Lobelia trigona Roxb-based nanomedicine with enhanced biological applications: in vitro and in vivo approach.

This is the first study to report the green synthesis of Lobelia trigona Roxb-mediated silver nanoparticles (LTAgNPs). The optical and structural properties of the synthesised LTAgNPs were analysed using ultraviolet-visible spectroscopy, scanning electron microscopy, Fourier transform infrared, dynamic light scattering and energy dispersive X-ray. LTAgNps were evaluated for their anti-bacterial and anti-fungal properties against 18 pathogens and exhibited significant inhibition against all the strains tested. LTAgNPs had potential scavenging effects on the DPPH, •OH, O2•- free radical scavenging assays and reducing power assay. LTAgNps possess strong anti-cancer activity against five human cancer cell lines (A549, MCF-7, MDA-MB-231, HeLa and KB) in a dose-dependent manner. The antiproliferative, anti-inflammatory and genotoxicity effects of LTAgNPs were further confirmed by the lactate dehydrogenase release assay, nitric oxide inhibitory assay and comet assay. Furthermore, the incision, excision and burn wound-healing activity of formulated LTAgNPs ointment was assessed in rats. All the wounds had significant healing in groups treated with LTAgNPs ointment compared to the groups treated with the commonly prescribed ointment (SilverexTM). This study shows and suggests that the previously unreported LTAgNPs could be used as a nanomedicine with significant biological applications.

Unusual Fluorescence Quenching-Based Al3+ Sensing by an Imidazolylpiperazine Derivative. ß-Cyclodextrin Encapsulation-Assisted Augmented Sensing.

We report in this paper an unusual ß-cyclodextrin mediated-aluminum (III) ion sensing based on augmented quenching of fluorescence. The fluorescent sensing of metal ions by a new ligand prepared (L = 4-[{4-(1H-imidazol-1-yl)phenyl]imino}methyl]piperazine-1-carboxaldehyde) has been investigated as well as the effect of the supramolecular complex formation with ß-CD. In aqueous solution, L shows an increase of fluorescence due to the interaction with ß-cyclodextrin with a formation constant of 77 (± 12) M-1. The ROESY NMR spectrum clearly indicates that L is encapsulated by ß-CD. Theoretical calculations show the possible structure both of the L-ß-CD adduct and of the coordination mode of Al3+ ion to L. In the presence of ß-CD, the piperazine adopts a distorted conformation. It leads to an enhanced Al3+ sensing by the compound in its supramolecular complexed form. The lower limit of detection of Al3+ ions is 6.00 × 10-8 mol L-1. This detection limit slightly expands for L in the presence of ß-CD.

Electron-deficient tripodal amide based receptor: An exclusive turn-on fluorescent and colorimetric chemo sensor for cyanide ion.

Here in, we have designed, synthesized and isolated sensor L, as an exclusive selective turn-on fluorescent chemo sensor for cyanide ion. The acetonitrile solution contains L with tetrabutyl ammonium cyanide, results sudden color change from colorless to yellowish-brown. Chemosensor L produced a strong fluorescence response with an enhancement of very high fluorescence intensity while addition of CN- ion and the strength of the chemosensor L towards cyanide binding is found to be 3.9813×104M-1. In order to use this sensor in practical application, we also prepared a cassette which is fabricated with sensor L and we succeeded to sense cyanide ion.

A new fluorescent chemosensor for cadmium(II) based on a pyrene-appended piperidone derivative and its ß-cyclodextrin complex.

We report, in this article, a piperidin-4-one derivative carrying pyrenyl fluorescent reporter groups which acts as a Cd2+ ion sensor. The compound is synthesized and characterized using IR and NMR spectral techniques. The compound forms an inclusion complex with ß-cyclodextrin. It selectively binds to Cd2+ ions in water and aqueous ß-cyclodextrin media. The stoichiometry of the host-guest complex of the compound with ß-cyclodextrin is 1:2. The ligand-metal ion binding stoichiometry is 1:1 both in water and in ß-cyclodextrin. The linear concentration range of detection of the metal ion is reported. Cyclodextrin complex formation does not affect the metal ion selectivity of the compound.

A simply synthesized biphenyl substituted piperidin-4-one for the fluorescence chemosensing of Cd2.

Ion-induced change in fluorescence is a straight-forward method for detection of toxic metal ions showing immediate response. Cadmium ions are toxic to the environment. We report in this paper a piperidine-4-one-based fluorescent chemosensor of Cd2+ ions, designed and synthesized by a simple method. The compound is characterized using infra-red (IR) and 1 H-NMR spectral techniques. The chemosensor showed Cd2+ ion selectivity and sensitivity in aqueous solution. The stoichiometry and the binding constants were determined using fluorescence spectroscopy. Piperidine-4-one shows a 1:1 stoichiometric binding to Cd2+ . The limit of detection of Cd2+ was reported.