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Photochromic materials have attracted broad interest to enhance the anti-counterfeiting of commercial products. In order to develop anti-counterfeiting mechanically reliable composite materials, it is urgent to improve the engineering process of both the material and matrix. Herein, we report on the development of anti-counterfeiting mechanically reliable nanocomposites composed of rare-earth doped aluminate strontium oxide phosphor (RESA) nanoparticles (NPs) immobilized into the thermoplastic polyurethane-based nanofibrous film successfully fabricated via the simple solution blowing spinning technology. The generated photochromic film exhibits an ultraviolet-stimulated anti-counterfeiting property. Different films of different emissive properties were generated using different total contents of RESA. Transmission electron microscopy was utilized to investigate the morphological properties of RESA NPs to display a particle diameter of 3–17 nm. The morphologies, compositions, optical transmittance, and mechanical performance of the produced photochromic nanofibrous films were investigated. Several analytical methods were employed, including energy-dispersive X-ray spectroscopy, scanning electron microscopy, and Fourier-transform infrared spectrometry. The fibrous diameter of RESA-TPU was in the range of 200–250 nm. In order to ensure the development of transparent RESA-TPU film, RESA must be prepared in the nanosized form to allow better dispersion without agglomeration in the TPU matrix. The luminescent RESA-TPU film displayed an absorbance intensity at 367 nm and two emission intensities at 431 and 517 nm. The generated RESA-TPU films showed an enhanced hydrophobicity without negatively influencing their original appearance and mechanical properties. Upon irradiation with ultraviolet light, the transparent nanofibrous films displayed rapid and reversible photochromism to greenish-yellow without fatigue. The produced anti-counterfeiting films demonstrated stretchable, flexible, and translucent properties. As a simple sort of anti-counterfeiting substrates, the current novel photochromic film provides excellent anti-counterfeiting strength at low-cost as an efficient method to develop versatile materials with high mechanical strength to create an excellent market as well as adding economic and social values.

Chemical and electrochemical techniques were used to evaluate the effect of expired paracetamil–Zn+2 systems (PC–Zn+2) as potential nontoxic inhibitor for the dissolution process of iron in 2.0 M s...

Synthesis for new Cu(II) complexes from acetamidopyridine derivitives and their characterization. Applying analytical, spectral and conformational techniques, the characterization for all new synthesizes, was achieved. Equimolar ratio (1:1) was proposed for all complexes in which the ligands behaved as bidentate toward copper center. The molar conductivity measurements defined state of acetate presence according to coordination sphere. Two structural forms were proposed for five complexes, square-planer and octahedral based on UV–Vis and ESR data. Conformational study was executed for all compounds by DFT method in Gaussian 09 under 6-31G basis set. The optimal structural forms were obtained besides other significant files (log, chk & fchk). Also, functional parameters were calculated, to put a well view about physical features. QSAR parameters were obtained from HyperChem program, also to assert on some characteristics. MOE-docking module, which considered the most powerful program simulates interaction of tested compound with biological systems, was also used to strengthen the study. The data extracted orient to great expectation for biological efficiency of complexes against breast cancer cells. The most shining point was the anticancer screening results, which reflect vigorous toxic behavior for most tested complexes against breast cancer cell line that actually exceeds than doxorubicin itself.

Synthesis for new pyrazolin derivatives, which oriented for coordination with Cr(III) ion then all new synthesizes were characterized with reliable techniques. Octahedral geometry was the only form suggested from bi-negative tetra-dentate mode of bonding within bi-nuclear complexes. Such offering is based on analytical and spectral tools (IR, UV–Vis and MS). TGA confirms and discriminates water molecules profiles with relative to coordination sphere. Practical and computational XRD patterns appeared having high extent of similarity attributing to nano-crystalline particulate sizes. Hirshfeld surface properties and the efficiency of molecular-contact in crystal-packing, were obtained upon Crystal explorer 3.1 software beside VESTA package. Some physical indices were estimated based on frontier energy gaps over optimized structures upon Gauss-view software. Computational simulation approach was implemented to monitor changes on cancer cell proteins after treatment by new Cr(III) complexes, for assessment. Promising antitumor activity might be expected for Cr(III)-L4, Cr(III)-L3 and Cr(III)-L2 complexes, based on exported interaction parameters. It is worthy to note that, in-vitro assay reflects an excellent cytotoxicity recorded for such three complexes, in excellent harmony with simulation suggestions.

The current work proposed a new green procedure that is not sophisticated to recognize and determine the Al(III) ions in multiple water samples. The suggested method was conducted based upon the direct immobilization of aurintricarboxylic acid reagent into the mesoporous silica nanospheres to shape a unique and novel solid sensor. Al(III)-ATA red-complex has been formed at pH 4.0 and spectrophotometrically measured at 525 nm. Moreover, the complexation was reversible, and the ATA sensor retained his functionality even after six-time reuse/cycles using EDTA as eluent. Univariate and multivariate (partial least squares 1, PLS-1) calibration techniques were utilized for calculating the figures of merit for the determination of the Al(III) ions. The obtained calibration curve was linear from 2.0 to 70 ppb Al(III) ions concentration. The developed method has a detection limit of 3.5 ppb. In addition, the ATA sensor showed high adsorption capacity value (118.53 mg/g) which gives it a great advantage to be applicable as nanocollector for trapping Al(III) ions. The novel ATA sensor showed high degree of selectivity, sensitivity, reproducibility, and stability. The current study explores the effectiveness of the ATA sensor for the first time to produce a green solid sensor to determine the trace amount of Al(III) in diverse water types; tap, mineral, river, well, and sea water.

Simple preparation of flame-retardant, photoluminescent, and superhydrophobic smart nanocomposite coating was developed and applied onto cotton fibres using the simple pad-dry-cure technique. This novel strategy involved the immobilization of rare-earth-doped aluminium strontium oxide (ASO; SrAl2 O4 :Eu+2 ,Dy+3 ) nanoparticles, environmentally friendly room temperature vulcanizing silicone rubber (RTV) and environmentally friendly Exolet AP422 (Ex). The fabrics were also able to produce a char film in the fire-resistant assessment, providing fibres with a self-extinguishing characteristic. Furthermore, the fire-retardant performance of the coated cotton samples remained resistant to washing over 35 laundry cycles. The superhydrophobicity of the treated fabrics was monitored to improve by increasing the photoluminescent phosphor nanoparticles. The produced transparent photoluminescent film displayed an absorption at 360 nm and an emission at 526 nm. The photoluminescent fabrics were observed to generate different colorimetric shades, including white, green-yellow and bright white as monitored by Commission Internationale de l'Eclairage laboratory colorimetric coordinates. Slow emissions were detected for the treated cotton fabrics as monitored by emission, ultraviolet-visible light absorption, lifetime, and decay time spectral profiles to indicate glow in the dark phosphorescence effect. Both comfort and mechanical properties of the coated fibres were evaluated by measuring their bending length and air permeability.

In this work, low-cost and readily available limestone was converted into nanolimestone chitosan and mixed with alginate powder and precipitate to form a triple nanocomposite, namely limestone—chitosan–alginate (NLS/Cs/Alg.), which was used as an adsorbent for the removal of brilliant green (BG) and Congo red (CR) dyes in aqueous solutions. The adsorption studies were conducted under varying parameters, including contact time, temperature, concentration, and pH. The NLS/Cs/Alg. was characterized by SEM, FTIR, BET, and TEM techniques. The SEM images revealed that the NLS/Cs/Alg. surface structure had interconnected pores, which could easily trap the pollutants. The BET analysis established the surface area to be 20.45 m2/g. The recorded maximum experimental adsorption capacities were 2250 and 2020 mg/g for CR and BG, respectively. The adsorption processes had a good fit to the kinetic pseudo second order, which suggests that the removal mechanism was controlled by physical adsorption. The CR and BG equilibrium data had a good fit for the Freundlich isotherm, suggesting that adsorption processes occurred on the heterogeneous surface with a multilayer formation on the NLS/Cs/Alg. at equilibrium. The enthalpy change (ΔH0) was 37.7 KJ mol−1 for CR and 8.71 KJ mol−1 for BG, while the entropy change (ΔS0) was 89.1 J K−1 mol−1 for CR and 79.1 J K−1 mol−1 BG, indicating that the adsorption process was endothermic and spontaneous in nature.

Four new 1: 1 ratio of Se+4, Nb+5, Ta+5, and Te+4 penicillinate complexes are synthesized in the reaction of penicillin potassium salt (Pin-G-K) with Se(IV), Nb(V), Ta(V), and Te(IV) chlorides. Structures of the synthesized complexes are characterized by elemental analysis, conductivity, magnetic susceptibility, IR, UV-Vis, 1H and 13C NMR, and mass spectra, SEM, TEM, and XRD. Diamagnetic and electronic spectral studies allow to elucidate the geometry of penicillinate chelates around central metal ions. The monomeric structures of Pin-G complexes with six or eight coordinated metal ions are proposed. The metal ions are coordinated toward Pin-G as tridentate chelates via the amide and β-lactam carbonyl, and monodentate carboxylate groups. According to powder XRD the complexes have crystalline to poly crystalline nature. In vitro antimicrobial activity of Pin-G complexes is tested against four bacteria pathogens: G− (Klebsiella and Escherichia coli) and G+ (Staphylococcus epidermidis and Staphylococcus aureus). Anti-tumor activity of the Pin-G complexes is assessed against human hepato cellular carcinoma (HepG-2) and human breast cancer (MCF-7) tumor cell lines.

In this paper, two new complexes of selenium caffeine, [Se(Caf)4], and zinc α-tocopherol, [Zn(α-Tpl)2(NO3)2], are synthesized. The structures of complexes are characterized by IR, Raman and 1H NMR spectra, scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray powder diffraction (XRD), and thermogravimetric (TG/DTG) analysis. According to conductivity measurements the complexes are non-electrolytes. Spectroscopic studies of Se0 caffeine complex indicate its monodentate coordination via nitrogen atom N9 at 1: 4 molar ratio metal-to-ligand. In [Zn(α-Tpl)2(NO3)2], α-Tpl chelate is coordinated as a monodentate ligand via oxygen atom of the hydroxyl group with 1: 2 metal-to-ligand molar ratio. The percentage scavenging activity of hydroxyl radical (IC50 = 0.21 and 0.32 µg/mL), DPPH (0.17 and 0.30 µg/mL) and superoxide anion scavenging activity (0.18 and 0.32 µg/mL) indicate that selenocaffeine complex is of higher potential antioxidant activity than zinc(II) α-tocopherol complex.

Herein, a novel carbon paste electrode incorporated with reduced graphene oxide (rGO) was electrochemically characterized for sensitive adsorptive voltammetric determination of oxfendazole (OXF) in veterinary formulations and spiked milk samples. On the electrode surface, oxfendazole showed a reversible electrooxidation behavior through a mixed adsorption-diffusion with the involvement of one-electron on the electroanalytical measurements and molecular orbital studies. Linear calibration curves were constructed within OXF concentration ranged from 1.75 to 1890.9 ng ml−1 with LOD value of 0.85 ng ml−1. Compared with the reported OXF sensor, the rGO based sensors showed improved sensitivity with measurement reproducibility and long operational lifetime and shelf lifetime. The fabricated sensors were applied for the quantification of oxfendazole in the local veterinary formulations and spiked milk samples with high accuracy and precision compared with the traditional spectrophotometric techniques.

The present work describes the fabrication and electrochemical characterization of a novel iron oxide nanopowder-based carbon paste electrodes (CPE) for the sensitive voltammetric quantification of midodrine (MD) in pharmaceutical formulations and biological fluids. At the electrode surface, the postulated reaction mechanism involved the irreversible oxidation of the terminal amino group of midodrine through the participation of two-electron as elucidated by the sweep rate studies and molecular orbital calculations. Calibration graphs were linear in the MD concentration range from 0.16 × 10-6 to 2.12 × 10-6 mol L-1 with LOD 0.04 × 10-6 mol L-1. Prolonged stability with an operational lifetime of more than 4 months and high measurement reproducibility were the promising futures of the fabricated sensors. The proposed electroanalytical approach was free from interference and suggested for assaying of midodrine in its pharmaceutical formulations and biological samples with recovery agreed with the official methods.

This article describes the synthesis of some novel sulfonamides having biologically active pyridine 21–28 . Starting with 4-(1-(2-(2-cyanoacetyl)hydrazono)ethyl)- N -ethyl- N -methylbenzenesulfonamide (2) , which was prepared from condensation of acetophenone derivative 1 with 2-cyanoacetohydrazide. Interaction of compound 2 with different aldehydes namely 4-fluorobenzaldehyde, 4-hydroxybenzaldehyde and 4- N , N -dimethylbenzaldehyde afforded the corresponding hydrazono-ethyl- N -ethyl- N -methylbenzene sulfonamides 18–20 respectively, which when reacted with malononitrile and ethyl cyanoacetate afforded compounds 21–26 respectively. These compounds 21–26 can be prepared by another reaction route by interaction of compounds 2 with arylidine malononitrile and arylidine ethyl cyanoacetate in refluxing dioxane in the presence of trimethylamine as catalyst. Interaction of compound 2 with malononitrile and ethyl cyanoacetate afforded oxopyridine derivatives 27 and 28 respectively. All the new prepared compounds were evaluated for their antitumor activities against the cell lines MCF-7 in comparison with the reference drug Doxorubicin using the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide (MTT) colorimetric assay. Compounds 25 , 21 , 23 with SI values of 9.72, 9.71, 8.81 respectively, exhibited better activity than doxorubicin (Dox) as a reference drug with SI value of 8.49. In addition, compounds 25 , 27 and 22 exhibited anti-bacterial activity against gram-negative bacteria ( Klebsiella pneumoniae ) with inhibition zones 22.6, 20.3 and 19.3 mm respectively, which were more active than gentamicin as a reference drug with inhibition zone 17.3 mm. Molecular Operating Environment (MOE) performed virtual screening using molecular docking studies of the synthesized compounds. The results indicated that some synthesized compounds suitable inhibitor against dihydrofolate reductase (DHFR) enzyme (PDB SD: 4DFR) with further modification.

A simple, low cost and efficient headspace sorptive solid phase microextraction (HS-SPME) method for determination of cyanide has been developed. The system comprises of a glass tube with two valves and a moveable glass slide fixed at its centre. It includes an acceptor phase polyurethane foam treated mercury (II) dithizonate [Hg(HDz) 2 –PUF] complex fixed inside by a septum cap in a cylindrical configuration (5.0 cm length and 1.0 cm diameter). The extraction is based upon the contact of the acceptor phase to the headspace and subsequently measuring the absorbance of the recovered mercury (II) dithizonate from PUFs sorbent. Unlike other HSSE, extraction and back – extractions was carried out in a closed system, thereby improving the analytical performance by preventing the analyte loss. Under the optimized conditions, a linear calibration plot in the range of 1.0–50.0 µmol L −1 was achieved with limits of detection (LOD) and quantification (LOQ) of 0.34, 1.2 µmol L −1 CN − , respectively. Simultaneous analysis of cyanide and thiocyanate in saliva was also performed with satisfactory recoveries.

This article describes the synthesis of some novel heterocyclic sulfonamides having biologically active thiophene 3, 4, 5, 6, coumarin 8, benzocoumarin 9, thiazole 7, piperidine 10, pyrrolidine 11, pyrazole 14 and pyridine 12, 13. Starting with 4-(1-(2-(2-cyanoacetyl)hydrazono)ethyl)-N-ethyl-N-methylbenzenesulfonamide (2), which was prepared from condensation of acetophenone derivative 1 with 2-cyanoacetohydrazide. The structures of the newly synthesized compounds were confirmed by elemental analysis, IR, 1H NMR, 13C NMR, 19F NMR and MS spectral data. All the newly synthesized heterocyclic sulfonamides were evaluated as in-vitro anti-breast cancer cell line (MCF7) and as in-vitro antimicrobial agents. Compounds 8, 5 and 11 were more active than MTX reference drug and compounds 12, 7, 4, 14, 5 and 8 were highly potent against Klebsiella pneumonia. Molecular operating environment performed virtual screening using molecular docking studies of the synthesized compounds. The results indicated that some prepared compounds are suitable inhibitor against dihydrofolate reductase (DHFR) enzyme (PDBSD:4DFR) with further modification.