• Method for determination of Pb and Co in four kinds of cosmetics available at local markets in Saudi Arabia was described.· • Atomic absorption spectroscopy was conducted to measure the content of Pb and Co in the analyzed samples.· • Quality control of the data was performed using Standard Reference Materials [IAEA-V-10] hay powder.· • Cobalt content exceeded the permissible limits, while Pb within the permissible limits for all products except for kajal.· • There was no significant risk to the users of these brands of cosmetics.

The fractionation of 10 metals (As, Co, Cr, Cu, Mn, Ni, Pb, Se, V, and Zn) within labile fractions in shallow marine sediments collected from the coasts of Sabah and Sarawak, Malaysia, was evaluated. Spatial distribution revealed that coastal sediments from Sabah were approximately 10% higher in metal content than sediments from Sarawak. Risk assessment code, enrichment factor, and pollution accumulation index calculations were used to investigate the environmental hazards of elements. For the risk assessment code, the modified Tessier sequential extraction procedure was applied. The risk assessment code values showed that metal V recorded the lowest environment risk (~ 10%) while As, Co, Cr, Cu, Mn, and Zn exhibited medium risk (Risk assessment code range of 11%–30%). The element Ni displayed no risk (0.67%) to the environment, whereas Se and Pb recorded the highest risk with values of 47% and 52%, respectively. For the enrichment factor calculation, the continental crust data presented by Taylor (Taylor, Geochim Cosmochim Acta 28:1273–1285, 1964) were used as background, with metal Al used as a reference element. Results illustrated that most of the metals show enrichment (enrichment factor > 1). However, Se was considered extremely severe to the environment (enrichment factor > 50). While the pollution accumulation index calculation demonstrated that all metals under study can be considered as non-contaminant elements except for Ni, V, and Co. These findings indicated that marine sediments in Sabah are more polluted with metal contaminants than the sediments in Sarawak, despite both states having numerous active oil- and gas-related production facilities.

A pH-dependent electrochemical sensor based on nickel–cobalt oxide modified carbon nanotube fiber (NiCo–O@CNTF) has been fabricated via a simple electrochemical approach and utilized in the nonenzymatic detection of ascorbic acid (AA) with varying pH. Scanning electron microscopy (SEM), energy-dispersive electron microscopy (EDX), Raman, and FTIR were utilized to investigate the structural morphologies, elemental mapping, and electronic vibrational modes within the modified fiber (NiCo–O@CNTF) and revealed the successful fabrication of the electrode. Electrochemical characterization, including cyclic voltammetry and chronoamperometry, exhibited an enhanced anodic response in buffer solutions (varying pH), achieving a high sensitivity of 62.39 μA cm^–2 mM^–1, a low detection limit of 16 μM, and a rapid response time of 5 s at pH 8.0. These results highlight NiCo–O@CNTF as a flexible and disposable microelectrode platform for wearable AA sensing applications.

In aqueous and solid media, 2-HP-β/γ-CD inclusion complexes with poly aromatic hydrocarbon (PAH) Phenanthrene (PHN), Anthracene (ANT), Benz(a)pyrene (BaP), and Fluoranthene (FLT) were investigated for the first time. The inclusion complexes were characterized and investigated using fluorescence and ¹HNMR spectroscopy. The most prevalent complexes consisting of both guests and hosts were those with a 1:1 guest-to-host ratio. The stability constants for the complexes of PHN with 2-HP-β-CD and 2-HP-γ-CD were 85 ± 12 M⁻¹ and 49 ± 29 M⁻¹, respectively. Moreover, the stability constants were found to be 502 ± 46 M⁻¹ and 289 ± 44 M⁻¹ for the complexes of ANT with both hosts. The stability constants for the complexes of BaP with 2-HP-β-CD and 2-HP-γ-CD were (1.5 ± 0.02) × 10³ M⁻¹ and (9.41 ± 0.03) × 10³ M⁻¹, respectively. The stability constant for the complexes of FLT with 2-HP-β-CD was (1.06 ± 0.06) × 10³ M⁻¹. However, FLT was observed to form a weak complex with 2-HP-γ-CD. Molecular dynamic (MD) simulations were used to investigate the mechanism and mode of inclusion processes, and to monitor the atomic-level stability of these complexes. The analysis of MD trajectories demonstrated that all guests formed stable inclusion complexes with both hosts throughout the duration of the simulation time, confirming the experimental findings. However, the flexible Hydroxypropyl arms prevented the PAHs from being encapsulated within the cavity; however, a stable exclusion complex was observed. The main forces that influenced the complexation included van der Waals interactions, hydrophobic forces, and C–H⋯π interaction, which contribute to the stability of these complexes.

An ecofriendly green synthesis of silver nanoparticles using Echinops species is presented, with a comparative evaluation of their antibacterial efficacy and photocatalytic degradation performance.

This study endeavors to investigate and authenticate a proposed more sensitive and selective high-performance liquid chromatography with a fluorescence detector technique for the assessment of a binary formulation of Amlodipine (ADP) and Telmisartan (TMS). Both analytes were chromatographically separated by an optimized solvent system comprising acetonitrile and phosphate buffer at pH 4 (58:42, v/v), using Discovery ^® C18 reverse phase high-performance liquid chromatography column (150 mm). The fluorescence detector excitation and emission wavelengths were determined to be 240 and 440 nm, respectively. The experiment followed Plackett–Burman’s design to optimize chemigraphic experimental variables. To assess the linearity of the method, calibration curves were generated using 12.5–200 μg/mL for ADP and 0.5–10 μg/mL for TMS, with good correlation coefficients of r = 0.9980 and 0.9970, respectively. In addition, the limits of detection for ADP and TMS were 1.04 and 0.15 µg/mL, respectively, while the corresponding limits of quantification were 3.14 and 0.44 µg/mL. The accuracy of the technique was confirmed by high percentage recovery with low relative standard deviation for both within-day and between-day precision. The analysis of the two medications in their prescribed form (tablet) was executed, and the retrieval and relative standard deviation were computed, followed by the application of a t -test. The results of the tablet analysis indicated that the overall accuracy (mean ± relative standard deviation) of the method was 99.78% ± 0.90% for ADP and 100.99% ± 0.07% for TMS. Hence, the proposed high-performance liquid chromatography method can be utilized for regular quality control of binary formulations consisting of ADP and TMS.