Selective Detection of Picric Acid by Benzodiazepine Containing Enaminone Core as Receptor and Its Application to Real Water Sample Analysis.

Nitroaromatic compounds are highly explosive and illegitimate substances. Over a decade, chemists have been affianced in extensive research on the selective and sensitive detection of these nitroaromatic explosives for homeland security and environmental protection. The benzodiazepine-based enaminone (BDE) receptor has been synthesized by aqueous extract of onion catalyzed three-component reaction between o-phenylenediamine, dimedone with an aldehyde.

5-Oxo-7,7-Dimethyl-5,6,7,8-Tetrahydro-4-H-Chromene Bearing N, N-Dimethylaniline as Turn-Off Fluorescent Chemosensor for Picric Acid in Real Water Sample.

We have synthesized a one-pot, three-component pyran-based fluorescence chemosensor using onion extract as a green catalyst. The confirmed structure of the 1:2 binding of receptor SPR-2-picric acid adduct revealed that the pyran-based receptor accommodated two guest picric acid molecules through non-covalent interactions. UV-Vis and fluorescence spectroscopy show high selectivity and sensitivity towards picric acid.

Hyaluronic Acid-Based Bioconjugate Systems, Scaffolds, and Their Therapeutic Potential.

In recent years, the development of hyaluronic acid or hyaluronan (HA) based scaffolds, medical devices, bioconjugate systems have expanded into a broad range of research and clinical applications. Research findings over the last two decades suggest that the abundance of HA in most mammalian tissues with distinctive biological roles and chemical simplicity for modifications have made it an attractive material with a rapidly growing global market. Besides its use as native forms, HA has received much interest on so-called "HA-bioconjugates" and "modified-HA systems".

Formulation, optimization and characterization of raloxifene hydrochloride loaded PLGA nanoparticles by using Taguchi design for breast cancer application.

Multidrug resistance in breast cancer and the associated side-effects of anticancer therapies are significant hurdles in chemotherapy-based treatment. Biodegradable polymeric nano-based targeted drug delivery technologies showed tremendous advantages in targeted local delivery with limited off-targeted side effects. Therefore, there is a persistent need to develop targeted nanomedicine systems for treatment of breast cancer.

Food and drug industry applications of microalgae Spirulina platensis: A review.

Spirulina platensis is a photosynthetic, blue-green, spiral- or bulb-shaped microalgae. Due to the presence of minerals, vitamins, pigments (carotenes, phycocyanin and chlorophyll) proteins (55%-70%), carbohydrates (15%-25%), and essential fatty acids (5%-8%), it has been used as a nutritional supplement for decades. NASA successfully employed it as a nutritional supplement for astronauts on space missions then its popularity was increased.

Transition metal-free approach for late-stage benzylic C(sp)-H etherifications and esterifications.

We report a transition metal-free approach for the regioselective functionalization of benzylic C(sp)-H bonds using alcohols and carboxylic acids as the nucleophiles. This straightforward and general route has provided various benzylic ethers and esters, including twelve pharmaceutically relevant compounds.

Quercetin conjugated fluorescent nitrogen-doped carbon dots for targeted cancer therapy application.

In this work, we report the development of nitrogen-doped carbon dots (NDCDs) as a drug carrier using quercetin (QC) as a model drug for anti-cancer drug delivery application. NDCDs were prepared by a simple hydrothermal method using as a carbon source. The characterization of QC-NDCDs was done by UV-vis spectroscopy, fluorescence spectroscopy, zeta potential measurements, high-resolution transmission electron microscopy (HR-TEM), Fourier transform infrared (FT-IR) spectroscopy, X-ray diffraction (XRD), and Raman spectroscopy.

Supramolecular self-assembly mediated aggregation-induced emission of fluorene-derived cyanostilbenes: multifunctional probes for live cell-imaging.

The first discovery of aggregation-induced emission (AIE), whereby luminogen aggregation plays a positive role in enhancing the light-emission efficiency, has piqued the interest of many researchers as it opens up a new avenue for the exploration of practically beneficial luminescent materials. Diverse AIE-active luminogens (or AIEgens) with tunable emission colours and very high quantum yields (up to unity) in the solid state have been extensively utilised in a broad range of fields including optoelectronics, energy and bioscience. In this article, we describe novel fluorene-based fluorogens that exhibit bright emission in the solid-state, mechanical stimuli-responsive optical properties and aggregation-induced emissive ability, and were able to modulate their donor and acceptor properties.

A Tunable Palette of Molecular Rotors Allows Multicolor, Ratiometric Fluorescence Imaging and Direct Mapping of Mitochondrial Heterogeneity.

Environment-sensitive molecular probes offer the potential for a comprehensive mapping of the complex cellular milieu. We present here a radically new strategy of multiplexing highly sensitive, spectrally tuned fluorescent dyes for sensing cellular microenvironment. To achieve this multicolor, ratiometric cellular imaging, we first developed a series of highly sensitive, tunable molecular rotors for mitochondrial imaging, with emission wavelengths spanning the visible spectrum.

A highly potential acyclic Schiff base fluorescent turn on sensor for Zn ions and colorimetric chemosensor for Zn, Cu and Co ions and its applicability in live cell imaging.

Herein, we report two acyclic Schiff base receptors CS-1 and CS-2 capable of being selective fluorescent turn on for Znions and colorimetric chemosensor for Zn, Cu, and Co ions by showing a colour change from colourless to yellow in 1:1 ratio of acetonitrile and HEPES buffer (1:1, v/v, pH 7.4) without the interference from other metal ions screened (Cd, Hg, Sn, Ni, Cr, Mn, Pb, Ba, Al, Ca, Mg, K and Na). The fluorescence turn on enhancement towards Zn ions is ascribed to PET blocking, suppression of -C=N- isomerisation, and the ESIPT process.

Design expert assisted formulation, characterization and optimization of microemulsion based solid lipid nanoparticles of repaglinide.

Repaglinide, a member of the meglitinide class of drugs, is a new anti-diabetic agent that is utilized as an oral hypoglycemic agent. Using glyceryl monostearate, cetyl palmitate, and tristearin as lipids and poloxamer 188 as a surfactant, repaglinide-loaded solid lipid nanoparticles were created. Solid lipid nanoparticles were prepared utilizing an o/w microemulsion technique, which included the lipids glyceryl monostearate and tristearin, as well as waxes such as cetyl palmitate and the surfactant poloxamer 188.

Novel Benzothiazole-Based Highly Selective Ratiometric Fluorescent Turn-On Sensors for Zn and Colorimetric Chemosensors for Zn, Cu, and Ni Ions.

Metal ions play a very important role in environmental as well as biological fields. The detection of specific metal ions at a minute level caught much attention, and hence, several probes are available in the literature. Even though benzothiazole-based molecules have a special place in the medicinal field, only very few chemosensors are reported based on this moiety.

Formulation and evaluation of thermosensitive flurbiprofen nano gel for the ocular delivery.

The contemporary research implicates the formulation and evaluation of a thermosensitive nano gelling method to improve solubility and ocular residence time of flurbiprofen. This study was carried out in two phases. In the first phase, an insolubility drug has been formulated in the form of a nanoparticulate system and evaluated for its characteristics.

Colorimetric and fluorescence sensing of Zn ion and its bio-imaging applications based on macrocyclic "tet a" derivative.

We report on the synthesis and characterization of trans N, N'-di-substituted macrocyclic "tet a" probe (L) for metal ion sensing. Both the colorimetric and fluorescent titration studies are performed with different metal ions. The results have suggested that the probe L is very selective and sensitive towards Zn ions with significant changes in color.

Phenothiazine-rhodamine-based colorimetric and fluorogenic 'turn-on' sensor for Zn and bioimaging studies in live cells.

A phenothiazine-rhodamine (PTRH) fluorescent dyad was synthesized and its ability to selectively sense Zn ions in solution and in in vitro cell lines was tested using various techniques. When compared with other competing metal ions, the PTRH probe showed the high selectivity for Zn ions that was supported by electronic and emission spectral analyses. The emission band at 528 nm for the PTRH probe indicated the ring closed form of PTRH, as for Zn ion binding to PTRH, the λ get shift to 608 nm was accompanied by a pale yellow to pink colour (under visible light) and green to pinkish red fluorescence emission (under UV light) due to ring opening of the spirolactam moiety in the PTRH ligand.

Effect of substitution on the excited state photophysical and spectral properties of boron difluoride curcumin complex dye and their derivatives: A time dependent-DFT study.

The optical, charge transport and electronic properties of boron difluoride curcumin (BFC) complex have been explored using the DFT (Density Functional Theory) method and B3LYP functional with the combination of 6-31 + G(d,p) as a basis set. The influence of substitution with various electron releasing and withdrawing groups on the above properties is analyzed and discussed in this work. The results reveal that the BFC complex on additional electron releasing substitution experiences redshifts in the optical transitions, and this is correlated with the dipole moment, NBO charges, HOMO-LUMO energy gap.

Turn-on Fluorescence Chemosensor for Zn Ion Using Salicylate Based Azo Derivatives and their Application in Cell-Bioimaging.

The synthesis and optical studies of salicylate based azo derivatives (DPSAD and IPSAD) are reported. The receptors act as a versatile fluorogenic chemosensor for Zn causing a selective enhancement of fluorescence over other competing cations. The complex formed between receptors and Zn are identified on the basis of absorption and fluorescence titration and further confirmed by ESI-MS.

Execution of julolidine based derivative as bifunctional chemosensor for Zn and Cu ions: Applications in bio-imaging and molecular logic gate.

A simple julolidine based chemosensor (JT) was designed and synthesized by single condensation step. JT displayed excellent selectivity and sensitivity with on-off responses towards Zn and Cu over other biologically relevant metal ions in aqueous media. Upon addition of Zn ions, JT exhibited a significant blue shift in emission followed by turn-on enhancement while with Cu, the fluorescence intensity of JT was completely vanished.

Coumarin based hydrazone as an ICT-based fluorescence chemosensor for the detection of Cu ions and the application in HeLa cells.

We have constructed a new coumarin based fluorescence probe BENZPYR with ICT character through condensation of N, N-diethylamino-3-acetyl coumarin with 2-hydrazinobenzothiazole. The absorbance and fluorescence spectral characteristics of BENZPYR revealed that the chemosensor can specifically detect for Cu ions over other different metal ions and the lowest limit of detection was found in nano molar range. The turn off sensor of BENZPYR is related to chelation enhanced quenching (CHEQ) and intramolecular charge transfer (ICT) processes were serve as excellent fluorescent detection of Cu ions in DMF medium.

A Fluorescent Turn-On Carbazole-Rhodanine Based Sensor for Detection of Ag Ions and Application in Ag Ions Imaging in Cancer Cells.

Carbazole - Rhodanine conjugate is an effective fluorescent host for silver ions through fluorometric transformation from green to red color with a hyperchromic emission. An intramolecular charge transfer process derived from carbazole towards rhodanine favors interaction of thiocarbonyl S and carboxylic acid O of the rhodanine moiety towards Ag ion. Carbazole - rhodanine dyad accomplishes the lowest detection limit of 12.

Pineapple Peel-Derived Carbon Dots: Applications as Sensor, Molecular Keypad Lock, and Memory Device.

Herein, the fluorescent carbon dots (CDs) with blue emission were prepared by hydrothermal treatment using pineapple peel as a source of carbon. The as-prepared CDs exhibited turn-Off fluorescence behavior toward Hg and subsequent turn-On behavior for l-cysteine along with enhanced biocompatibility and negligible cytotoxicity for cell imaging. The practical applicability of carbon dots was used for the quantification of Hg in water.

Anthracene-Based Highly Selective and Sensitive Fluorescent "" Chemodosimeter for Hg.

Three π-extended anthracene-bearing thioacetals () have been synthesized, and their fluorescence "" responses to Hg ions are studied. The chemodosimetric fluorescence-sensing behavior and their resulting hydrolysis via a desulfurization reaction mechanism leads to the formation of highly fluorescent respective aldehyde substitutions. Furthermore, this mechanism was supported by increase in the quantum yields of their resulting aldehydes and is correlated to their molecular substitution.

Bioresponsive drug delivery systems in intestinal inflammation: State-of-the-art and future perspectives.

Oral colon-specific delivery systems emerged as the main therapeutic cargos by making a significant impact in the field of modern medicine for local drug delivery in intestinal inflammation. The site-specific delivery of therapeutics (aminosalicylates, glucocorticoids, biologics) to the ulcerative mucus tissue can provide prominent advantages in mucosal healing (MH). Attaining gut mucosal healing and anti-fibrosis are main treatment outcomes in inflammatory bowel disease (IBD).

Selective and sensitive fluorescent sensor for Pd using coumarin 460 for real-time and biological applications.

The efficient fluorescent property of coumarin 460 (C460) is utilized to sense the Pd selectively and sensitively. Fabrication of a sensor strip using commercial adhesive tape is achieved and the detection of Pd is attempted using a handy UV torch. The naked eye detection in solution state using UV chamber is also attempted.