RSC Advances最新文献

The cadmium ion (Cd²⁺) is highly poisonous and nondegradable and easily bioaccumulates through the food chain. Therefore, it is crucial to develop cost-effective chemical sensors for Cd²⁺ with fast response time, high selectivity, and very low detection limits. In this study, a colorimetric sensor for the determination of Cd²⁺ was fabricated by modifying silica sol with dodecyltrimethylammonium bromide (DTAB) and dithizone (DZ). Cd²⁺ formed a complex with DZ, changing the solution color immediately from purple to orange prior to detection using ultraviolet-visible spectrophotometry and a customized Cd analyzer for the precipitate. Under the optimum conditions, the developed Cd²⁺ sensor had a linear range of 0.01–0.25 mg L⁻¹, a low limit of detection of 5.0 μg L⁻¹, and outstanding repeatability. This sensor also showed good precision, with the relative standard deviations of less than 2.59% and 3.24% for the intra- and inter-day data, respectively. The proposed colorimetric method was successfully applied to determine Cd²⁺ in environmental water samples, and the results were comparable to those obtained using standard atomic absorption spectrometry. Moreover, quantitative analysis was conducted using the customized Cd analyzer to estimate the color intensity change, without requiring sophisticated scientific instruments. This colorimetric sensor can be used for the portable, cost-effective, and rapid on-site detection of Cd²⁺ in environmental water samples.

This work demonstrates the facile one step hydrothermal synthesis of carbon dots doped with nitrogen and sulfur (SCDs). The carbon dots have various uses, including their use as molecular payloads for antioxidant and drug delivery purposes. The sizes of the CDs were determined using transmission electron microscopy (TEM), which revealed an average size of 4.2 nm. The successful sulfur doping was confirmed by Fourier-transform infrared (FTIR) spectroscopy and X-ray photoelectron spectroscopy (XPS), which identified typical functional groups and elemental composition. UV-vis and photoluminescence (PL) spectroscopy revealed a wide absorption peak at 280 nm and a pronounced blue emission at 440 nm. Colloidal stability was confirmed by dynamic light scattering (DLS) and zeta potential analysis. The antioxidant characteristics were evaluated through the use of electron paramagnetic resonance (EPR) spectroscopy, which confirmed a notable ability to scavenge radicals which revealed more than 80% radical scavenging capability. The SCDs also showed nontoxic behavior against living cells. The findings emphasize the potential of SCDs in the fields of bioimaging, drug delivery, and as potent antioxidant agents.

In the present work, we propose GaGeX₂ (X = N, P, As) monolayers and explore their structural, vibrational, piezoelectric, electronic, and transport characteristics for multifunctional applications based on first-principles simulations. Our analyses of cohesive energy, phonon dispersion spectra, and ab initio molecular dynamics simulations indicate that the three proposed structures have good energetic, dynamic, and thermodynamic stabilities. The GaGeX₂ are found as piezoelectric materials with high piezoelectric coefficient d₁₁ of −1.23 pm V⁻¹ for the GaGeAs₂ monolayer. Furthermore, the results from electronic band structures show that the GaGeX₂ have semiconductor behaviours with moderate bandgap energies. At the Heyd–Scuseria–Ernzerhof level, the GaGeP₂ and GaGeAs₂ exhibit optimal bandgaps for photovoltaic applications of 1.75 and 1.15 eV, respectively. Moreover, to examine the transport features of the GaGeX₂ monolayers, we calculate their carrier mobility. All three investigated GaGeX₂ systems have anisotropic carrier mobility in the two in-plane directions for both electrons and holes. Among them, the GaGeAs₂ monolayer shows the highest electron mobilities of 2270.17 and 1788.59 cm² V⁻¹ s⁻¹ in the x and y directions, respectively. With high electron mobility, large piezoelectric coefficient, and moderate bandgap energy, the GaGeAs₂ material holds potential applicability for electronic, optoelectronic, piezoelectric, and photovoltaic applications. Thus, our findings not only predict stable GaGeX₂ structures but also provide promising materials to apply for multifunctional devices.

Inflammation is a complex process with many contributing factors, and it often causes pain. The pathophysiology of pain involves the release of inflammatory mediators that initiate pain sensation, as well as edema and other inflammation hallmarks. Selenium-containing compounds (OSe) are very promising for developing new medicines because they can treat many different diseases. In this study, we estimated the anti-inflammatory properties of maleanilic and succinanilic acids containing selenium (OSe). These molecules were designed by combining different strategies to enhance their anti-inflammatory properties. Hence, the anti-inflammatory impacts of compounds 8, 9, 10, and 11 were pursued using inflammatory markers COX-2, IL-1β, and IL-6. Notably, it was revealed that compounds 8, 9, 10, and 11 downregulated COX-2, IL-1β, and IL-6 by (2.01, 1.63, 2.26, and 2.05), (1.42, 1.64, 1.93, and 2.59), and (1.67, 2.54, 2.22, and 4.06)-fold changes, respectively. Moreover, molecular docking studies were conducted on compounds 8, 9, 10, and 11 to pursue their binding affinities for the COX-2 enzyme. Notably, very promising binding scores of compounds 8, 9, 10, and 11 towards the binding site of the COX-2 receptor were attained. Additionally, more accurate molecular dynamics simulations were performed for 200 ns for the docked complexes of compounds 8, 9, 10, and 11 to confirm the molecular docking findings, which ignore the protein's flexibility. Therefore, the exact stability of the N-amidic acids OSe compounds 8, 9, 10, and 11 towards the binding pocket of the COX-2 enzyme was examined and explained as well. Also, the MM-GBSA binding energy was calculated for equilibrated MD trajectory, and 200 snapshots were selected with a 50 ps interval for further analysis. Accordingly, the investigated compounds can be treated as prominent lead anti-inflammatory candidates for further optimization.

The clinical outcome of spinal fusion surgery is closely related to the success of bone fusion. Nowadays, the interbody cage which is used to replace the disc for spinal fusion is expected to have biological activity to improve osseointegration, especially for the aging and osteoporotic patients. Here, through micro-arc oxidation and hydrothermal treatment (MAO + HT), a bioactive CaP coating with micro/nano multilevel morphology was developed on 3D printed Ti6Al4V alloy then verified in vitro and in sheep anterior cervical decompression fusion model systematically. In vitro studies have confirmed the positive effects of characteristic micro/nano morphology and hydrophilicity of the coating formed after surface treatment on the adhesion, proliferation, and osteogenic differentiation of osteoblast precursor cells. Furthermore, the MAO + HT treated interbody cage showed a closer integration with the surrounding bone tissue, improved kinetic stability of the implanted segment, and significantly reduced incidence of fusion failure during the early postoperative period, which indicated that such a surface modification strategy is applicable to the biomechanical and biological microenvironment of the intervertebral space.

The oxidative desulfurization of dibenzothiophene in model and real fuel has been investigated by developing an environmentally sustainable catalyst H₄SiW₁₂O₄₀@f-kaolinite. The catalyst was synthesized by modifying kaolinite clay with (3-aminopropyl)triethoxysilane (f-kaolinite) followed by immobilizing silicotungstic acid hydrate (H₄SiW₁₂O₄₀) onto its surface. The successful synthesis of the catalyst was characterized by Fourier transform infrared spectroscopy, Raman spectroscopy, UV-visible spectroscopy, X-ray diffraction, energy-dispersive X-ray spectroscopy, and scanning electron microscopy. The influence of variables i.e., catalyst dosage, temperature, and oxidant concentration on the conversion of dibenzothiophene was optimized by Box–Behnken design. The highest sulfur reduction (from 1000 to 78.3 ppm, with a conversion rate of 92.17%) was achieved at 70 °C, using a catalyst dosage of 70 mg and 8 mL of H₂O₂ in a model fuel. ANOVA analysis indicated that the quadratic model (R² = 0.99) was well-fitted for dibenzothiophene conversion, with a p-value of 0.2302 suggesting no statistically significant lack of fit compared to pure error. Furthermore, the H₄SiW₁₂O₄₀@f-kaolinite demonstrated a reduction of dibenzothiophene concentration from 354 ppm to 224 ppm in a real fuel oil sample. The heterogeneous nanocatalyst showed remarkable stability, maintaining its elemental structure after five cycles without significant efficiency loss, promoting environmental sustainability.

Cellulose, an environmentally friendly material, is abundantly available in Thailand as pulp and has significant potential for use in sustainable plant protection; however, the raw material is not directly suitable for such applications. To address this, colloidal cellulose with high water dispersibility was synthesised by treating Eucalyptus pulp with sulphuric acid (H₂SO₄). The optimised conditions involved a 24 hour treatment, producing colloidal cellulose with an average particle size of 0.57 ± 0.03 μm, the smallest size achieved. The cellulose morphology, consisting of submicron and nanoscale fragments and particles, was confirmed by transmission electron microscopy, field-emission scanning electron microscopy, and dynamic light scattering analyses. This microstructural transformation, driven by H₂SO₄-induced gelatinization and regeneration, led to decreased crystallinity, as observed in X-ray diffraction patterns and infrared spectra. The formation of colloidal cellulose as a film with adhesive properties on complex plant surfaces is facilitated by hydrogen bonding and hornification mechanisms. Additionally, colloidal cellulose demonstrated high compatibility with cuprous oxide, which was used as a model agricultural protective agent, showing a reduction of over 99% in E. coli and S. aureus abundance, highlighting the potential of colloidal cellulose as a sustainable coating agent or adjuvant in agricultural protection strategies.

Aluminum alloys are widely sought for different applications due to their high strength-to-weight ratio. Most often this increased strength of the alloy is achieved by specific alloying elements and heat treatment processes which give rise to second phases intermetallic particles (IMPs) also known as intermetallic compounds (IMCs). These second phases play a dominant role in the corrosion susceptibility of aluminum alloys. This review provides a systematic survey of the electrochemical, and galvanic corrosion behavior of IMPs in the context of aluminum alloys. A discussion of the electrochemical/galvanic corrosion behavior of selected/important intermetallic compounds that are commonly found in aluminum alloys such as the Q-phase (Al₄Cu₂Mg₇Si₈), π-phase (Al₈Mg₃FeSi₆), θ-phase (Al₂Cu), S-phase (Al₂CuMg), the β-phase (Mg₂Si), β-phase (Al₃Mg₂), δ (Al₃Li), η-phase (MgZn₂), and β-phase (Al₃Fe) is provided. In addition, the limitations in the electrochemical characterization of intermetallic compounds, the research gap, and prospects are also provided in addition to the phenomenon of galvanic polarity reversal and self-dissolution of IMPs.

A highly selective and sensitive fluorescent probe, RHOQ, was designed for the detection of Hg²⁺ by incorporating an 8-hydroxyquinoline moiety onto a rhodamine molecular platform with a suitable linker. In MeOH–Tris (20 mM, pH = 7.4, 1 : 9, v/v) buffer solution, RHOQ exhibited 550-fold fluorescence enhancement at 594 nm upon addition of Hg²⁺, with a fast response and a low detection limit (9.67 × 10⁻⁸ M). The 1 : 1 binding mode of RHOQ with Hg²⁺ was established using Job's plot, UV-Vis, and fluorescence spectroscopic titration methods. Furthermore, RHOQ was successfully applied for the detection of Hg²⁺ in living cells with good membrane permeability.

The unique capacity of certain plant endophytes to degrade organic pollutants has garnered considerable interest in recent years. However, it remains uncertain whether endophytes can maintain high degradation activity after in vitro culture and whether they can be used directly in the remediation of contaminated soils. This study reveals that resveratrol, a plant secondary metabolite, selectively boosts the degradation of polycyclic aromatic hydrocarbons (PAHs) by endophytic Methylobacterium extorquens C1 (C1) in vitro, while exerting negligible effects on the activity of indigenous soil bacteria. For the first time, a combined application of C1 and resveratrol was employed in the remediation of polycyclic aromatic hydrocarbon (PAH)-contaminated soil. The findings indicate that the sole use of resveratrol failed to promote the removal of PAHs by indigenous soil microorganisms, whereas sole application of C1 boosted Methylobacterium-related PAH-degrading bacterial abundance, enhancing PAH removal, yet concurrently reduced overall soil microbial diversity. The combination of resveratrol and C1 not only stimulated the PAH removal but also mitigated the impact of C1 on the soil microbial community structure when C1 was applied individually. Specifically, the optimal removal efficacy was achieved with a treatment combination of 5 mg kg⁻¹ resveratrol and 1.2 × 10⁷ CFU kg⁻¹ of C1, leading to a 130% and 231% increase in the removal of phenanthrene and acenaphthene, respectively, over a 15 days period. This study proposes a novel approach for the bioremediation of organic-contaminated soil by using the specific biological response of plant endophytic bacteria to secondary metabolites.