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Hypoxia-induced intratumoral heterogeneity poses a major challenge in tumor therapy due to the varying susceptibility to chemotherapy. Moreover, the spatial distribution patterns of hypoxic and normoxic tissues makes conventional combination therapy less effective. In this study, a tumor-acidity and bioorthogonal chemistry mediated in situ size transformable nanocarrier (NP@DOX

The present study involves the adsorption of hexavalent Chromium(Cr(VI)) using chitosan grafted graphene oxide (CS-GO) nanocomposite in batch mode. The CS-GO nanocomposite material was prepared by ultrasonic irradiation technique. The CS-GO adsorbent was characterized by X-ray diffraction (XRD), Fourier transform infrared (FTIR) spectroscopy, scanning electron microscopy (SEM) and Tunnelling electron microscopy (TEM), followed by Cr(VI) adsorption studies. The adsorption capacity of 104.16 mg/g was achieved at pH 2.0, in the contact time of 420 min. The adsorption process was described by the pseudo second order kinetic and Langmuir isotherm model. The nano-microstructural investigation validates the successful adsorption of Cr(VI) on CS-GO nanocomposite. The CS-GO material is recyclable up to 10 cycles with the minimum loss in adsorption capacity.

A magnetically modified graphene oxide/chitosan/ferrite (GCF) nanocomposite material was synthesized and exploited for removal of Chromium(VI) from aqueous solution. The GCF nanocomposite material was characterized by powder-X-ray diffraction (powder-XRD), Fourier transform infrared spectroscopy (FT-IR), scanning electron microscope- energy dispersive X-ray (SEM-EDX) analysis, transmission electron microscopy (TEM) thermogravimetric analysis (TGA), UV–vis diffusive reflectance spectra and Brunauer–Emmett–Teller (BET) analysis. The effect of pH, adsorbent dose, contact time and initial Cr(VI) metal ion concentration were studied in batch process. The GCF nanocomposite material showed an adsorption capacity of 270.27 mg g−1 for Cr(VI) at pH 2.0. The adsorption mechanism of GCF adsorbent material was well described by Langmuir isotherm and pseudo second order kinetic model, with a high regression coefficient (

In the present study, a novel nanocomposite adsorbent material was synthesized using chitosan (CS), graphene oxide (GO) and metal organic framework (MOF [Zn(BDC)(DMF)]) for the adsorption of Chromium (VI) heavy metal from aqueous solution. The characterization of the prepared GO-CS@MOF [Zn(BDC)(DMF)] was accomplished by powder X-ray diffraction (PXRD), Fourier transform infrared (FT-IR) spectroscopy, scanning electron microscopy (SEM) and Brunauer–Emmett–Teller (BET), followed by Cr(VI) adsorption-desorption studies. Experimental parameters such as effect of pH, temperature, contact time, adsorbent dosage and shaking speed were optimized. The GO-CS@MOF [Zn(BDC)(DMF)] showed an adsorption capacity of 144.92 mg/g for Cr(VI) at pH 3.0. Thermodynamic properties (ΔGo, ΔHo, ΔSo) have been calculated and the process is found to be endothermic, favourable and spontaneous. The adsorption study of Cr(VI) by GO-CS@MOF [Zn(BDC)(DMF)] comprises both kinetic and isotherm studies. The equilibrium adsorption followed Langmuir model and adsorption reaction was found to be pseudo-second order confirming chemisorption. The developed GO-CS@MOF [Zn(BDC)(DMF)] nanocomposite material will serve as a new type of platform for removing Cr(VI) from wastewater.

Pseudohalides are well known to do similar chemistry like halides. Thiocyanate, a pseudohalide acts like halides in many ways. Thiocyanate radicals ( SCN) are generated from readily available thiocyanate salts using Rose Bengal through single electron transfer (SET) in the presence of visible light. Thiocyanate radicals abstract hydrogen like other halide radicals, so this aspect of chemistry was used for the oxidation of alcohols to their corresponding aldehydes using oxygen as the terminal oxidant. This method shows a broad scope and well tolerance towards various functional groups.

The early stage detection, diagnosis and treatment of prostate cancer are life-saving events in patients housing potentially invasive disease. The healthy human prostate accumulates the maximum amount of zinc compared to any soft tissue in the body. But in the contrary, an inability of cancer cells to accumulate zinc has been found with the development of malignancy resulting in a dramatic reduction in the zinc content of prostate tissue. In this current study, we designed and developed a dipicolylamine-coumarin-chlorambucil (Dpa-Cm-Cmbl) based system which can act as a sensor (for the prostatic zinc i.e. diagnosis) as well as photoresponsive drug delivery system (treatment). We demonstrated that Dpa-Cm-Cmbl being a single component system, first guided us to locate the diseased area by using cellular zinc concentration as a biomarker and in the next there was on-demand release of anticancer drug chlorambucil by employing the external stimulus light. In-vitro studies showed that Dpa-Cm-Cmbl presents excellent properties like detection of cancerous regions in the prostate, photoregulated drug delivery in controlled manner, biocompatibility and all together an efficient chemotherapy.

New, simple and inexpensive receptors based on coumarin-thiocarbohydrazone (CTC) and coumarin-carbohydrazone (CC) were synthesized for fluoride ion in CH 3 CN/DMSO. Receptor CTC showed specific selectivity and sensitivity toward fluoride giving rise to an ON 1 –OFF–ON 2 fluorescent response and visual colorimetric change. The recognition mechanism was investigated using UV–vis, fluorescence spectroscopy, and 1 H NMR titration experiments. The Job's plot analysis and Benesi–Hildebrand equation revealed that the binding between the CTC or CC with F − is in 1:1 stoichiometry. Formation of such 1:1 complex led to the quenching of green fluorescence of CTC and upon excess addition of F − , the [CTC–F − ] complex underwent an intracomplex proton transfer from N H fragment of the host (CTC) to the anion producing a distinctly emissive (cyan colored fluorescence) receptor [CTC] 2− .

Irradiation of azido carbonyl compounds using UV light (⩾310 nm) produced triplet alkyl nitrenes and aroyl radicals, which resulted in efficient cleavage of single strand DNA at pH 7.0. DNA cleaving ability of azido carbonyl compounds was found to be dependent on its concentration and substituents on its aromatic ring. Further, newly synthesized naphthalene based azido carbonyl compounds showed DNA cleavage ability at longer wavelength of UV light (⩾350 nm) and also binding studies revealed that they bind to ct-DNA by weak intercalation mode.

Simple and efficient photoacid generators (PAGs) for carboxylic and sulfonic acids based on N-acyl-N-phenylhydroxylamines have been demonstrated. Irradiation of o-carboxylates and thermally rearranged o-arenesulfonates of N-acyl-N-phenylhydroxylamines using UV light (≥254 nm) in aqueous methanolic solution resulted in efficient generation of carboxylic and sulfonic acids, respectively. The carboxylic acid generation ability of N-acyl-N-phenylhydroxylamines was found to be dependent on their N-acyl substituents. Further, polymer bearing o-arenesulfonates of N-acyl-N-phenylhydroxylamine was synthesized and demonstrated as PAG for sulfonic acids.

A series of new fluorescent ester conjugates of carboxylic acids including amino acids was synthesized by coupling with an environment-sensitive fluorophore 1-acetylpyrene. Interestingly, the fluorescence properties of the ester conjugates and 1-acetylpyrene were found to be highly sensitive to its surrounding environment. The results obtained from the photolysis of the ester conjugates indicated that various factors like solvent, irradiation wavelength, and the structure of the conjugates govern the rate of the photocleavage.

Photoinduced homolytic fission of nitrogen–oxygen bond in N , O -diacyl-4-benzoyl- N -phenylhydroxylamines using ⩾310 nm UV light for 10 min produced acylaminyl and acyloxy radicals, which resulted in single strand cleavage of DNA at pH 7.0. Further the DNA cleaving ability of N , O -diacyl-4-benzoyl- N -phenylhydroxylamines found to depend both on its concentration and acyl substituents.

Partially Fe filled multi-walled carbon nanotubes (MWCNTs) were grown by chemical vapor deposition with propane at 850 {\deg}C using a simple mixture of iron (III) acetylacetonate (Fe(acac)3) powder and conventional photoresist. Scanning electron microscopy revealed that catalytic nanoparticles with an average diameter of 70 nm are formed on the Si substrate which governs the diameter of the MWCNTs. Transmission electron microscopy shows that the nanotubes have a multi-walled structure with partial Fe filling. A site-selective growth of partially Fe filled MWCNTs is achieved by a simple photolithographic route., Comment: Filled CNT, CVD, Partial filling, Photolithography

The antifeedant activity of six diterpenes against the fourth instar nymphs and adults of Henosepilachna vigntioctopunctata was evaluated using a dual choice leaf disc bioassay. Caryoptin was the most effective antifeedant among the compounds tested. Andrographolide, wightionolide and 3-epicaryoptin did not deter feeding by adults. The possible relationship of structure to antifeedant activity is discussed.

Tetranortriterpenoids from Azadirachta indica A. Juss and Soymida febrifuga (Meliaceae), have been selectively oxidized to single major products which exhibit bioactivity higher than the parent compounds, comparable to that of azadirachtin A. The reaction proceeds to completion in less than 15 min and 1 min on being assisted by ultrasound and microwave irradiation, respectively.