00896nas a2200193 4500008004100000245008100041210006900122260000800191300001400199490000700213520024200220100001800462700002400480700002600504700002400530700002300554700001700577856010800594 2011 eng d00aReceptor design and extraction of inorganic fluoride ion from aqueous medium0 aReceptor design and extraction of inorganic fluoride ion from aq cMAY a7398-74000 v473 a

A receptor with acidic methylene hydrogens is found to act as an efficient binding mode for F−. This reagent could as well be used for selective and quantitative extraction of F− from the aqueous solution of NaF and sea water.

1 aDas, Priyadip1 aMandal, Amal, Kumar1 aKesharwani, Manoj, K.1 aSuresh, Eringathodi1 aGanguly, Bishwajit1 aDas, Amitava uhttps://library.ncl.res.in/content/receptor-design-and-extraction-inorganic-fluoride-ion-aqueous-medium01765nas a2200229 4500008004100000245009600041210006900137260000800206300001600214490000700230520098300237100002201220700001701242700001501259700001901274700002801293700002701321700002601348700002301374700001701397856012101414 2012 eng d00aRatiometric detection of Cr3+ and Hg2+ by a naphthalimide-rhodamine based fluorescent probe0 aRatiometric detection of Cr3 and Hg2 by a naphthalimiderhodamine cJAN a1769–17770 v513 a

Newly synthesized rhodamine derivatives, L1 and L2, are found to bind specifically to Hg2+ or Cr3+ in presence of large excess of other competing ions with associated changes in their optical and fluorescence spectral behavior. These spectral changes are significant enough in the visible region of the spectrum and thus, allow the visual detection. For L1, the detection limit is even lower than the permissible [Cr3+] or [Hg2+] in drinking water as per standard U.S. EPA norms; while the receptor, L2 could be used as a ratiometric sensor for detection of Cr3+ and Hg2+ based on the resonance energy transfer (RET) process involving the donor naphthalimide and the acceptor Cr3+/Hg2+-bound xanthene fragment. Studies reveal that these two reagents could be used for recognition and sensing of Hg2+/Cr3+. Further, confocal laser microscopic studies confirmed that the reagent L2 could also be used as an imaging probe for detection of uptake of these ions in A431 cells.

1 aMahato, Prasenjit1 aSaha, Sukdeb1 aSuresh, E.1 aDi Liddo, Rosa1 aParnigotto, Pier, Paolo1 aConconi, Maria, Teresa1 aKesharwani, Manoj, K.1 aGanguly, Bishwajit1 aDas, Amitava uhttps://library.ncl.res.in/content/ratiometric-detection-cr3-and-hg2-naphthalimide-rhodamine-based-fluorescent-probe02505nas a2200205 4500008004100000022001400041245016500055210006900220260007100289300001600360490000700376520165600383100001802039700002802057700002102085700002302106700002302129700001702152856013002169 2013 eng d a0020-166900aRole of metal ion in specific recognition of pyrophosphate ion under physiological conditions and hydrolysis of the phosphoester linkage by alkaline phosphatase0 aRole of metal ion in specific recognition of pyrophosphate ion u a1155 16TH ST, NW, WASHINGTON, DC 20036 USAbAMER CHEMICAL SOCcOCT a11034-110410 v523 a

Complexes synthesized from Zn(II), Cu(II), and Cd(II), using a dipicolyl amine derivative (L), showed unique specificity toward pyrophosphate ion (PPi or P4O74-) among all other common anionic analytes, including different biologically significant phosphate ion (PO43-, H2PO42-) or phosphate-ion-based nucleotides, such as AMP, ADP, ATP, and CTP. However, the relative affinities of PPi toward these three metal complexes were found to vary and follow the order K-a(L.Zn-PPi) > are given in units of (L.Cu-PPi)(a) >= K-a(L.Cd-PPi). Luminescence responses of the receptor L were substantial on binding to Zn2+ and Cd2+, while relatively a much smaller luminescence response was observed in the presence of Cu2+. Luminescence responses of L.M-PPi (M is Zn2+, Cd2+, and Cu2+) were further modified on binding to the PPi ion. This could be utilized for quantitative detection of PPi in physiological condition as well as for developing a real time ``turn-on'' (for L.Zn and L.Cu) and ``turn-off'' (for L.Cd) fluorescence assay for evaluating the enzymatic activity of alkaline phosphatase (ALP). Experimental results revealed how the subtle differences in the binding affinities between PPi and M in L.M (M is Zn2+, Cd2+, and Cu2+), could influence the cleavage of the phosphoester linkage in PPi by ALP. The DFT calculations further revealed that the hydrolytic cleavage of the metal ion coordinated phosphoester bond is kinetically faster than that for free PPi and thus, rationalized the observed difference in the cleavage of the phosphoester bond by an important mammalian enzyme such as ALP in the presence of different metal complexes.

1 aDas, Priyadip1 aChandar, Nellore, Bhanu1 aChourey, Shishir1 aAgarwalla, Hridesh1 aGanguly, Bishwajit1 aDas, Amitava uhttps://library.ncl.res.in/content/role-metal-ion-specific-recognition-pyrophosphate-ion-under-physiological-conditions-and-0