Novel Deliberately Sensitive and Selective Tetrahydrozoline Voltammetric Sensors Integrated with a Copper Oxide Nanoparticle/Zeolite Platform.

The present study introduced a novel disposable screen-printed carbon electrodes (SPCEs) modified with copper oxide/zeolite nanostructures for eco-friendly selective differential pulse voltammetric quantification of tetrahydrozoline (THZ) in eyedrop samples and biological fluids. Modification of the electrode matrix with copper oxide nanoparticles/zeolite nanostructures (CuONPs/ZY) with their effective and synergistic electrocatalytic activity enhanced the electrode performance against electrooxidation of THZ at 0.960 V in BR at pH 9.0 with a diffusion-controlled reaction mechanism. The tentative oxidation mechanism based on molecular orbital calculations postulates the oxidation of THZ molecules through oxidation of a nitrogen atom five-membered ring and the participation of two electrons/protons in the electrode reaction. Linear calibration curves were illustrated within a wide THZ concentration range from 0.24 to 57.2 µg mL-1 recording a limit of detection (LOD) value of 0.0799 µg mL-1. The CuONPs/ZY/SPEs exhibited improved performance compared with the sole reported THZ sensor-based gold film-plated carbon paste electrodes, in addition to their high reproducibility of fabrication and measurement and prolonged shelf lifetime. Tetrahydrozoline was successfully assayed in the presence of excipients, degradation products, and chloramphenicol. The presented voltammetric sensor can be considered as an eco-friendly and reliable analytical approach for monitoring THZ residues in eye drop samples and biological fluids with high recovery compared with the official pharmacopeial analytical protocol. The presented sensors were assessed according to an EcoScale tool and also compared with the reported THZ sensor.

Facile synthesis of new metal-organic framework/chitosan composite sponge for Hg(II) removal: Characterization, adsorption efficiency, and optimization using Box-Behnken design.

The objective of this research was to develop a novel adsorbent to eliminate mercury (Hg(II)) from water. A unique citrate-crosslinked La-MOF/citrate crosslinked chitosan composite sponge (La-MOF@CSC composite sponge) was successfully synthesized in an acidic environment using a one-step technique. Modifying the composition of adsorbent materials is a commonly employed strategy to enhance adsorption capacity, particularly for materials composed of metal-organic frameworks. The study investigated the impact of the composite sponge on the adsorption and removal of Hg(II). The composite sponge exhibited a maximum adsorption capacity (qmax) for Hg(II) at 765.22 mg/g and an impressive high surface area of 1208 m2/g. Various factors influencing the adsorption capacity were taken into account in this study. The adsorption isotherm and kinetics were modeled using Langmuir and pseudo-second-order equations, respectively. Consistent with thermodynamics, the adsorption process was identified as spontaneous and endothermic. The quantities of adsorbed substances increased with rising temperature. The La-MOF@CSC composite sponge demonstrated the ability to be reused up to five times with satisfactory efficiency, retaining its chemical composition and exhibiting similar XRD and XPS data before and after each reuse. The interaction between heavy metals and the La-MOF/CSC composite sponge was examined. Optimization of the adsorption outcomes was conducted using the Box-Behnken design (BBD).

Preparation of green colorimetric pH sensor using Humulus lupulus L. (common hop) biomolecular extract for sweat monitoring.

Novel smart cotton diagnostic assay was developed toward onsite sensing of sweat pH variations for possible medical applications such as drug test and healthcare purposes. Humulus lupulus L. extract was obtained according to previously reported procedure. As reported by high-performance liquid chromatography (HPLC), the extract demonstrated the presence of hop acids, prenylchalcones, and prenylflavanones, which is responsible for the colorimetric changes. The extract was applied to cellulose fibers employing potassium aluminum sulfate as mordant. This was observed by the formation of mordant/xanthohumol nanoparticles onto cotton surface. The absorption spectra and CIE (Commission Internationale de l'Eclairage) Lab screening of the prepared cotton assay showed colorimetric changes in association with hypsochromic shift from 600 nm to 433 nm upon exposure to sweat simulant fluid (pH < 7). The biochromic activity of the xanthohumol-finished cotton depends mainly on the halochromic performance of the xanthohumol chromophore to show a colorimetric switch from yellow to white owing to intramolecular charge transfer in the xanthohumol molecule. No substantial defects were detected in gas-permeability and stiffness of the treated fabrics. Satisfactory fastness was approved for the xanthohumol-dyed diagnostic cotton assay.

Superficial and Inkjet Scalable Printed Sensors Integrated with Iron Oxide and Reduced Graphene Oxide for Sensitive Voltammetric Determination of Lurasidone.

The present work demonstrated the fabrication and the electrochemical characterization of novel printed electrochemical sensors integrated with an innovative nanosensing platform based on the synergic electrocatalytic effect of iron oxide nanoparticles (FeONPs) and reduced graphene oxide (rGO) for precise voltammetric determination of the antipsychotic drug lurasidone hydrochloride (LUH). The features of the electrode surface fabricated using the ordinary inkjet printer were characterized by scanning electron microscopy and electrochemical impedance spectroscopy. Among different ink formulations, integration of the printing ink with the ratio 15 mg FeONPs and 20 mg rGO was found to be the most appropriate for sensitive quantification of LUH in biological fluids and pharmaceutical formulations in the presence of LUH degradation products. Under the optimized experimental and electroanalytical parameters, the recorded square-wave voltammograms were correlated to LUH within the linear concentration ranging from 50 to 2150 ng mL-1 with detection limit and limit of quantification values of 15.64 and 47.39 ng mL-1, respectively. Based on the cyclic voltammograms recorded for LUH at different scan rates, the electrode reaction was assumed to be a diffusion reaction mechanism accompanied by the transfer of two electrons/protons through the oxidation of the five-membered ring nitrogen atom as assumed by the molecular orbital calculations carried out on the LUH molecule. The C max of LUH and the efficiency of the fabricated sensors enabled their clinical application for monitoring LUH in human biological fluids and pharmaceutical formulations in the presence of degradants for diverse quality control applications and green chemistry analysis.

Preparation of photoluminescent nanocomposite ink for detection and mapping of fingermarks.

Simple and efficient detection and mapping method based on a strong turn-on fluorescent pigment was developed for fingerprint analysis. We present a phosphor powder characterized by strong emission which is useful to achieve better fingerprint detection on multicolored or photoluminescent surfaces, such as currency notes characterized by optically changeable inks and highly fluorescent positions, because it offers better contrast and reduce the difficulty of background interference. Novel photochromic ink was prepared to establish a fingerprinted colorless film onto cellulose documents with green emission for anticounterfeiting applications as illustrated by photoluminescence spectra. Inorganic/organic nanoscale composite ink was prepared from rare-earth doped aluminate phosphor nanoparticles (PNPs; 27-49 nm) dispersed in a polyacrylic acid binding agent. PNPs were dispersed efficiently in polyacrylic acid to generate a colorless mark. The produced photochromic inks were spray-coated onto off-white paper sheets enclosing invisible fingermarks, and then exposed to thermofixation. Photochromic film was detected on paper surface presenting a transparent appearance under visible daylight and switchable to green under UV light. The CIE Lab parameters and photoluminescence spectra were studied under visible light and ultraviolet irradiation. The fingerprinted sheets showed fluorescence band at 517 nm upon excitation at 366 nm, showing a bathochromic shift and reversible photochromism without fatigue. The morphologies of pigment phosphor particles and fingerprinted sheets were inspected. The rheological properties of ink and mechanical behavior of the fingerprinted paper samples were explored. HIGHLIGHTS: Novel smart ink with alkaline-earth aluminate and polyacrylic acid was developed. Dual-mode fluorescent photochromism was presented for latent fingerprint analysis. Off-white fingerprinted films under daylight showed color change to green under UV. Fluorescence band monitored at 517 nm upon excitation at 366 nm. Fluorescent fingermark on paper sheets demonstrated good photostability.

Synthesis and characterization of Cu(II)-pyrazole complexes for possible anticancer agents; conformational studies as well as compatible in-silico and in-vitro assays.

New pyrazole derivatives were prepared and used to synthesize new bioactive agents from Cu(II) complexes that have OSN donors. Analytical and spectral (IR, UV-Vis, MS, 1H NMR, ESR & XRD) instruments characterized these complexes as well as their corresponding ligands. The bonding mode has been modified from ligand to ligand and the molar ratio for isolated complexes has also varied (1:1/1:2, M:L). The geometry of isolated complexes was commonly proposed, based on electronic transitions and ESR spectral-parameters. Via computational approaches, these structures were optimized using standard programs (Gaussian 09 & HyperChem 8.1) under the required basis set. Consequently, important physical characteristics have been obtained after finishing the optimization process. Inhibition behavior of all new synthesizes was studied by MOE module as in-silico approach which conducted versus the crystal structure of NUDT5 protein (6gru) of breast cancer cells. The interaction features summarized from docking processes, reveal effective inhibition validity for new Cu(II) complexes versus breast cancer cells. This according to scoring energy values and the stability of docking complexes in true interaction path (bond length ≤3.5 Å) particularly with Cu(II)-L3 and Cu(II)-L4 complexes. This reflects the possibility of successful behavior during practical application through in-vitro assay that intended in this study. Finally, the degree of toxicity of such new compounds to the breast cancer cell line was determined by in-vitro screening. To judge perfectly on their toxicity, in-vitro screening must compared to positive control as Doxorubicin (reference drug). IC50 values were calculated and represent Cu(II) complexes as outstanding cytotoxic agents which revealed superiority on the reference drug itself.