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A coumarin-based fluorogenic probe, PCO-1, senses carbon monoxide (CO) selectively in HEPES buffer at pH 8.0 through the intramolecular cyclization-elimination pathway based on Pd(0) mediated reaction. The probe exhibits a 'turn-on' response of CO over a variety of relevant reactive oxygen, nitrogen and sulfur species.

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Model lipid vesicles (LAPC) self-reproduce to generate unilamellar daughter vesicles in the presence of a cell-penetrating peptide (R9) due to a loss of the bilayer rigidity.

Two sets of new mononuclear cyclometalated complexes of the types [MIII(ppy)2(L)] (Ir1 and Rh1) and [MIII(bzq)2(L)] (Ir2 and Rh2) [where M = Rh/Ir; L = N-(furan-2-ylmethyl)-2-pyridinecarboxamide; ppy = 2-phenylpyridine (1); bzq = benzo­[h]­quinoline (2)] are presented to understand the significant differences of emission behaviors between Ir­(III) and Rh­(III) complexes. The complexes were fully characterized by using physicochemical and spectroscopic tools along with the detailed structural studies of Ir1 and Rh2 by single-crystal X-ray diffraction. Structural analyses showed that in both complexes the metal exhibits a distorted octahedral geometry. The geometries, electronic structures, lowest-lying singlet–singlet absorptions, vertical singlet–triplet excitation, and triplet–singlet emission behaviors of all the complexes (Ir1–2 and Rh1–2) were examined by means of DFT and TDDFT approaches. In order to find out the considerable differences in experimentally observed emission properties of Ir­(III) (5d6) and Rh­(III) (4d6) complexes, the radiative and nonradiative processes were calculated and compared quantitatively and somewhat qualitatively. The results indicate that the smallest S1–T1 splitting energy (ΔE S1-T1), large transition dipole moment (μS1), and reverse order of energy states between the triplet metal-to-ligand charge transfer (3MLCT) and triplet metal-centered (3MC) states were responsible for the higher radiative process of Ir­(III) complexes than those of Rh­(III) complexes. Since the nonradiative decay process plays an important role in the photodeactivation process, the potential energy profile for the deactivation process from 3MLCT via 3MC was explored. In addition to the relative energies of 3MLCT and 3MC states, the position of minimum energy 3MC/1GS crossing point (MECP) was also computed.

Franconibacter pulveris strain DJ34, isolated from Duliajan oil fields, Assam, was characterized in terms of its taxonomic, metabolic and genomic properties. The bacterium showed utilization of diverse petroleum hydrocarbons and electron acceptors, metal resistance, and biosurfactant production. The genome (4,856,096bp) of this strain contained different genes related to the degradation of various petroleum hydrocarbons, metal transport and resistance, dissimilatory nitrate, nitrite and sulfite reduction, chemotaxy, biosurfactant synthesis, etc. Genomic comparison with other Franconibacter spp. revealed higher abundance of genes for cell motility, lipid transport and metabolism, transcription and translation in DJ34 genome. Detailed COG analysis provides deeper insights into the genomic potential of this organism for degradation and survival in oil-contaminated complex habitat. This is the first report on ecophysiology and genomic inventory of Franconibacter sp. inhabiting crude oil rich environment, which might be useful for designing the strategy for bioremediation of oil contaminated environment.

A naphthalimide-based fluorescence light-up probe, FCP-Pd, has been designed and synthesized for selective detection and quantitation of creatinine in PBS buffer of pH 7.2 at 37 °C with a 'turn-on' response over a variety of interfering metal ions and/or anions and several biologically significant species. This probe is highly effective in estimating creatinine in human blood serum, which confirms the reliability and accuracy of this new system to be applied in clinical and toxicological analysis.

Copper(II) and copper(I) complexes of a newly designed and crystallographically characterized Schiff base (HL) derived from rhodamine hydrazide and cinnamaldehyde were isolated in pure form formulated as [Cu(L)(NO3)] (L-Cu) (1) and [Cu(HL)(CH3CN)(H2O)]ClO4 (HL-Cu) (2), and characterized by physicochemical and spectroscopic tools. Interestingly, complex 1 but not 2 offers red fluorescence in solution state, and eventually HL behaves as a Cu(II) ions selective FRET based fluorosensor in HEPES buffer (1 mM, acetonitrile-water: 1/5, v/v) at 25 °C at biological pH with almost no interference of other competitive ions. The dependency of the FRET process on the +2 oxidation state of copper has been nicely supported by exhaustive experimental studies comprising electronic, fluorimetric, NMR titration, and theoretical calculations. The sensing ability of HL has been evaluated by the LOD value towards Cu(II) ions (83.7 nM) and short responsive time (5-10 s). Even the discrimination of copper(I) and copper(II) has also been done using only UV-Vis spectroscopic study. The efficacy of this bio-friendly probe has been determined by employing HL to detect the intercellular distribution of Cu(II) ions in HeLa cells by developing image under fluorescence microscope.