1 research outputs found
Supramolecular Au<sup>I</sup>–Cu<sup>I</sup> Complexes as New Luminescent Labels for Covalent Bioconjugation
Two new supramolecular organometallic
complexes, namely, [Au<sub>6</sub>Cu<sub>2</sub>(C<sub>2</sub>C<sub>6</sub>H<sub>4</sub><b>CHO</b>)<sub>6</sub>(PPh<sub>2</sub>C<sub>6</sub>H<sub>4</sub>PPh<sub>2</sub>)<sub>3</sub>]Â(PF<sub>6</sub>)<sub>2</sub> and [Au<sub>6</sub>Cu<sub>2</sub>(C<sub>2</sub>C<sub>6</sub>H<sub>4</sub><b>NCS</b>)<sub>6</sub>(PPh<sub>2</sub>C<sub>6</sub>H<sub>4</sub>PPh<sub>2</sub>)<sub>3</sub>]Â(PF<sub>6</sub>)<sub>2</sub>, with highly
reactive aldehyde and isothiocyanate groups have been synthesized
and characterized using X-ray crystallography, ESI mass spectrometry,
and NMR spectroscopy. The compounds obtained demonstrated bright emission
in solution with the excited-state lifetime in microsecond domain
both under single- and two-photon excitation. The luminescent complexes
were found to be suitable for bioconjugation in aqueous media. In
particular, they are able to form the covalent conjugates with proteins
of different molecular size (soybean trypsin inhibitor, human serum
albumin, rabbit anti-HSA antibodies). The conjugates demonstrated
a high level of the phosphorescent emission from the covalently bound
label, excellent solubility, and high stability in physiological media.
The highest quantum yield, storage stability, and luminance were detected
for bioconjugates formed by covalent attachment of the aldehyde-bearing
supramolecular Au<sup>I</sup>–Cu<sup>I</sup> complex. The measured
biological activity of one of the labeled model proteins clearly showed
that introduced label did not prevent the biorecognition and specific
protein–protein complex formation that was extremely important
for the application of the conjugates in biomolecular detection and
imaging