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G Nageswara Rao

Publications and source records attributed to G Nageswara Rao.

4 recordsLinked to original sources
PubMed2006

A water-soluble fluorescent fluoride ion probe based on Alizarin Red S-Al(III) complex.

A new water-soluble fluorescent fluoride ion signaling system has been developed based on the ligand exchange mechanism in aqueous medium. This procedure is based on the exchange of two Alizarin Red S (ARS) molecules coordinated to Al(III) by fluoride ion without interference from other common anions. The binary complex of ARS with Al(III) provides a sensitive signaling system for fluoride ion in the concentration range from 5x10(-6) to 3x10(-4) M. The ligand exchange reaction of ARS-Al(III) complex with fluoride ion has been investigated by UV-vis and fluorescence spectroscopies combined with the AM1 semi-empirical quantum chemical calculations. The pale orange fluorescence (lambdamax=575 nm) exhibited by the complex upon excitation at 435 nm decreases in intensity with fluoride addition with a detection limit of 0.1 mg L-1.

Aluminum↗
PubMed2006

Fluoride ion detection by 8-hydroxyquinoline-Zr(IV)-EDTA complex.

A simple fluorescent detection based on the ligand exchange mechanism is proposed for the fluoride ion in aqueous media. This procedure is based on the exchange of 8-hydroxyquinoline (oxine) coordinated to Zr(IV) by fluoride ion without interference from other common anions. The ternary complex of oxine with [Zr(H(2)O)(2)EDTA].2H(2)O formed by replacing two water molecules in aqueous solution provides a sensitive signalling system for fluoride ion in the concentration range from 6 x 10(-7)M to 8 x 10(-4)M. The green fluorescence (lambda(max)=532 nm) exhibited by the complex upon excitation at 247 nm decreases in intensity with fluoride addition with a detection limit of 12 ppb. The complexation reaction between oxine and Zr(IV)-EDTA and the ligand exchange reaction with fluoride ion has been investigated by UV-vis and fluorescence spectroscopies combined with the PM3 semi-empirical quantum chemical calculations. Job's method of continuous variation and the molar ratio method ascertain a 1:1 stoichiometry composition of the chelate in aqueous media.

Fluorides↗
PubMed2005

DoD: Database of Databases--updated molecular biology databases.

Database of Databases (DoD) is a collection of molecular biology databases extracted from Nucleic Acids Research, 2005 Database issue. DoD is constructed using javascript and html code. The 14 categories of 719 databases are provided with a search option, keyword help and database description linked to respective pages. Keyword help lists the search strings used to perform an individual search against categorized databases. Database description provides brief information about the database with a link to full-text article and main web page. DoD is available online and can be accessed at http://www.progenebio.in/DoD/DoD.htm.

Computational Biology↗