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Photoluminescent DNA binding and cytotoxic activity of a platinum(II) complex bearing a tetradentate ?-diketiminate ligand.

ABSTRACT: A platinum(II) complex of a monoanionic, tetradentate ?-diketiminate (BDI) ligand with pendant quinoline arms, BDI(QQ)H, is reported. The complex, [Pt(BDI(QQ))]Cl, is emissive in DMSO, but non-emissive in aqueous buffer. Upon binding DNA in buffer, however, a 150-fold turn-on in emission intensity occurs. Dynamic light scattering and (1)H NMR spectroscopy indicate that [Pt(BDI(QQ))]Cl forms non-emissive aggregates in aqueous solution; DNA-binding disperses the aggregates leading to the large emission turn-on response. The cytotoxic activity of the complex, measured in two cancer cell lines, is comparable to or better than that of the established anticancer drug cisplatin.

SUBMITTER: Hope JM

PROVIDER: S-EPMC3566370 | biostudies-literature | 2013 Mar

REPOSITORIES: biostudies-literature

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Photoluminescent DNA binding and cytotoxic activity of a platinum(II) complex bearing a tetradentate β-diketiminate ligand.

Hope Jennifer M JM Wilson Justin J JJ Lippard Stephen J SJ

Dalton transactions (Cambridge, England : 2003) 20121112 9

A platinum(II) complex of a monoanionic, tetradentate β-diketiminate (BDI) ligand with pendant quinoline arms, BDI(QQ)H, is reported. The complex, [Pt(BDI(QQ))]Cl, is emissive in DMSO, but non-emissive in aqueous buffer. Upon binding DNA in buffer, however, a 150-fold turn-on in emission intensity occurs. Dynamic light scattering and (1)H NMR spectroscopy indicate that [Pt(BDI(QQ))]Cl forms non-emissive aggregates in aqueous solution; DNA-binding disperses the aggregates leading to the large emi ...[more]

PMID: 23143731

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