHOR]

Herein a 1D Co(II) coordination polymer of formula [Co(η1-L1)(η2-L1)(py)2(H2O)]n (CoCP) has been synthesised using the rigid H2L1 proligand, containing a long spacer bearing two triple bonds. Single-crystal X-ray diffraction showed that Co(II) adopts a distorted octahedral geometry. The state-averaged complete active self-consistent field (SA-CASSCF) calculation showed that the ground state of CoCP is a high spin quartet with a highly multiconfigurational character of its electronic structure. Due to the large intra- and intermolecular distances between the spin carriers, the magnetic interactions are negligible and the zero-field splitting (ZFS) effects of cobalt(II) ions are predominant. This behavior was confirmed by direct current (DC) magnetic measurements and theoretical calculations using the broken-symmetry approach. Quantum chemical calculations indicate that CoCP has a negative axial component possessing mixed tri-axial anisotropy. The DC magnetic susceptibility data were fitted with a Griffith–Figgis Hamiltonian and the obtained parameters are in good agreement with those simulated by the ab initio calculation. Alternating current (AC) magnetic measurements showed a field induced slow magnetic relaxation in CoCP, which is attributed to the hyperfine interaction effects. [ABSTRACT FROM AUTHOR]

In this work, we report the synthesis and structural characterisation of the ligand 2-(pyridin-3-yl)-benzo[de]isoquinoline-1,3(2H)-dione, 5, its isostructural Werner complexes ML4(NCS)2 (L = 5; M = Co(II) and Ni(II)), and five clathrates with three aromatic guests, ML4(NCS)2·2G (M = Co(II) and Ni(II), G = nitrobenzene (NB); M = Co, G = 1,2-dichlorobenzene (1,2-DCB); M = Co(II) and Ni(II), G = o-xylene (OX)). 5 was prepared in high yield by condensation in the solid-state (C3S3, Cocrystal Controlled Solid-State Synthesis). The Werner complexes ML4(NCS)2 (M = Co(II) and Ni(II)) (apohosts) were prepared by reacting M(NCS)2 (M = Co(II) and Ni(II)) and 5 in 1-butanol at 60 °C for 24 h. The Werner clathrates were prepared by reacting M(NCS)2 (M = Co(II) and Ni(II)), G and 5 in 1-butanol at 60 °C for 48–96 h. The clathrates were observed to transform to the apohost ML4(NCS)2 upon heating. CoL4(NCS)2·2NB was subsequently regenerated by exposing CoL4(NCS)2 to liquid NB at 60 °C for 48 h. This phase change occurred as a single-crystal to single-crystal phase transformation and was studied by single crystal X-ray diffraction, powder X-ray diffraction and thermal analyses. Structural analyses of the apohost CoL4(NCS)2 and its Werner clathrate CoL4(NCS)2·2NB indicated that rotational freedom of the Co-N bonds together with torsional flexibility of the ligand between the imide bond and the pyridine moiety are key to enabling the structural switching induced by exposure to NB or its removal. [ABSTRACT FROM AUTHOR]

A thermally stable carbocationic covalent organic network (CON), named RIO‐70 was prepared from pararosaniline hydrochloride, an inexpensive dye, and triformylphloroglucinol in solvothermal conditions. This nanoporous organic material has shown a specific surface area of 990 m2 g−1 and pore size of 10.3 Å. The material has CO2 uptake of 2.14 mmol g−1 (0.5 bar), 2.7 mmol g−1 (1 bar), and 6.8 mmol g−1 (20 bar), the latter corresponding to 3 CO2 molecules adsorbed per pore per sheet. It is shown to be a semiconductor, with electrical conductivity (σ) of 3.17×10−7 S cm−1, which increases to 5.26×10−4 S cm−1 upon exposure to I2 vapor. DFT calculations using periodic conditions support the findings. [ABSTRACT FROM AUTHOR]

The Cu(II) heptanuclear complex (Cu7atac) was synthesised using the hydrated amino acid ligand 2-(5-amino-1H-1,2,4-triazol-3-yl)acetic acid (Hatac·H2O). Single crystal X-ray diffraction analysis revealed a μ3-hydroxo bridged Cu(II) heptanuclear complex, consisting of two triangular subunits and one Cu(II) ion as a bridge with the formula [Cu7(atac)6(μ3-OH)2(NO3)2(H2O)10](NO3)4. The magnetic behaviour of this discrete 0D complex shows strong antiferromagnetic couplings between Cu(II) mediated by N,N bonding and an anti–anti modes of the carboxylate anion of the ligand atac−. The magnetic data were fitted considering a 3J model. To support the model used to fit the magnetic data of the Cu7atac complex, theoretical calculation methods (complete active space self-consistent field, CASSCF, density functional theory (DFT) using the UKS TPSS/Def2-TZVP//Def2-SVP level and periodic boundary conditions (PBC) using PBE/DZVP-MOLOPT-GTH) were performed to obtain the spin states, spin density map and J couplings. The theoretical results suggest that Cu7atac is a spin-frustrated complex in the ground state, in which the doublet spin state co-exists with the quartet spin state. [ABSTRACT FROM AUTHOR]

Here we describe the assembly and pH-driven operation of two nanocarriers based on non-functionalized (MCM-41) and carboxylate-functionalized (MCM-41-COOH) containers loaded with the anticancer drug doxorubicin (DOX) and capped by quaternary ammonium pillar[5]arene (P[5]A) nanogates. MCM-41 and MCM-41-COOH containers were synthesized and transmission and scanning electron microscopies showed nanoparticles with spherical morphology and dimensions of 85 ± 13 nm. The nanochannels of MCM-41 loaded with DOX were gated through the electrostatic interactions between P[5]A and the silanolate groups formed at the silica–water interface, yielding the MCM-41-DOX-P[5]A nanocarrier. The second nanocarrier was gated through the electrostatic interactions between the carboxylate groups mounted on the surface of MCM-41 and P[5]A, resulting in the MCM-41-COO-DOX-P[5]A nanocarrier. The DOX release profiles from both nanocarriers were investigated by UV-vis spectroscopy at different pH values (2.0, 5.5 and 7.4) and also in the presence of ions, such as citrate3− (19 mmol L−1) and Zn2+ (1.2 and 50 mmol L−1) at 37 °C. MCM-41-COO-DOX-P[5]A can be turned on and off eight times through the formation and breaking of electrostatic interactions. In vitro studies show that MCM-41-COO-DOX-P[5]A can penetrate and release DOX in the nucleus of human breast adenocarcinoma MCF-7 cancer cells leading to a pronounced cytotoxic effect. Therefore, the fabricated nanocarrier based on a water-soluble cationic pillar[5]arene nanogate, which is reversibly opened and closed by electrostatic interactions, can be considered as a promising drug transport and delivery technique for future cancer therapy. [ABSTRACT FROM AUTHOR]

An alternating magnetic field (AMF)-responsive controlled release system has been developed by the binding of mono-6-deoxy-6-(p-tolylsulfonyl)-β-cyclodextrin (βCD-Ts) onto amine-modified superparamagnetic iron oxide nanoparticles (MNP-NH2), resulting in a MNP-βCD nanocarrier. The structural, chemical and colloidal properties of the nanocarrier MNP-βCD were fully evaluated by several techniques. Doxorubicin hydrochloride (DOX), as a model anticancer drug, was loaded onto MNP-βCD resulting in MNP-βCD-DOX and the release process was investigated by varying the temperature (37 and 45 °C), pH (7.4 and 5.0) and presence of an AMF (with and without). DOX can interact with the negatively charged surface of MNP-βCD and also with the cavity of βCD forming inclusion complexes. Under acidic conditions, both the negatively charged surface of MNP-βCD and the ionizable groups of DOX are protonated and the interactions between DOX and the nanocarrier MNP-βCD are weakened, thus, accelerating drug release. Temperature increase can reduce the supramolecular interactions between DOX and the nanocarrier MNP-βCD, favoring DOX release. Thermo-induced burst release at 45 °C has been investigated either by applying an alternating magnetic field (AMF, f = 307 kHz) or heating the solution in a thermostatic cuvette holder. In the absence of an AMF at 45 °C and at the pH value of the lysosome (5.0), 92% of DOX was released into the solution within 6 h. Importantly, in an AMF, at 45 (±1) °C and pH = 5.0, the same percentage of DOX release was observed after 50 min. Furthermore, in vitro assays revealed that the unloaded MNP-βCD nanoparticles (100 μg mL−1) displayed negligible cytotoxicity against A549 human lung adenocarcinoma cells either in the absence or presence of an AMF (H×f = 4.9 × 109 A m−1 s−1) applied for 30 min on the cells. In the presence of an AMF no macroscopic temperature variation was detected in the wells containing the cells incubated with DOX unloaded MNP-βCD nanoparticles. The same amount of DOX loaded nanoparticles (MNP-βCD-DOX) showed cytotoxicity only in the presence of an AMF (H×f = 4.9 × 109 A m−1 s−1 applied for 30 min), inducing cell death. Also, no macroscopic temperature variation was detected; therefore, DOX release might be associated with local heating generated from the rotation movements of the nanoparticles (Brown relaxation) upon AMF application. Thus, the DOX loaded β-cyclodextrin-decorated superparamagnetic nanoparticles (MNP-βCD-DOX) are a potential controlled drug release agent with cancer-killing properties under an AMF. [ABSTRACT FROM AUTHOR]

Two series of flexible dicyanomethylene compounds, specifically, class 1 and class 2 compounds, have been designed and synthesised. In class 1 compounds, the dicyanomethylene groups are separated by glycol chain spacers of different lengths, whereas, in class 2 compounds, the spacers are alkyl linkers of different lengths. The notion underlying the design of these compounds is that in class 1 molecules, the spacers contain donor oxygen atoms that could not only form hydrogen bonds during the course of crystal packing but also promote withdrawing effects that modify the photophysical and electrochemical properties of these molecules in solution; in contrast, these effects would be absent for class 2 molecules. However, this study revealed that, with respect to crystal packing, the size of the spacers and their even and odd numbers of atoms are more important than their chemical nature. All of the synthesised compounds exhibited blue emission in the solid state and in CH2Cl2 solutions. The photophysical and electrochemical properties of these compounds in solution were not significantly affected by the type and length of the spacer that was used in each molecule. In the solid state, however, the compound with the shortest spacer showed the highest Stokes shift. The electronic transitions for the synthesized compounds in solution were explained by density functional theory and time-dependent density functional theory calculations, which indicated that the methylene moieties control the properties of both classes of compounds and that the spacers do not conjugate with the end groups. These two series of flexible dicyanomethylene compounds could be utilised as molecular building blocks for the development of new solids with novel properties. [ABSTRACT FROM AUTHOR]

Inspired by the concept of multivalency in living systems, two mechanically interlocked molecules have been conceived that incorporate not once or twice but thrice the features of a pH-switchable [2]rotaxane with two orthogonal recognition sites for dibenzo[24]crown-8 (DB24C8), and 2,3-dinaphtho[24]crown-8 (DN24C8)-one a dialkylammonium ion (CH2NH2+CH2) and the other a bipyridinium dication (BlPY²+). Whereas at low pH, the CH2NH2+CH2 sites bind the DB24C8/DN24C8 macrocycles preferentially, at high pH, deprotonation occurs with loss of hydrogen bonding and the macrocycles will move to the BIPY²+ sites, where they can acquire some stabilizing [π-π] stacking interactions. Such mechanically interlocked molecules have been assembled from a trifurcated rig-like component wherein the dumbbell-like components of three [2]rotaxanes have one of their ends fused onto alternate positions (1,3,5) around a benzenoid core. The rig is mechanically interlocked by a platform based on a tritopic receptor, wherein either three benzo[24]crown-8 or three 2,3-naphtho[24]crown-8 macrocycles are fused onto a hexaoxatriphenylene core. The synthesis of these molecular elevators involves 1:1 complexation, followed by stoppering, i.e., feet are added to the rig. ¹H NMR spectroscopy and cyclic voltammetry, aided and abetted by absorption spectroscopy, have been employed to unravel the details of the mechanism by which the rig and platform components move on the alternate addition of base and acid. For each molecular elevator, the platform operates by taking three distinct steps associated with each of the three deprotonation/reprotonation processes. Thus, molecular elevators are more reminiscent of a legged animal than they are of passengers on freight elevators. [ABSTRACT FROM AUTHOR]

Emerging contaminants, such as the hormone 17α‐ethynylestradiol (EE), in aquatic environments pose a serious risk to both human and environmental health, making efficient removal essential. This study evaluated the effectiveness of three‐dimensional porous carbon structures derived from poly(acrylic acid) (PAAc, Carbopol 990) as adsorbents for removing EE from aqueous solutions. Activated carbon materials were prepared using varying ratios of KOH as an activating agent (PAAc : KOH; 1 : 0 AAC, 1 : 1 AC1, 1 : 2 AC2, and 1 : 3 AC3). Adsorption tests were conducted by adding 10 mg of the adsorbent to 40 mL of an EE solution (100 ppm, 20 % acetonitrile in water). Analyses including TGA, XRD, and Raman spectroscopy were performed to evaluate the materials’ structural properties and adsorption capacities. Among the materials, AC3 exhibited the highest adsorption capacity for EE (238 mg g−1), followed by AC2 (153 mg g−1) and AC1 (82 mg g−1). The superior efficiency of AC3 can be attributed to its larger surface area and pore volume, enabling greater interaction with EE molecules. These materials demonstrated higher adsorption capacities compared to commercial activated carbons and single‐walled carbon nanotubes. This work opens new possibilities for developing efficient adsorbents, contributing to more effective and sustainable solutions for water purification and environmental protection. [ABSTRACT FROM AUTHOR]

Biochar-based catalysts and waste polystyrene were employed to study their effects on both the yield and composition of the oil produced on the intermediate pyrolysis of green coconut (Cocos nucifera L.) pericarp through catalytic co-pyrolysis. Biochar from intermediate pyrolysis was directly employed as a catalyst, but steam-activated biochars with different activation times from single step activation were also studied as low-cost catalysts. The properties of the catalysts were characterized by N 2 physisorption, SEM, SEM-EDS, XRD, and ATR-FTIR techniques. From these techniques, AAEM (especially K) and O-containing functional groups were identified on both biochar and activated biochars, but the activated ones presented a higher surface area (>600 m2 g−1). Results from pyrolysis assays confirmed that co-processing biomass and waste plastic leads to a higher yield of oil while greatly shifting the product composition towards less oxygenated compounds. Catalytic co-pyrolysis with low-cost catalysts confirmed that it is possible to attain a high yield of monoaromatics without relying on zeolite catalysts. This effect was attributed to a synergetic effect between waste polystyrene and activated biochar, which ultimately resulted in an oil organic fraction containing up to 60% of xylene in its composition and presenting a HHV of 34.11 MJ kg−1. [Display omitted] • Intermediate pyrolysis of coconut pericarp was studied. • Co-processing with waste polystyrene improved bio-oil yield. • Biochar-based materials were studied as low-cost catalysts. • Biochar and activated biochar catalysts improved both heating value and composition of bio-oil organic fraction. • Toluene and xylene were major compounds found on bio-oil organic fraction. [ABSTRACT FROM AUTHOR]

Here we report a new synergic strategy for the synthesis of metal-organic frameworks (MOFs), the sonoelectrochemical method. The metal-organic framework HKUST-1 [Cu 3 (BTC) 2 (H 2 O) 3 ] n was successfully prepared by using this approach. Structural and morphological properties of HKUST-1 were studied and results compared with those obtained for the same material synthesized via a conventional solvothermal method. The sonoelectrochemical approach allowed the preparation of powder samples with nanosized characteristics, high yields and in a short time. Furthermore, we confirmed that this route worked well for the synthesis of others MOFs, such as ZIF-8 and MIL-53. Such simple and practical strategy may allow the large-scale production of MOFs, which is of great interest for industrial applications. [ABSTRACT FROM AUTHOR]

Leishmaniasis, a critical Neglected Tropical Disease caused by Leishmania protozoa, represents a significant global health risk, particularly in resource-limited regions. Conventional treatments are effective but suffer from serious limitations, such as toxicity, prolonged treatment courses, and rising drug resistance. Herein, we highlight the potential of inorganic nanomaterials as an innovative approach to enhance Leishmaniasis therapy, aligning with the One Health concept by considering these treatments' environmental, veterinary, and public health impacts. By leveraging the adjustable properties of these nanomaterials─including size, shape, and surface charge, tailored treatments for various diseases can be developed that are less harmful to the environment and nontarget species. We review recent advances in metal-, oxide-, and carbon-based nanomaterials for combating Leishmaniasis, examining their mechanisms of action and their dual use as standalone treatments or drug delivery systems. Our analysis highlights a promising yet underexplored frontier in employing these materials for more holistic and effective disease management.

The data provided in this study are related to the fabrication of two light-responsive systems based on reduced graphene oxide (rGO) functionalized with the polymers Pluronic P123 (P123), rGO-P123, and polyethyleneimine (PEI), rGO-PEI, and loaded with amphotericin B (AmB), an antileishmanial drug. Here are described the experimental design to obtain the systems and characterization methods, such as Attenuated Total Reflectance-Fourier Transform Infrared Spectroscopy (ATR-FTIR), Raman Spectroscopy, Powder X-Ray Diffraction, Transmission Electron Microscopy, Scanning Electron Microscopy and Thermogravimetric Analyses. Also, AmB spectroscopy studies are described. The materials rGO-P123 and rGO-PEI were loaded with AmB and the optimization of AmB and polymer fragments structures revealed several possible hydrogen bonds formed between the materials and the drug. The drug release was analyzed with and without Near-Infrared (NIR) light. In the studies conducted under NIR light irradiation for 10 min, an infrared lamp was disposed at 64 cm from the samples and an optical fiber thermometer was employed to measure the temperature variation. Cytotoxicity studies and antiproliferative assays against Leishmania amazonensis promastigotes were evaluated. The complete work data entitled Amphotericin-B-Loaded Polymer-Functionalized Reduced Graphene Oxides for Leishmania amazonensis Chemo-Photothermal Therapy have been published to Colloids and Surfaces B: Bionterfaces (https://doi.org/10.1016/j.colsurfb.2021.112169) [1]., Competing Interests: 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., (© 2022 The Author(s). Published by Elsevier Inc.)

Polyaniline-decorated ZIF-8 nanoparticles (nPANI@nZIF-8) were easily synthesized and employed as a multifunctional system for the delivery of the antitumor drug 5-fluorouracil (5-FU). Because of the storage ability of the network ZIF-8, 68% of the total amount of the 5-FU drug was released at pH 5.2. The system exhibits absorption in the near-infrared (NIR) region and can be used in the photothermal therapy owing to the presence of nPANI, which has a strong NIR uptake. This absorption causes local hyperthermia by aiding in the diffusion of the drug molecules contained by the polymer into nPANI@nZIF-8/5-FU achieving a greater release of the 5-FU drug, about 80% activated by an NIR laser (λ = 980 nm). This hyperthermia reached about 70 °C (200 μL, 1 mg mL -1 nPANI@nZIF-8), which was directly proportional to the concentration of the material. Therefore, our work can aid in the construction of new chemo-photothermal platforms that may be employed in cancer therapy., Competing Interests: The authors declare no competing financial interest.

Background: A deeper knowledge on the effects of the degradation of magnetic nanoparticles on their magnetic properties is required to develop tools for the identification and quantification of magnetic nanoparticles in biological media by magnetic means., Methods: Citric acid and phosphonoacetic acid-coated magnetic nanoparticles have been degraded in a medium that mimics lysosomal conditions. Magnetic measurements and transmission electron microscopy have been used to follow up the degradation process., Results: Particle size is reduced significantly in 24 h at pH 4.5 and body temperature. These transformations affect the magnetic properties of the compounds. A reduction of the interparticle interactions is observed just 4 h after the beginning of the degradation process. A strong paramagnetic contribution coming from the degradation products appears with time., Conclusions: A model for the in vivo degradation of magnetic nanoparticles has been followed to gain insight on the changes of the magnetic properties of iron oxides during their degradation. The degradation kinetics is affected by the particle coating, in our case being the phosphonoacetic acid-coated particles degraded faster than the citric acid-coated ones.

Two dendrimers were designed and synthesized that contain a 1,3,5-trisubstituted benzenoid core and incorporate 9 and 21 viologen (4,4'-bipyridinium) units in their branches in addition to hydrophilic (aryloxy) terminal groups. For comparison purposes, model compounds containing one and two viologen units were also studied. These polycationic dendrimers form strong host-guest complexes with the dianionic form of the red dye eosin in dilute CH(2)Cl(2) solutions. Titration experiments, based on fluorescence measurements, showed that each viologen unit in the dendritic structures becomes associated with an eosin dianion. Electrochemical (in MeCN) and photosensitization (in CH(2)Cl(2)) experiments revealed that only a fraction of the viologen units present in the dendritic structures can be reduced. This fraction corresponds to the number of viologen units present in the outer shells of the dendrimers. The reasons for incomplete charge pooling are discussed. Comparison with the behavior of polyviologen dendrimers that are terminated with bulky tetraarylmethane groups and were studied previously enabled the role played by the terminal groups in the redox and hosting properties to be elucidated.