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The Graphene-based functional structures with large surface areas, ease of functionalization/modification, and photothermal features are currently very attractive for cancer nanotherapy applications. The reduced Graphene Oxide (rGO) structures having moderate cytotoxicity have been used against human cancerous cells. We developed a water soluble rGO by heating with an aryl azide (a “green” reagent) followed by mild oxidation with aqueous alkaline KMnO4 yielding the c0lorless, water soluble rGO-arylaziridino-Mn (II) complex. The anti-cancer property of the compound was tested in human monocytic U937 cell line, CT26 murine colon carcinoma cell line and 4T1 murine breast cancer cell lines. rGOarylaziridino-Mn (II) complex significantly induced apoptosis in the above cells in a concentration dependent manner in vitro, similar to an effect of known anti-cancer drug Doxorubicin.

aims: In the present study, a hydromagnetic Williamson nanofluid passed through a stretching sheet embedded in a porous media is being analyzed by assuming the impact of thermal radiation and magnetic field on the flow properties. background: Previously, many researchers have studied nanofluid flow, but hydromagnetic Williamson nanofluid passed through a stretching sheet embedded in a porous media will be a new finding among all researchers. objective: Our objective is to study a hydromagnetic Williamson nanofluid passed through a stretching sheet embedded in a porous media is being analyzed by assuming the impact of thermal radiation and magnetic field on the flow properties. method: By using appropriate similarity transformation the governing equations with boundary conditions were converted into a dimensionless form. The derived ordinary differential equation was solved using Spectral local linearisation method. result: The outcomes indicate that velocity reduces with increase in Williamson, Porosity and Magnetic field parameters, whereas the concentration profile improves with these parameters. Entropy generation rate is also enhanced when the Reynolds number, concentration difference parameter and Brinkman number are increased. conclusion: The results have been validated with existing research and our results are found to be in excellent agreement. other: The study finds that good agreement is achieved.

A {Mn(NO)}6 complex, [Mn(TMPP2−)(NO)], upon reaction with 2 equivalents of O2− in THF affords [MnIII(OH)] complex via a putative MnIII–peroxynitrite intermediate. Detailed studies have shown the preference of NOD activity over SOD-like activity.

Fluorescence spectroscopic studies of a pair of new oxido-vanadium(V) compounds with biological thiols, such as homocysteine (Hcy), cysteine (Cys), and glutathione (GSH), have been investigated in this article. Despite notable progress in vanadium-thiol chemistry, no attention has been paid to exploring vanadium-based optical probes to study their interaction with biothiols. For this purpose, two oxido-vanadium(V) compounds, 1 and 2, have been prepared involving a tridentate ONO donor-based luminescent coumarin-derived ligand. Single crystal X-ray diffraction analysis, NMR (1H, 13C and 51V) spectroscopy, XPS, and DFT calculations have been used to establish their identities. The vanadium center in these compounds has a distorted octahedral environment. In compound 2, a methanol molecule is coordinated to the vanadium(V) center in the trans position of the terminal oxido moiety. The latter exerts a strong trans-labilizing influence on the coordinating methanol. Both 1 and 2 are weakly fluorescent. Photophysical investigations of the vanadium complexes in aqueous media at physiological pH (7.4) in the presence of various biothiols and amino acids showed significant fluorescence enhancement (83-fold) of the vanadium complexes, specifically with Hcy. The specific affinity of the complexes for Hcy remained unchanged even in the presence of other biothiols and amino acids. Kinetic investigation reveals pseudo-first order behavior of the compound with Hcy. Mechanistic studies have manifested that Hcy-induced reduction triggers the decomplexation of the vanadium compound, followed by hydrolysis and subsequent cyclization. Time-correlated single photon counting suggested that the radiative rate constant (kr) of 1 and 2 in the presence of Hcy serves as the prime factor for the fluorescence enhancement of the medium. Compound 1 has been tested efficiently for Hcy measurement in blood plasma rendering it suitable for practical applications.

Peroxynitrite (ONOO-) is an essential endogenous reactive oxygen species (ROS) generated in mitochondria under various pathological and physiological conditions. An increase in its level in mitochondria is related to numerous diseases. In this work, we have reported a series of hemicyanine-derived water-soluble colorimetric probes (1-4) to study their reactivity with various reactive oxygen, nitrogen, and sulfur species. Probes 1-4 are formed by conjugating 1,2,3,3-tetramethyl-3H-indolium iodide and 4-hydroxybenzaldehyde or its derivatives through an alkene linkage formed by the Knoevenagel reaction. The oxidative cleavage of the electron-rich double bond of the conjugated hemicyanine dye revealed a discerning affinity of 3 towards peroxynitrite among all reactive oxygen species. The rapid color change of 3 provides a sensitive and selective method for detecting peroxynitrite with a low detection limit of 180 nM. Notably, the water solubility of the probe displays excellent performance for the selective detection of peroxynitrite among ROS, reactive nitrogen (RNS)/sulfur species (RSS). UV-vis, 1H NMR, and 13C NMR spectroscopic data and results from theoretical calculations provide further information on the interaction of peroxynitrite with probe 3.

This mini-review summarizes the development of intracellular fluorogenic probes for biological investigations of hypochlorous acid/hypochlorite (HOCl/OCl

A series of copper(II) compounds 1-4 were synthesized and developed as fluorogenic probes to measure the cardiac marker homocysteine (Hcy) without any interference from other bioanalytes prevalent in human blood plasma including, cysteine and glutathione. UV-vis and EPR studies have provided confirmatory evidence for reduction-induced-emission-enhancement of the probe, which is responsible for the observed "off-to-on" behaviour towards Hcy. Water solubility, remarkable fluorescence enhancement (55-111 fold), and low detection ability (nearly 2.5 μM) make the probe suitable for clinical testing of cardiac samples. Investigation of 1 against a few reductive interferents testifies its specificity for Hcy. Results from clinical examination of cardiac samples by 1 when combined with the outcome of the reliability testing involving a clinically approved commercial immunoassay kit, validates the prospect of the molecular probe for direct measurement of Hcy in human plasma, which is unprecedented.

The development of receptors that can detect as well as treat cyanide ions in aqueous samples is indispensable for environmental protection. Herein, we present the bulk solvent-free and instant green synthesis of a series of turn-on fluorimetric probes that can specifically detect the deadly poison cyanide among various anions and metal ions in water. Selective recognition of cyanide by the mechanosynthesized compounds is even observable by the naked eyes, which remained unaffected in the presence of various challenging species. NMR spectroscopic investigation supports the chemodosimetric sensing of cyanide by the receptors. A remarkable 55-83 fold fluorescence enhancement by the probes enabled us to reach a limit of detection (LOD) in the range of 8-26 ppb, well below the permissible limit of cyanide in drinking water. Being minuscule soluble in water, cyanide treatment studies with the ionophores showed greater than 99% reduction in the free cyanide concentration after three consecutive cycles of operation. Furthermore, the compounds can be used as sensitive probes for the estimation of cyanide in human blood serum in physiological conditions. Overall, the results presented in this article will certainly find great use in the area of cyanide pollution with regard to simultaneous sensing and treatment of free cyanide, which is heretofore unprecedented.

Bio-convection is an important phenomenon which is described by hydrodynamic instability and pattern in suspension of biased swimming microorganisms. This hydrodynamics instability arises due to the coupling force between the motion of the micoorganisms and fluid flow. It becomes more significant when nanoparticles are immersed in the base fluid with non-Newtonian rheology. This study presents the bio-convection for a viscoelastic Casson nanofluid flow over a stretching sheet. The Cattaneo–Christov double diffusion, induced magnetic field, thermal radiation, heat generation, viscous dissipation and chemical reaction are taken into account. The boundary condition is enriched with the suction / injection and melting phenomena at the surface. Highly coupled nonlinear governing equations are simplified into a system of coupled ordinary differential equation by using proper similarity transformation. The spectral quasi-linearization method (SQLM) is used to solve the transformed governing equations numerically. Good agreement is observed with the numerical data investigated in the previous outstanding works. It is observed that the density of the motile microorganisms depends on Peclet number and bio-convective Lewis number. Bio-convection Rayleigh number increases the possibility of bio-convection in the system which results in the enhancement of temperature. It is also examined that temperature and concentration profiles increase with the Eckert number and thermophoresis parameter.

Singlet oxygen (

The chapter largely focuses on the application quality by design (QbD) on self-emulsifying drug delivery system (SEDDS). SEDDS, an isotropic mixture of lipid, surfactant, cosurfactant, and drug, is a promising technology to improve the bioavailability of poorly water-soluble drugs. The chapter is primarily sectioned into (a) application of Box-Behnken design in SEDDS, (b) application of central-composite design in SEDDS, (c) application of D-optimal design in SEDDS (d) application of full-factorial design in SEDD, and (e) application of simplex-lattice design in SEDDS, followed by an exhaustive table illustrating the application of QbD in SEDDS. The literature reviews on QbD on SEDDS unequivocally exemplify the wide acceptance of application of the statistical tool in the development of SEDDS.

The illumination characteristics of light sources can determine whether the light source is a normal or a faulty one. The proposed work is based on moving a platform containing a light source in both horizontal and vertical directions by gesture recognition. The gesture recognition done by Fuzzy C means and snake algorithm-based skin color detection makes the recognition more accurate. The illumination values of the light source are obtained by a webcam. The set of data helps in classification of the state of an unknown light source (normal or faulty) by support vector machines with radial basis function as kernel with a yield of an error rate of about 0.6% marking the efficacy of the system and making the system a novel and sophisticated one.