RSC Advances最新文献

Heterocyclic compounds represent a prominent class of molecules with diverse pharmacological activities. Among their therapeutic applications, they have gained significant attention as carbonic anhydrase (CA) inhibitors, owing to their potential in the treatment of various diseases such as epilepsy, cancer and glaucoma. CA is a widely distributed zinc metalloenzyme that facilitates the reversible interconversion of carbon dioxide and bicarbonate. This reaction is essential for numerous physiological and pathological processes. In humans, CA exists in sixteen different isoforms, labeled hCA-I to hCA-XV, each distributed across various tissues and organs and involved in crucial physiological functions. Clinically utilized CA inhibitors, such as brinzolamide, dorzolamide and acetazolamide, exhibit poor selectivity, leading to undesirable side effects. A significant challenge in designing effective CA inhibitors is achieving balanced isoform selectivity, prompting the exploration of new chemotypes. This review compiles recent strategies employed by various researchers in developing CAIs across different structural classes, including pyrazoline, quinoline, imidazole, oxadiazole, pyrimidine, coumarin, chalcone, rhodanine, phthalazine, triazole, isatin, and indole. Additionally, the review summarizes structure–activity relationship (SAR) analyses, isoform selectivity evaluations, along with mechanistic and in silico investigations. Insights derived from SAR studies provide crucial directions for the rational design of next-generation heterocyclic CA inhibitors, with improved therapeutic efficacy and reduced side effects. To the best of our knowledge, for the first time, we have comprehensively summarized all known isoforms of CA in relation to various heterocyclic motifs. This review examines the use of different heterocycles as CA inhibitors, drawing on research published over the past 11 years. It offers a valuable resource for early-career researchers, encouraging further exploration of synthetic heterocycles in the development of CA inhibitors.

In recent years, inorganic perovskite materials based on metallic halides have attracted significant attention due to their non-toxicity and ease of synthesis, making them suitable for various applications. This article describes the slow evaporation approach at room temperature for the fabrication of a non-toxic inorganic perovskite based on metallic halide Cs₂ZnCl₄. This compound crystallizes in the orthorhombic phase of the Pnma space group, as confirmed by room temperature X-ray diffraction. Through SEM-EDX studies, the morphological distribution and grain size of the Cs₂ZnCl₄ crystal were determined. Optical investigations of our compound in the 200–800 nm wavelength range indicate that the direct band gap has a value of around 3.80 eV. The photoluminescence analysis reveals the highest emission peak at around 340 nm. By employing the Cauchy law in ellipsometry spectroscopy, the refractive index (n) and the extinction coefficient (k) were determined. Moreover, a fluorescence image of Cs₂ZnCl₄ powder was captured using a confocal microscope. The electrical properties, including the dielectric constant, the loss factor, and the electrical modulus, have been determined in the temperature range of 313 to 433 K. Utilizing the Maxwell–Wagner effect as proposed by the Koop theory, the thermal variation of permittivity has been interpreted. The Kohlrausch–Williams–Watts equation (KWW) was used to assess the asymmetric curves of the electrical modulus.

Y-modified perovskite-type oxides BaCe_1−xY_xO_3−δ (x = 0–0.30) were synthesised and used as supports for cobalt catalysts. The influence of yttrium content on the properties of the support and catalyst performance in the ammonia synthesis reaction was examined using PXRD, STEM-EDX, and sorption techniques (N₂ physisorption, H₂-TPD, CO₂-TPD). The studies revealed that the incorporation of a small amount of yttrium into barium cerate (up to 10 mol%) increased specific surface area and basicity. The catalyst testing under conditions close to the industrial ones (T = 400–470 °C, p = 6.3 MPa, H₂/N₂ = 3) showed that the most active catalyst was deposited on a support containing 10 mol% Y. The NH₃ synthesis reaction rate was 15–20% higher than that of the undoped Co/BaCeO₃ catalyst. The activity of the catalysts decreased with further increasing Y content in the support (up to 30 mol%). However, all the studied Co/BaCe_1−xY_xO_3−δ catalysts exhibited excellent thermal stability, over 240 h of operation. The particularly beneficial properties of the catalyst containing 10 mol% of Y were associated with the highest basicity of the support surface, favourable adsorption properties (suitable proportion of weakly and strongly hydrogen-binding sites), and preferred size of cobalt particles (60 nm). The Co/BaCe_0.90Y_0.10O_3−δ catalyst showed better ammonia synthesis performance compared to the commercial iron catalyst (ZA-5), giving prospects for process reorganisation towards energy-efficient ammonia production.

Bisphenol A (BPA) raises concerns among the scientific community as it is one of the most widely used compounds in industrial processes and a component of polycarbonate plastics and epoxy resins. In this review, we discuss the mechanism of BPA toxicity in food-grade plastics. Owing to its proliferation in the aqueous environment, we delved into the performance of various biological, physical, and chemical techniques for its remediation. Detailed mechanistic insights into these removal processes are provided. The toxic effects of BPA unravel as changes at the cellular level in the brain, which can result in learning difficulties, increased aggressiveness, hyperactivity, endocrine disorders, reduced fertility, and increased risk of dependence on illicit substances. Bacterial decomposition of BPA leads to new intermediates and products with lower toxicity. Processes such as membrane filtration, adsorption, coagulation, ozonation, and photocatalysis have also been shown to be efficient in aqueous-phase degradation. The breakdown mechanism of these processes is also discussed. The review demonstrates that high removal efficiency is usually achieved at the expense of high throughput. For the scalable application of BPA degradation technologies, removal efficiency needs to remain high at high throughput. We propose the need for process intensification using an integrated combination of these processes, which can solve multiple associated performance challenges.

Facile adjustment of the behavior of dual cross-linked polymer-ionic liquid composites (PICs) for stretchable electronics was achieved via solution blending of two copolymers having the same monomer pairs. Two poly(docosyl acrylate-r-tert-butyl acrylate) (poly(A22-r-tBA)) copolymers with different molar ratios were synthesized and solution-cast with ionic liquids (ILs) to fabricate ternary PICs. The phase behavior and the thermal and structural properties of the composites were investigated by varying the mixing ratio, providing insights into the cross-linking mechanisms. The observed changes enabled systematic modulation of the stretchability, thermal stability, and self-healing capability of PICs, which are crucial attributes of wearable devices. Mechanically tough and conductive PICs were utilized in fabricating strain sensors capable of detecting human motion.

Gold nanoparticles (AuNPs) exhibit different physical properties compared to small molecules, bulk materials and other nanoparticles. Their synthesis using plant extracts, particularly polyflavonoids as phytoreductants, for the conversion of Au(III) into Au(0) has been reported. In this study, AuNPs were synthesized with extracts, sterols and pure compounds derived from marine sponges using gold(III) chloride trihydrate. Extracts, hexane (JDH) and ethyl acetate (JDE), sterols (JC-2) and jaspamide were obtained from Jaspis diastra. Pure compounds, namely, contignasterol, ansellone A, motuporamines A and MN100 (a synthetic analog of pelorol), were also used. JC-2 was characterized using NMR and GC-MS, and the major constituent was determined to be β-sitosterol. β-Sitosterol has shown great promise as an anti-cancer molecule, but its poor aqueous solubility and bioavailability coupled with low targeting efficacy limit its therapeutic efficacy. Transmission electron microscopy (TEM) images revealed the formation of spherical AuNPs conjugated with JDH, JDE, JC-2, ansellone and contignasterol with average diameters of 21.1 ± 3.0 nm, 20.7 ± 2.1 nm, 26.2 ± 1.2 nm, 33.3 ± 5.1 nm and 30.8 ± 5.5 nm, respectively. No particle formation was seen with motuporamines A and MN100. Zeta potential values indicated that AuNPs-JC-2 was more stable than AuNPs-JDE, AuNPs-JDH and AuNPs-ansellone. Based on IC₅₀ values, the cytotoxicity of AuNPs-JDH increased in A172, TERA, HeLa and HepG2 cells but showed similar activity in HaCaT cells compared to JDH. The cytotoxicity of AuNPs-JDE decreased in A172 and HaCaT cells but increased in TERA1, HeLa and HepG2 cells compared to JDE. AuNPs-JC-2 showed enhanced cytotoxicity with a decrease in IC₅₀ values from 3.37 ± 0.19 μg mL⁻¹ to 0.52 ± 0.09 μg mL⁻¹ in A172 and from 2.28 ± 0.20 μg mL⁻¹ to 0.78 ± 0.28 μg mL⁻¹ in TERA1 compared to JC-2. The synergistic action of sterols in AuNPs-JC-2 seemed to favour enhanced anti-cancer activity. The presence of sterols increased the ability of transforming Au(III) into Au(0) to form AuNPs and further enhancing cellular uptake and, thus, anti-cancer activity. AuNPs-contignasterol displayed lower activity than contignasterol in the A172 cell line. No significant difference in activity was observed with AuNPs-ansellone A in the A172 and HaCaT cell lines compared to ansellone A.

Co_n−1TMO_n−2⁺ (n = 6–8), (TM = V, Cr, Mn, and Fe) clusters are investigated using density functional theory calculations. The transition metal atoms preferentially replace one Co atom at sites where the number of metal–oxygen bonds is maximized, forming more stable structures. The evaporation of a Co atom is the most fragile dissociation channel for both pure and doped species. Bare cobalt oxide clusters exhibit parallel spin ordering, whereas both parallel and antiparallel spin ordering are observed in the doped species. Notably, a ferromagnetic-to-ferrimagnetic transition occurs in the V-doped clusters, while the ferromagnetic behavior is enhanced in the Fe-doped species.

Retraction of ‘Highly sensitive cadmium sulphide quantum dots as a fluorescent probe for estimation of doripenem in real human plasma: application to pharmacokinetic study’ by Marwa F. B. Ali et al., RSC Adv., 2020, 10, 44058–44065, https://doi.org/10.1039/D0RA07960J.

Improper disposal of used dry cell batteries and the leaching of bisphenol A (BPA), a prevalent endocrine disruptor present in food packaging, into surface water pose a significant threat to both the environment and drinking water, threatening the sustainability of the ecosystem. Thus, it is imperative to manage detrimental e-waste and regularly monitor BPA using a sensitive and reliable technique. This study proposes a cost-effective reduced graphene oxide/zinc oxide (rGO/ZnO) nanohybrid, entirely synthesized from electronic waste, for electrochemically detecting BPA in an aqueous medium. Graphite and metallic Zn precursors obtained from discarded batteries were employed to synthesize rGO/ZnO. The successful characterization of the prepared rGO and rGO/ZnO nanohybrid was conducted through different state-of-the-art techniques. An rGO/ZnO-modified glassy carbon electrode (GCE) exhibited superior conductivity and a larger surface area. Voltammetric study at the rGO/ZnO-modified GCE successfully detected BPA in an aqueous medium, demonstrating a one-electron and proton pathway for BPA oxidation. The sensor demonstrated a linear response within the concentration range of 1–30 μM, with a limit of detection of 0.98 nM and sensitivity of 0.055 μA μM⁻¹. The developed electrode could also detect BPA in real water samples with reasonable recovery. These findings imply that the developed sensor has the potential to be a sensitive, practical, and economical monitoring system for BPA in water.

Distance-based detection (DbD) on paper-based microfluidic analytical devices (μPADs) has emerged as a promising, cost-effective, simple, and instrumentation-free assay method. Broadening the applicability of a new way of immobilization of reagent for DbD on μPADs (DμPADs) is presented, employing an ion exchange (IE) interaction of an anionic metallochromic reagent, 2-(5-bromo-2-pyridylazo)-5-[N-n-propyl-N-(3-sulfopropyl)amino]phenol (5-Br-PAPS), on the anion-exchange filter paper. The IE DμPADs demonstrate superiority over standard cellulose filter paper in terms of the degree of reagent immobilization, detection sensitivity, and clear detection endpoints due to the strong retention of 5-Br-PAPS. The study investigated various parameters influencing DbD, including 5-Br-PAPS concentrations (0.25–1 mM), buffer types (acetic acid–Tris, MES), buffer concentrations (20–500 mM), and auxiliary complexing agents (acetic, formic, and glycolic acids). Subsequently, the performance of 17 metals (Ag⁺, Cd²⁺, Co²⁺, Cr³⁺, Cu²⁺, Fe²⁺, Hg²⁺, La²⁺, Mn²⁺, Ni²⁺, Pb²⁺, Ti²⁺, Zn²⁺, Al³⁺, As³⁺, Fe³⁺, and V⁴⁺) was evaluated, with color formation observed for 12 metals. Additionally, the paper surface was examined using SEM and SEM-EDX to verify the suitability of certain areas in the detection channel for reagent immobilization and metal binding. This method demonstrates quantitation limits of metals in the low μg mL⁻¹ range, showing great potential for the rapid screening of toxic metals commonly found in herbal supplements and cosmetics regulated by the Food and Drug Administration (FDA). Thus, it holds promise for enhancing safety and regulatory compliance in product quality assessment. Furthermore, this method offers a cost-effective, environmentally sustainable, and user-friendly approach for the rapid visual quantification of heavy metals for in-field analysis, eliminating the need for complex instrumentation.