dissociation constant (KdTP) of 0.45 ꢂ 0.01 mM, and can
selectively detect Hg2+ in live cells and fish organs at
80–150 mm depth by TPM without interference from other
metal ions or membrane bound probes. Better than the
currently available probes, this novel probe can not only
visualize the site of Hg2+ accumulation, but also estimate
trace amounts of [Hg2+] in fresh fish organs by TPM.
This work was supported by a NRF grant (R0A-2007-000-
20027-0). CSL, DWK, JHH, and HLH were supported by a
BK21 scholarship.
Notes and references
Fig. 3 (a–d) TPM images of kidney, heart, gill, and liver of Oryzias
latipes obtained at 100 mm depth by magnification at 10ꢄ. (e–h) The
regions indicated by the red boxes in a–d are magnified at 100ꢄ. All
organs were stained with 10 mM AHg1 and the TPM images were
obtained by collecting the TPEF at 500–620 nm upon excitation at
780 nm with fs pulses. Scale bar, 300 (a–d) and 30 mm (e–h).
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Fig. 4 Relative TPEF intensity in kidney, heart, liver and gill of
Oryzias latipes after exposure to 2 ppb Hg2+ for 1 and 3 days. The
organs were incubated with AHg1 (10 mM) for 30 min and the TPEF
was collected at 500–620 nm upon excitation with fs pulses at 780 nm.
The columns and error bars represent the average and standard
deviation of the TPEF intensities from 70 TPM images.
ꢁc
This journal is The Royal Society of Chemistry 2010
2390 | Chem. Commun., 2010, 46, 2388–2390