ACS Omega最新文献

Activated carbon was obtained from polyethylene terephthalate (PET). Three activating agents were tested (KOH, ZnCl₂, and H₃PO₄) while evaluating effluents containing sodium diclofenac, and an investigation into the optimal conditions for effluent treatment was conducted. H₃PO₄ showed a higher adsorption capacity (34.06 mg·g^–1) to sodium diclofenac when used in a 2:1 ratio (mass of H₃PO₄: mass of carbon). MEV analyses show that the materials exhibit mesopores and macropores on the surface of the activated carbon obtained (15.3–120 nm). BET analyses revealed that H₃PO₄ activation produced the largest surface area (542.97 m²·g^–1), corroborating the morphological observations and explaining the superior performance in sodium diclofenac adsorption. Four kinetic and two isotherm adsorption models were also tested to fit the experimental data. The kinetic and isotherm adsorption tests indicated that this capacity can be maximized when the process is carried out at 25 °C for 25 min (estimated adsorption capacity of 200 mg·g^–1). The kinetic and isotherm adsorption models enabled simulations to replicate the batch process and to prospect the industrial application of an adsorption column.

Iron-gall inks (IGI) were among the most widely used writing materials in historical manuscripts. However, their presence is now recognized as a major cause of degradation in many of these documents. Common forms of deterioration include ink fading and discoloration, embrittlement of the writing support, crack formation, and material loss. Understanding the mechanisms underlying IGI-induced degradation is therefore crucial for developing effective strategies for the preservation of historically valuable manuscripts. In this study, a systematic and multi-analytical approach, involving the use of Raman, electron paramagnetic resonance, and infrared spectroscopy, was employed to investigate the degradation processes associated with IGI, with a specific focus on their intrinsic chemical variability. Three key parameters were considered: the structure of the polyphenolic ligand, the pH, and the iron-to-ligand ratio. These variables were selected to evaluate their respective contributions to the observed degradation phenomena. The findings provide a comprehensive overview of the main degradation pathways and the factors influencing them. Among the results, some indicate the occurrence of hydrolytic processes involving the complex ligands, which seem confined to the acidic conditions applied during sample preparation. In addition, the results enabled comparison of the differences in oxidation rates observed during accelerated aging, revealing how these rates vary according to the structure of the complexes. Overall, the study establishes a robust and reproducible framework that lays the groundwork for future research on IGI-related degradation.

American trypanosomiasis is a parasitic illness of major public health relevance, resulting from infection with the protozoan Trypanosoma cruzi and predominantly impacting populations in low-resource settings. Current treatments, benznidazole and nifurtimox, are limited by their efficacy in the chronic phase, toxicity, and side effects, necessitating the search for new therapeutic agents. Cruzain, a key protease for parasite survival and infection, is a validated drug target. This work involved the synthesis and characterization of novel amides derived from 1,2,3,4-tetrahydroisoquinoline-3-carboxylic acid. Their activity was evaluated against both cruzain and T. cruzi. The hydrochloride salts 4a and 4b showed moderate cruzain inhibition (60.2 ± 2.4% and 69.3 ± 2.6% inhibition at 100 μM, respectively). Notably, compound 3d and its hydrochloride salt 4d demonstrated significant antiparasitic activity with IC₅₀ values of 10.5 and 13.7 μM, respectively. However, their low cruzain inhibition (∼15%) suggests that their mechanism of action is likely through a different biological target.

Effective cancer therapy remains challenging due to poor tumor specificity, low drug bioavailability, and systemic toxicity of conventional treatments. Herein, we develop a glutathione (GSH)-responsive nanodrug, PEG-SS-PCL@Fe-DOX, which synergistically combines ferroptosis and chemotherapy to achieve enhanced antitumor efficacy. This nanosystem employs a disulfide-linked amphiphilic polymer (PEG-SS-PCL) to encapsulate the Fe-DOX complex, enabling GSH-triggered, tumor-specific drug release. In the tumor microenvironment, cleavage of disulfide bonds facilitates the release of DOX and Fe²⁺, where DOX intercalates into DNA to inhibit proliferation, and Fe²⁺ catalyzes Fenton reactions and suppresses GPX4 activity, collectively inducing excessive reactive oxygen species production and ferroptosis. This synergistic mechanism markedly improves therapeutic efficiency, offering a promising strategy for precise and effective cancer treatment.

Bioaerosols are microorganisms in the air, such as bacteria, viruses, fungi, or allergens. Their concentration and health risks are increasing due to the current pandemic and rising pollution in cities. They are hard to control and eliminate because of their diversity, fluctuating concentrations, and changing environments they inhabit. Recent progress in materials science, nanotechnology, and sensor engineering has led to the development of more advanced, faster, and more reliable bioaerosol detection systems. This review covers current trends in bioaerosol capture and detection, focusing on multifunctional porous materials and real-time analysis. For example, materials engineered with metals, pores, or active surfaces can trap airborne microbes and neutralize them through photocatalytic or oxidative reactions, including metal–organic frameworks (MOFs), covalent organic frameworks (COFs), and carbon-based nanostructures. Highly efficient, self-disinfecting filtration membranes treated with antimicrobials like silver nanoparticles, TiO₂, and enzymes are also in use. Detection technology is similarly transformative. Optical methods such as dynamic light scattering (DLS), multiwavelength fluorescence spectroscopy (MFS), and hyperspectral imaging (HSI) enable real-time, noninvasive monitoring of microbes. Likewise, electrochemical biosensors enhanced with aptamers, antibodies, and nanomaterials offer increased sensitivity, portability for on-site testing, and the ability to detect very low pathogen levels. Access to personalized environmental health monitoring is now feasible through integrated platforms in wearable and smart infrastructure. Despite these advancements, challenges such as environmental variability, false positives, and sensor lifespan remain. This review discusses how these issues arise and explores future trends in biosensor design, data integration, and standardization.

Candida glabrata is the second leading cause of mortality in immunocompromised patients hospitalized for invasive candidiasis (IC). Several drugs have been available to treat this disease for decades, such as polyenes, azoles, echinocandins, flucytosine, and, in critical cases, amphotericin B. However, these antifungals’ constant and routine use have led to the development of resistance mechanisms, making the design and development of new drugs indispensable. The first step for the design and subsequent synthesis of a new chemical molecule as a potential antifungal is the identification of new therapeutic targets. In that pathway, our working group has identified moonlight-like cell wall proteins (CWPs) in different Candida species that can act as potential antifungal targets. One of these moonlight-like CWPs is phosphoglycerate kinase (Pgk) from C. glabrata. Once Pgk was identified as a potential therapeutic target in different human pathogens, the first step to perform drug design against this moonlight-like CWP was the elucidation of the three-dimensional (3D) structure since the 3D structure is key to understanding the interactions between a drug candidate and its target at the molecular level. In the present work, we aimed to elucidate the 3D structure of C. glabrata Pgk. To elucidate the 3D structure of this protein, the recombinant protein was expressed, purified, and structurally resolved by means of a structural analysis by small-angle X-ray scattering (SAXS). Additionally, in order to evaluate its potential as a therapeutic target, we have performed molecular docking studies and enzymatic activity assays with pure Pgk using known antifungals amphotericin B, nystatin, and fluconazole and with the new plausible drugs, such as nilotinib and netupitant. Our results showed some similarities and differences with orthologous Pgk proteins from other organisms, which was expected since Pgk has been observed to have evolved in the kingdoms of life. Molecular docking studies showed that Pgk interacts with all of the compounds tested. In enzyme activity assays, a change in the kinetic parameter Km on the enzyme Pgk was observed in response to its interaction with nilotinib, netupitant, and amphotericin B. Thus, our results allow us to propose Pgk from C. glabrata as a possible therapeutic target against candidiasis. We consider it essential to design and develop new molecules specifically targeting this enzyme, which will contribute to a decrease in mortality associated with IC and improve the patient’s quality of life.

Efficient and sustainable pretreatment of lignocellulosic biomass is critical for biofuel and biochemical production, yet its optimization is often hindered by slow, labor-intensive experimental methods. Here, we report the first demonstration of a custom-built, miniaturized, high-throughput screening platform integrated with one-pot enzymatic saccharification, enabling parallel evaluation of solvent type, feedstock, and temperature with minimal material use and high reproducibility. As a proof-of-concept, the HTX platform was used to screen five amine-functionalized solvents, including isopropanolamine, butylamine, N-methylbutylamine, ethanolamine, and ethanolamine acetate across three bioenergy crops (sorghum, poplar, and switchgrass) and pretreatment temperatures ranging from 80 to 140 °C. Vacuum drying successfully removed more than 99% of the solvents from the pretreated biomass, eliminating the need for water washing prior to saccharification. Isopropanolamine and N-methylbutylamine yielded the highest glucose (70–80%) and xylose (58–67%) release, with trends reflecting feedstock recalcitrance. The produced hydrolysates supported robust growth of an engineered strain of the yeast Rhodosporidium toruloides, confirming biocompatibility. This high-throughput platform provides a scalable, feedstock-agnostic framework for rapid pretreatment screening, accelerating solvent–feedstock pairing and process optimization. Its ability to integrate pretreatment, solvent removal, saccharification, and microbial conversion in a miniaturized format offers significant advantages for cost-competitive biorefinery development.

The study aimed to produce spray-dried microparticles with a higher payload of rifampicin and a suitable size range for targeted drug delivery to alveolar macrophages. The microparticles were initially optimized with respect to solution feed rate, concentration of chitosan, and addition of surfactant, followed by homogenization. The optimized formulations were loaded with rifampicin in the ratios of 1:1 (F4L), 1:2 (F3L and F5L), and 1:4 (F2L), respectively. The microparticles were assessed for their particle size, morphology, drug content, flow properties, drug release, and aerodynamic performance. The chemical compatibility of the drug with excipients in microparticles was assessed using FTIR, while the crystalline and/or amorphous nature of the spray-dried powder was confirmed using XRD analysis. The pharmacokinetic parameters were compared after oral and intratracheal administration in rats. The microparticles, within the size range of 2 to 6 μm and percentage yield of 23–51%, were efficiently synthesized. The structure of the microparticles was significantly altered with increasing concentrations of rifampicin in the microparticles. The microparticles had a drug association efficiency of above 60%. The microparticles released rifampicin in a sustained fashion (>95%) by anomalous non-Fickian diffusion. The optimized microparticles (F5L) achieved a dispersed fraction of 89%, an inhaled fraction of 69% with FPF_≤3 μm of 51.51%. The microparticles achieved a significantly lower area under the curve (AUC) of 80.845 ± 9.42 μg/mL·h than marketed tablets (140.468 ± 12.53 μg/mL·h) due to higher lung drug retention. The in vitro and in vivo findings indicate the suitability of microparticles for potential applications in tuberculosis.

Specific vibration energy harvesting applications require high deformability to harvest mechanical energy efficiently. Polymer-piezoelectric particle composites have been attractive as they inherently possess high flexibility. However, this flexibility can be further enhanced by increasing porosity. In this work, three types of flexible composite structures, dense sheet, porous film, and fiber mat, which were composed of polyvinylidene fluoride (PVDF) matrix and (Ba,Ca)(Zr,TI)O₃ (BCZT) ceramic particles, were produced. To evaluate the mechanical properties of these composites, the focus was on measurements of the dynamic stress–strain hysteresis loop. By analyzing the hysteresis loop, it was found that the storage modulus G′ reduced by 77% for the porous thick film compared to the dense sheet, and the mechanical loss (tan ∂) was 0.51 for both the sheet and the thick film at the tensile strain rate of 2.0 mm/s (=2.5 Hz). Mechanical energy dissipated per cycle at 2 mm/s was 67.6 kJ/m³ for the sheet, 15.8 kJ/m³ for the thick film, and 0.127 kJ/m³ for the fiber mat. This study highlights the understanding that microstructure control, including pores and fibers, modulates dynamic stress patterns.

Due to its charge-transfer capabilities and tunable band structure, graphitic carbon nitride (g-C₃N₄) stands out as a promising photocatalyst. However, its efficiency is limited by low visible-light absorption and the rapid recombination of electron–hole pairs. This computational study uses density functional theory (DFT) to investigate the influence of BH and NH substitution on g-C₃N₄ building blocks, which can be combined to promote charge transfer and visible-light absorption. The introduction of boron (BH substitution) creates an electron-deficient region and enhances charge transfer, thereby improving the photocatalytic efficiency, while hydrogen (NH substitution) adjusts the excitation energy levels, shifting them into the visible spectrum and placing them in the correct energetic alignment with respect to the standard hydrogen electrode (SHE) and oxygen evolution reaction (OER) potentials. The results demonstrate the interesting potential of combining different substitution strategies within a single photocatalyst model without compromising the individual physical properties of each substitution type, thereby enhancing light absorption and reducing the electron–hole recombination rate.