Dispersive micro-solid phase extraction (D-µSPE) of nickel on activated nanodiamonds@Bi2WO6 nanocomposite from water and food samples.

This study presents an original nano-sorbent using activated nanodiamonds@Bi2WO6 to separate and enrich nickel ions from water and food samples. FTIR, XRD, FE-SEM, FE-SEM-EDX, EDS-TEAM, TGA, and BET were used to characterize the nanocomposite. It has a large surface area, active functional groups, and better reactivity. Ni(II) ions were determined as Ni(II)-PADAP chelates using UV-VIS spectroscopy. The parameters were studied and optimized, including pH (6), eluent type and volume (1 mL), ligand quantity (10 µg), sorbent dosage (20 mg), and contact time (1 min). The method has a low limit of detection (LOD) of 1.6 µg L-1, a limit of quantification (LOQ) of 5.3 µg L-1, a relative standard deviation of 4.5%, and a preconcentration factor of 10. The method was validated by applying to certified reference materials (BCR estuarine water 505 and 1573a NIST). The method was successfully applied to tap waters, industrial waste waters, and vegetables.

Micro solid phase extraction of lead and cadmium using functionalized nanodiamonds@CuAl2O4@HKUST-1 nanocomposite for FAAS analysis in food and water samples.

This study focuses on the development and application of a novel nanocomposite (functionalized nanodiamonds@CuAl2O4@HKUST-1)-based µ-SPE method for the sensitive and selective extraction of Pb and Cd from food and water samples. The technique offers high sensitivity and selectivity, allowing accurate measurement of these metals at trace levels. The detection limit is 0.031 µg kg-1 for Cd and 0.052 µg kg-1 for Pb, with a relative standard deviation of 1.7 % for Cd and 4.8 % for Pb. The method was successfully applied to real samples and efficiently quantified Pb and Cd in food and natural water samples. The highest concentrations were found in red lentils (0.274 µg kg-1 Pb) and fresh mint (0.197 µg kg-1Cd), but still below recommended limits set by FAO/WHO (300 µg kg-1 for Pb and 200 µg kg-1 for Cd). It promises to ensure food safety, monitor environmental contamination, and informs regulatory decisions to protect public health.

Nanodiamond (ND)-Based ND@CuAl2O4@Fe3O4 electrochemical sensor for Tofacitinib detection: A unified approach to integrate experimental data with DFT and molecular docking.

Tofacitinib (TOF) is gaining recognition as a potent therapeutic agent for a variety of autoimmune disorders, including rheumatoid arthritis and psoriasis. Ensuring precise drug concentration control during treatment necessitates a rapid and sensitive detection method. This study introduces a novel electrochemical sensor employing a composite of nanodiamond (ND), copper aluminate spinel oxide (CuAl2O4), and iron (II, III) oxide (Fe3O4) as modified materials for efficient TOF detection. Extensive analyses using physicochemical and electrochemical techniques were carried out to characterize the morphological, structural, and electrochemical properties of the ND@CuAl2O4@Fe3O4 composite. Thereafter, various voltammetric methods were utilized to evaluate the electrochemical behavior of the ND@CuAl2O4@Fe3O4-modified glassy carbon electrode (GCE) concerning TOF determination. The fabricated electrode showcased superior performance in electrochemical TOF detection in a buffered solution (pH = 5), achieving a remarkably low detection limit of 7.8 nM and a linear response from 0.05 µM to 13.21 µM. Furthermore, applying the modified electrode as an electrochemical sensor exhibited exceptional selectivity, stability, and practicality in determining TOF in pharmaceutical and biological samples. Alongside the sensor development, this study conducted a thorough investigation using Density Functional Theory (DFT) for the geometry optimization of TOF and the TOF-ND complex. Consequently performed molecular docking studies using Janus Kinase 1 (JAK1) (PDB ID: 3EYG) and JAK3 (PDB ID: 3LXK) indicated higher interaction of the TOF-ND conjugate with the JAKs, reflected by binding energies of -12.9 kcal/mol and -11.7 kcal/mol for JAK1 and JAK3 respectively, compared to -7.0 kcal/mol and -6.9 kcal/mol for TOF alone. These findings illustrate the potential of the ND-based ND@CuAl2O4@Fe3O4 composite as a proficient sensing material for TOF detection and the merits of DFT in providing a detailed understanding of the interactions at play. This pioneering research holds promise for real-time TOF monitoring, which will advance personalized treatment strategies and improve therapeutic outcomes for patients with autoimmune disorders.

A magnetic solid phase extraction procedure for Pb(II) at trace levels on magnetic Luffa@TiO2 in food and water samples.

A novel magnetic Luffa@TiO2 sorbent was synthesized and characterized by using XRD, FTIR and SEM techniques. Magnetic Luffa@TiO2 was used for solid phase extraction of Pb(II) in food and water samples prior to its flame atomic absorption spectrometric (FAAS) detection. The analytical parameters such as pH, adsorbent quantity, type and volume of eluent, and foreign ions were optimized. Analytical features such as the limit of detection (LOD) and the limit of quantification (LOQ) of Pb(II) are 0.04 µg L-1 and 0.13 µg L-1 for liquid samples and 0.159 ng/g and 0.529 ng/g for solid samples, respectively. The preconcentration factor (PF) and relative standard deviation (RSD%) were found 50, and 4 % respectively. The method was validated by using three certified reference materials (NIST SRM 1577b bovine liver, TMDA-53.3 and TMDA-64.3fortified water). The presented method was applied to lead contents of some food and natural water samples.