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Micro- and nanoplastics (MNPs) are increasingly recognized as emerging environmental stressors due to their persistence and bioactivity. Among them, poly(ethylene terephthalate) (PET) is one of the most abundant polymers detected in the human gastrointestinal system. This study examined the interaction between PET MNPs and pepsin, a key digestive enzyme, using multispectroscopic analyses and molecular docking simulations. Fluorescence spectroscopy showed concentration-dependent quenching of pepsin emission (0.01–0.5 mg/mL) due to static and dynamic processes, followed by enhancement at higher enzyme levels (≥ 1.0 mg/mL), indicating structural stabilization. UV-Visible (UV-VIS) and Fourier transform infrared (FTIR) spectra revealed attenuation of amide I–III bands, and the emergence of O–H and C═O peaks on PET surfaces, confirming conformational alterations in pepsin and oxidative modification of the polymer. Humification and aromaticity indices supported these changes, reflecting oxidative fragmentation at low pepsin levels and aromatic stabilization at higher ones. Rayleigh scattering and oxidative potential assays further demonstrated reduced aggregation and increased oxidative activity upon PET exposure. Molecular docking located PET oligomers near the catalytic residues Asp32 and Asp215, stabilized by hydrogen and π–π interactions. Collectively, PET MNPs induce a two-phase interaction with pepsin—initial oxidative quenching followed by conformational stabilization—highlighting the dual chemical and structural impacts of PET MNPs under gastric conditions.

A cost-effective and green synthetic route was adopted to synthesize zinc oxide nanoparticles (ZnO-NPs) using Alternanthera sessilis leaf extracts as a bioreductant and stabilizing agent. The synthesis of the nanoparticles was systematically confirmed using UV, FT-IR, XRD, FE-SEM, EDX, and TEM analyses followed by antioxidant potential and DNA interactions studies using both spectroscopic and molecular docking findings. The aqueous suspension of these nanoparticles exhibited maximum absorption at 361 nm. The FT-IR spectra revealed the different functional groups of the leaf extract responsible for the stabilization of the ZnO nanoparticles and the peak observed at 539 cm⁻¹ is designated to ZnO. The powder x-ray diffraction (XRD) pattern indicated the hexagonal crystal structure of ZnO-NPs with average crystallite size 22.85 nm. The uniform semispherical morphology is confirmed using FE-SEM and TEM analyses. The elemental composition of Zn-NPs was confirmed by EDX analysis. The 22.5 nm average particle size of Zn-NPs was measured by image J software. The −46.9 mV zeta potential value confirmed the stability of the synthesized Zn-NPs with an average particle size 22.4 nm. The antioxidant potential was studied using a DPPH assay, employing BHT as a standard. At 60 µg mL⁻¹, ZnO-NPs showed 65.2% DPPH scavenging activity as compared to standard BHT and a paired t-test was performed to compare the results. DNA interaction studies showed bathochromic shift of ZnO-NPs-DNA complex indicating intercalation binding with DNA strands. Significant DNA interaction ability and antioxidant potency were demonstrated by both experimental and docking studies, which have applications in various medical domains.

Schiff bases are a significant group of synthetic molecules with widespread applications because they can form stable metal complexes, with conjugated Schiff bases possessing tuneable opto-electronic properties. Conventional Schiff base syntheses often utilize harsh chemicals and conditions; therefore, an environmentally benign synthesis using natural acid catalysts from fruit juice extract has been reported and compared to a conventional synthesis. The Schiff base ligand (SBL) obtained from p-vanillin and 4-nitro-o-phenylene diamine was further complexed with transition metals to verify the ligand's metal complexing ability. The resultant metal complexes were stable. The structures of the Schiff base and its metal complexes were deduced based on FTIR, ¹H NMR, electronic absorption spectra, thermogravimetric analysis, and density functional theory (DFT) studies. The reactivity and nonlinear optical (NLO) properties of SBL were studied using computational methods. The results indicate that SBL is a potential NLO material for upcoming opto-electronic devices.

The slow evaporation solution growth method was employed to successfully grow single crystals of oxalic acid ammonium dichromate (OAAD). x-Ray diffraction (XRD) examination was utilized to verify the grown samples' structural integrity and crystallinity. Thorough spectroscopic analyses, such as FTIR spectroscopy and UV–vis–NIR absorption, demonstrated the presence of functional groups related to nonlinear optical (NLO) activity as well as an optical transparency window. To evaluate the material's suitability for photonic applications, linear optical metrics, including the absorption coefficient, refractive index, and optical band gap, were computed. The Kurtz–Perry powder approach was implemented to assess nonlinear optical behavior, and the results validated the efficiency of second harmonic generation (SHG), indicating a high NLO response. The effective relative second harmonic generation efficiency of OAAD is 0.93 times greater than that of the reference material KDP. The broad band gap, demonstrable SHG efficiency, and good optical transparency of OAAD crystals highlight their potential as prospective candidates for advanced photonic and optoelectronic devices.

An improved, novel, and efficient three-step synthetic process for the production of solriamfetol hydrochloride (1), an anti-narcolepsy medication designed to address excessive daytime sleepiness, has been disclosed. This method achieves an overall yield of 82% and demonstrates purity exceeding 99.95%, as confirmed by HPLC analysis. The superlative reaction conditions were identified by assessing the impurity profile and its formation during the synthesis. Six significant process-related impurities were identified and characterized, with optimizations resulting in a reduction of impurity levels below 0.05%, thereby ensuring compliance with ICH guidelines (ICH Q3A/B guidelines). The improved three-step synthetic protocol for Solriamfetol hydrochloride, substantially free from impurities, employs milder reaction conditions, a shorter cycle time, and the use of non-hazardous reagents, resulting in enhanced process safety. The developed synthesis method is robust, cost-effective, reproducible, and suitable for commercial production. The high purity (HPLC purity: 99.95%) of the final Solriamfetol hydrochloride (API) enhances product safety by minimizing potential impurities to meet a regulatory-compliant approach for the large-scale manufacture of Solriamfetol hydrochloride with improved quality and consistency.

In this study, thirteen derivatives of 3-aryl-4-hydroxy-6-methyl-2H-pyran-2-one (3a–3m) were rationally designed and synthesized as potential tyrosinase inhibitors. All synthesized structures were confirmed by ¹H NMR, ¹³C NMR, ESI–MS, IR, and elemental analysis. In the next step, it was found that compounds (3i) and (3j) exhibit the most potent tyrosinase inhibitory activities, with IC₅₀ values of 1.56 ± 0.21 and 1.82 ± 0.11 µM, respectively, and significantly outperform the reference inhibitor, kojic acid (IC₅₀ = 9.3 ± 1.27 µM). Antioxidant evaluation using the DPPH assay revealed weak radical scavenging activities (22.97%–36.47%) of all derivatives, suggesting that their inhibitory action is likely unrelated to antioxidant properties. Kinetic studies indicated that compound (3i) acts as a mixed-type inhibitor with an inhibition constant (K_i) of 2.2 µM. Molecular docking studies demonstrated favorable binding interactions of compounds (3i) and (3j) within the tyrosinase active site, involving coordination with copper ions and hydrogen bonding with key residues. These findings were further validated by molecular dynamics (MD) simulations, which confirmed the structural stability of the 3i-tyrosinase complex over a 100 ns simulation period. Overall, compounds (3i) and (3j) represent promising leads for the development of novel tyrosinase inhibitors for potential use in pharmaceutical, cosmetic, and food industry applications.

Silver nanostructures are extensively studied due to their unique properties and broad applicability. This work investigates the optical properties and field-enhancement potential of silver nanoplates (Ag-NPlates) synthesized via a two-step method. Optical extinction spectroscopy (OES) combined with theoretical analysis characterized the suspensions’ size distribution, morphology, and spectral behavior, complemented by TEM analysis. Both techniques revealed that the concentration of silver spherical nanoparticle seeds (Ag-Seeds) used critically influences the resulting Ag-NPlate characteristics. Decreasing the Ag-Seed concentration induces an infrared shift in the main plasmon peak compared to pure Ag-Seeds, corresponding to increased NPlate size. Size distributions centered at edge lengths of 12–15 nm and 34–36 nm were observed, yielding plasmon peaks at 543 nm (higher seed concentration) and 815 nm (lower seed concentration), respectively. Furthermore, the Ag-NPlates utility for sensing was demonstrated by successfully detecting brilliant blue dye (BB) using surface-enhanced Raman spectroscopy (SERS) upon their incorporation into an agarose gel.

Sodium-ion batteries (SIBs) are an appealing alternative to lithium-ion technology, particularly for stationary energy storage, due to their lower cost, greater resource availability, and environmental sustainability. However, the cost advantages of stationary SIBs are inadequate to ensure widespread commercial use. Sodium ions have slower ionic transit and a lower energy density than lithium ions due to their bigger size and atomic weights. This constraint, however, can be overcome by the high-rate capability of sodium-based materials. SIB's key characteristics include high rate capability, compatibility for all climates, and total recyclability, which, when combined with cost savings, make them ideal for large-scale energy storage systems. As a result, SIBs offer great potential for real-world applications. Current SIBs have specific capacities ranging from 100 to 150 mAh/g and energy densities of around 100–150 Wh/kg. Although these figures are lower than those for high-performance lithium-ion batteries (LIBs), current research is gradually closing the gap. One of the primary goals for SIBs is to increase energy density to more than 200 Wh/kg and extend cycle life beyond 2000 cycles. Advanced cathode materials, like sodium manganese-based compounds and sodium iron phosphate, are being studied, as well as new anode materials like hard carbon. Looking ahead, the future of SIBs is bright. According to BloombergNEF, SIBs might grab 23% of the stationary storage market by 2030, equivalent to more over 50 GWh. However, if technology improvements speed and production processes are optimized using equipment similar to that used in LIBs, these forecasts may be exceeded.

Steroids, commonly containing a distinct four rings carbon scaffold, are an important class of natural products with diverse biofunctions, which mainly include plant sterols, bile acids, cardiac glycosides, steroid saponins, steroid alkaloids, etc., and have aroused growing interest in the fields of bioorganic and pharmaceutical research. To facilitate the development of novel chemical entities with potential cytotoxic activity, a series of skeleton diversity–guided steroid-thiazoline conjugates were designed and synthesized. All target compounds were evaluated for their in vitro inhibitory activity against human melanoma (A875) and hepatocellular carcinoma (Huh7) cell lines. The results showed that most of the newly synthesized compounds exhibited potent cytotoxic effects compared to 5-fluorouracil (5-FU). Furthermore, comprehensive structure-activity relationship analyses, supported by inhibition data and in silico studies, revealed that the nature of the steroidal scaffold significantly influences biological activity.