Green Sources Derived Carbon Dots for Multifaceted Applications.

For the past decade, the Carbon dots (CDs) a tiny sized carbon nanomaterial are typically much attentive due to their outstanding properties. Nature is a fortune of exciting starting materials that provides many inexpensive and renewable resources which have received the topmost attention of researchers because of non-hazardous and eco-friendly nature that can be used to prepare green CDs by top-down and bottom-up synthesis including hydrothermal carbonization, microwave synthesis, and pyrolysis due to its simple synthetic process, speedy reactions and clear-cut end steps. Compared to chemically derived CDs, green CDs are varied by their properties such as less toxicity, high water dispersibility, superior biocompatibility, good photostability, bright fluorescence, and ease of modification.

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.

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.

Carbazole-azine based fluorescence 'off-on' sensor for selective detection of Cu and its live cell imaging.

A new carbazole-azine based fluorescent sensor was synthesized and characterized. The selectivity of the sensor for Cu over other counter ions in a dimethyl sulfoxide/H O mixture was shown through enhancement in fluorescence - an off to on transformation. The specificity of the probe towards Cu was evident in ultraviolet/visible, fluorescence, Fourier transform infrared and mass studies.

Rhodamine Diaminomaleonitrile Conjugate as a Novel Colorimetric Fluorescent Sensor for Recognition of Cd Ion.

Rhodamine diaminomaleonitrile linked probe (RD-1) shows highly sensitive colorimetric and selective turn-on fluorescent response to Cd over other metal ions. The fluorescence intensity and absorbance of the probe RD-1 showed a good linearity, with very low detection limits of 18.5 nm.

Sensing and inhibition of amyloid-β based on the simple luminescent aptamer-ruthenium complex system.

Aggregation of amyloid-β (Aβ) peptide has been known to be pathologically associated with Alzheimer and dementia diseases. Amyloid-β fibrils serve as an important target for the drugs development and diagnosis of neurodegenerative diseases. Herein, we report a new [Ru(dmbpy)(dcbpy)dppz)] complex (dmbpy; 4,4'-dimethyl-2,2'-bipyridine, dcbpy; 4,4'-dicorboxy-2,2'-bipyridine, dppz; dipyridophenazine) intercalated aptamer based recognition of amyloid-β.

A selective, long-lived deep-red emissive ruthenium(II) polypyridine complexes for the detection of BSA.

A selective, label free luminescence sensor for bovine serum albumin (BSA) is investigated using ruthenium(II) complexes over the other proteins. Interaction between BSA and ruthenium(II) complexes has been studied using absorption, emission, excited state lifetime and circular dichroism (CD) spectral techniques. The luminescence intensity of ruthenium(II) complexes (I and II), has enhanced at 602 and 613 nm with a large hypsochromic shift of 18 and 5 nm respectively upon addition of BSA.

Sensitized near-infrared luminescence from Nd(III), Yb(III) and Er(III) complexes by energy-transfer from ruthenium 1,3-Bis([1,10]phenanthroline-[5,6-d]-imidazol-2 -yl)benzene.

The luminescent ruthenium 1,3 -bis([1,10]phenanthroline-[5,6 -d]- imidazol-2 -yl)benzene (bpibH2) complex, a potentially useful bridging ligand with a vacant diimine site, has been used as 'metallo ligand' to make heterodinuclear d-f complexes by attachment of a {Ln(dik)3} fragment (dik = 1,3-diketonate) at the vacant site. When Ln = Nd, Yb, or Er the lanthanide centre has low-energy f-f excited states capable of accepting energy from the (3)MLCT excited state of the Ru(II) centre, there is quenching in the (3)MLCT luminescence of the Ru(II) centre, that affords sensitized lanthanide(III) based luminescence in the near-IR region. Nd(III) was found to be the most effective at quenching the (3)MLCT luminescence of the ruthenium component because of the high density of f-f excited states of the appropriate energy which make it as effective energy-acceptor compared to Er and Yb complexes.