A Visual and Ratiometric Chemosensor Using Thiophene Functionalized Hydrazone for the Selective Sensing of Pb2+ and F- Ions.

Herein, a simple, efficient ratiometric chemosensor was reported for the selective sensing of Pb2+ and F- ions using thiophene functionalized hydrazone as a chemical probe. Hydrazone moiety was developed by utilizing thiophene/naphthalene as a platform for the particular recognition of cation and anion. The structures of the precursor (Z)-(1-(5-bromothiophen-2-yl)ethylidene)hydrazine (ABTH) and the final probe 1-((Z)-(((Z)-1-(5-bromothiophen-2-yl)ethylidene)hydrazono)methyl)naphthalen-2-ol (NAPABTH) were confirmed by 1H, 13C-NMR and LC-MS spectroscopic methods. The interaction of NAPABTH with Pb2+ and F- ions was visually observed by the formation of pink and dark yellow solutions, respectively. The detection limits were found to be very low for Pb2+ as 1.06 ppm and for F- ions as 3.72 nM. This visual detection of Pb2+/F- ions with satisfactory outcomes obtained from UV-Vis titrations. The sensing mechanistic pathways and stoichiometric ratios were obtained from DFT and Job's plot, respectively. The observed results are highly promising as highly selective chemosensor with lower detection limits for Pb2+ and F- ions. This strategy could exhibit tremendous applications for the selective sensing of heavy metal cations with rapid sensitivity for the design of new devices.

Retinal photoreceptors targeting SA-g-AA coated multilamellar liposomes carrier system for cytotoxicity and cellular uptake evaluation.

Here, the retinal targeting SA-g-AA coated multilamellar liposomes carrier synthesized to deliver the bioactive agents into the retinal region of the eye. The multilayered targeting macromolecules of liposomes prepared using a layer-by-layer assembly. The curcumin (CUR) and Rhodamine B (RhB) dyes loaded in a multilamellar vesicle (MLV) were synthesised by the lipid film hydration method. The sodium alginate grafted acrylic acid (SA-g-AA) conjugated with riboflavin (RB) was coated over MLV by O/W emulsion method followed by ionotropic gelation. FT-IR and 1H NMR spectroscopy techniques used to analyse the structural features of the MLV-SA-g-AA-RB. The results of DLS and TEM revealed that the carrier could be of uniform spheres, with a low polydispersity index, and outstanding performance in phrases of dye encapsulation and extended-release ability. An MTT assay investigated cell viability against Fibroblast WS1, and human embryonic stem cells-derived retinal pigment epithelial cells (hESC-RPE) implied that the carrier is of excellent biocompatibility. Retina targeting nature of the system confirmed via cellular uptake results revealed that the increases the dye concentration in the cells. Overall, the outcomes suggested that carriers could lead to the improvement of a feasible two photoreceptors targeting drug carriers, and it has the potential to deliver the multidrug in the retinal region of the eye.

Combined photodynamic-chemotherapy investigation of cancer cells using carbon quantum dot-based drug carrier system.

The combined chemotherapy and photodynamic therapy have significant advantages for cancer treatments, which have higher therapeutic effects compared with other medicines. Herein, we focused on the synthesis of carbon quantum dot (CQD) based nanocarrier system. CQD and 5-aminolevulinic acid (5-ALA) were conjugated with mono-(5-BOC-protected-glutamine-6-deoxy) ß-cyclodextrin (CQD-Glu-ß-CD) moiety, and finally, the anticancer chemotherapy doxorubicin (DOX) drug was loaded in the 5-ALA-CQD-Glu-ß-CD system. The stepwise physicochemical changes for the preparation of the DOX loaded 5-ALA-CQD-Glu-ß-CD system were investigated by Fourier transform infrared (FT-IR) spectroscopy, X-ray diffraction (XRD), transmission electron microscopy (TEM), atomic force microscopy (AFM), and Raman fluorescence spectroscopy. The encapsulation efficiency of DOX in 5-ALA-CQD-Glu-ß-CD was observed at ∼83.0%, and the loading capacity of DOX is ∼20.37%. The in vitro releasing of DOX and 5-ALA was observed through the UV-vis spectroscopy by the λmax value of 487 nm and 253 nm, respectively. By the investigation against the breast MCF-7 cancer cells, the high cytotoxicity and morphological changes of cancer cells were observed by the treating of DOX/5-ALA-CQD-Glu-ß-CD. The generation of reactive oxygen species (ROS) upon 635 nm (25 mW cm-2) for 15 min laser irradiation-induced improved the therapeutic effects. In vitro cellular uptake studies recommend the synthesized DOX/5-ALA-CQD-Glu-ß-CD nanocarrier could significantly enhance the cell apoptosis and assist in the MCF-7 cell damages. The result suggests a multifunctional therapeutic system for chemo/photodynamic synergistic effects on cancer therapy.

Hydrazone Based Dual - Responsive Colorimetric and Ratiometric Chemosensor for the Detection of Cu2+/F- Ions: DNA Tracking, Practical Performance in Environmental Samples and Tooth Paste.

Colorimetric sensors have attracted wide scope of attentions due to its fascinating advantages, like handy, equipment-free and naked eye detections. In this investigation, a new and novel hydrazone based dual-responsive ratiometric/colorimetric chemosensor have been developed for highly selective and sensitive detection of Cu2+ and F- ions in dimethyl sulfoxide (DMSO) solvent. The probe showed highly selective sensing towards Cu2+ and F- ions by exhibiting a color change from pale yellow to yellowish green and pale yellow to yellowish brown respectively., in DMSO without any interference of other ions at same concentration. These experimental results have also substantiated by the NMR, HR-MS, UV-Vis spectroscopic, cyclic voltammetry, differential pulse voltammetry techniques and DFT calculations. The detection limits are found to be 5.8 µM for Cu2+ and 0.025 µM for F- ions which is far below to the values recommended by WHO. The stoichiometric ratios between NAPCBH and Cu2+/ F- ions were confirmed from the Job's plots and 1H NMR titration experiments which are found to be 2:1 and 1:1 respectively. The tracking ability of the DNA with NAPCBH-Cu2+ was studied by UV-Vis titration and Cyclic voltammetry measurements. It shows efficient affinity towards DNA with NAPCBH-Cu2+. The probe can also quantitatively determine the Copper and fluoride ions present in environmental samples & toothpaste. The NAPCBH was promptly recovered by utilizing very low concentration of HCl, showing that was found feasible and re-usable sensor for the convenient detection of Cu2+ and F- ions. Graphical Abstract.

Folate receptor targeted delivery of paclitaxel to breast cancer cells via folic acid conjugated graphene oxide grafted methyl acrylate nanocarrier.

The adaptability, joint with a large surface area, electronic flexibility, high intrinsic mobility, high mechanical strength and supreme thermal conductivity have condensed graphene family materials attractive as technological tools of the drug delivery system. In this present study, investigate a modified graphene oxide-methyl acrylate (GO-g-MA) nanocarrier for targeted anti-cancer drug delivery in breast cancer cells and the GO-g-MA fascinated with folic acidas a targeting ligand to target the cancer cells. Paclitaxel (PTX) was assembled through π-π stacking, hydrophophic interaction on the surface of the GO-g-MA/FA carrier. Structural modification of GO-g-MA, functionalization of targeting ligands GO-g-MA/FA and drug loaded GO-g-MA/FA-PTX was characterized and confirmed through FTIR, XRD, SEM,TEM and AFM analysis. The in-vitro drug release pattern of PTX from the GO-g-MA/FA was examined in different pH ranges. An MTT assay was performed to evaluate the cytotoxicity behaviour of the carrier and PTX loaded nanocarrier in the human breast cancer cell line (MDA-MB-231). GO-g-MA/FA-PTX carrier showed that 39% of cytotoxic effect. Furthermore, the in-vivo (DMBA induced breast cancer rats) studies were carried out and treatment with PTX- loaded GO-g-MA/FA nanocarrier attenuates the levels of mitochondrial citric acids enzymes to near normal.

Evaluation of DNA Binding, Cleavage, and Cytotoxic Activity of Cu(II), Co(II), and Ni(II) Schiff Base Complexes of 1-Phenylindoline-2,3-dione with Isonicotinohydrazide.

One new series of Cu(II), Co(II), and Ni(II) Schiff base complexes was prepared through the condensation reaction between 1-phenylindoline-2,3-dione with isonicotinohydrazide followed by metalation, respectively. The Schiff base ligand(L), (E)-N'-(2-oxo-1-phenylindolin-3-lidene)isonicotinohydrazide, and its complexes were found soluble in DMF and DMSO solvents and characterized by using the modern analytical and spectral techniques such as elemental analysis, conductivity, magnetic moments, IR, NMR, UV-visible, Mass, CV, and EPR. The elemental analysis data of ligand and their complexes were well agreed with their calculated values in which metal and ligand stoichiometry ratio 1 : 2 was noted. Molar conductance values indicated that all the complexes were found to be nonelectrolytes. All the complexes showed octahedral geometry around the central metal ions. Herein, we better characterized DNA binding with the complexes by UV-visible and CD spectroscopy and cyclic voltammetry techniques. The DNA cleavage experiments were carried out by Agarose gel electrophoresis method and the cytotoxicity experiments by MTT assay method. Based on the DNA binding, cleavage, and cytotoxicity studies, Cu and Ni complexes were found to be good anticancer agents against AGS-human gastric cancer cell line.

Antiplasmodial activity of two marine polyherbal preparations from Chaetomorpha antennina and Aegiceras corniculatum against Plasmodium falciparum.

The ocean covers more than 70% of earth surface and hosts most 300,000 described species of plants and animals to use, which have been virtually unexploited for the development of medicines. Marine plants are the good source of biologically active entities which exhibit therapeutic properties, when applied single or in combination of different plant extracts (polyherbal). Polyherbal preparations are always a complex mixture of different forms and thus different compounds, which might act as agonistic, synergistic, complementary, antagonistic or toxic way. The present study was initially carried out to test the antiplasmodial activity of 13 mangrove plants and eight seaweeds species distributed along the coast of south India. Of these, mangrove species Aegiceras corniculatum and the seaweed species Chaetomorpha antennina have shown maximum antiplasmodial activity. Hence, the present study was mooted out to increase the percentage of antiplasmodial activity when applied as polyherbal preparations. The effect of marine polyherbal preparations from the methanolic extracts of two marine plants A. corniculatum and C. antennina for their antiplasmodial activity was tested. It shows that the polyherbal extract showed 63.50 ± 0.408% suppression of parasitaemia against Plasmodium falciparum at 1.5 mg ml⁻¹ concentration. In vivo test was carried out with rat animal model to find out the effectiveness of the polyherbal extracts in the live system, which reveals that polyherbal extracts have exhibited remarkable antiplasmodial activity (50.57 ± 0.465%) against Plasmodium berghei at 120 mg kg⁻¹ bw. This study shows that combinations of mangrove plants and seaweeds extracts had a source of lead compounds for the development of new drugs for the treatment of malaria.

Mangrove plants as a source of lead compounds for the development of new antiplasmodial drugs from South East coast of India.

Malaria is the world's leading killer among the infectious diseases. The treatment of malaria is mystified by the challenges of widespread resistance of the malaria parasites to cheap and affordable antimalarial drugs. The present study was made in an attempt to identify the in vitro antiplasmodial activity against mangrove plant parts. (Avicennia marina, Acanthus ilicifolius, Bruguiera cylindrica, Excoecaria agallocha, Rhizophora apiculata, and Rhizophora mucronata mangrove plant extracts exhibited in vitro antiplasmodial activity against Plasmodium falciparum). Of the selected mangrove plant parts, the bark extract of A. marina exhibited minimum concentration of inhibitory activities IC(50) 49.63 µg.ml(-1). The leaf extract of A. marina, the hypocotyl extract of B. cylindrica, the leaf extract of E. agallocha, the flower extract of R. mucronata, and the hypocotyl extract of R. apiculata showed IC(50) values between 50 and 100 µg.ml(-1). Statistical analysis reveals that significant antiplasmodial activity (P<0.05) was observed between the concentrations and time of exposure. The chemical injury to erythrocytes was also carried out, and it shows that there were no morphological changes in erythrocytes by the ethanolic extract of mangrove plants after 48 h of incubation. The in vitro antiplasmodial activity might be due to the presence of alkaloids, carboxylic acids, coumarins, saponins, flavonoids, xanthoproteins, tannins, phenols, sugars, resins, steroids, and proteins in the ethanolic extracts of mangrove plants. It is concluded from the present study that the ethanolic extracts of mangrove plant parts of A. marina possess lead compounds for the development of antiplasmodial drugs.