insensitivity in the biologically relevant range. Compared with
SZn-Mito, this probe shows 10-fold larger turn-on response,
2-fold larger Fd value, and 2-fold stronger Zn2+ binding affinity,
and can selectively detect [Zn2+
] in live cells and tissues at a
m
depth of 100–200 mm with a brighter and clearer TPM image.
This work was supported by the Korea Healthcare technology
R&D Project, Ministry of Health & Welfare, Republic of Korea
(A111182) and the NRF grants (No. 2011-0028663) and Priority
Research Centers Program through the NRF funded by the
Ministry of Education, Science and Technology (2011-0022978),
and Ajou university research fellowship of 2011.
Fig. 3 Images of a rat hippocampal slice stained with 20 mM
SZn2-Mito for 1 h. (a) Bright-field images of the CA1–CA3 regions
as well as dentate gyrus (DG) at 10ꢀ magnification. (b) 10 TPM
images along the z-direction at the depths of approximately 100–200 mm
were accumulated. (c–e) Magnification at 40ꢀ in the DG regions
(red circle in (b)) at a depth of B100 mm (c) before and (d) after
addition of 150 mM DTDP to the imaging solution. (e) After addition of
10 mM CCCP to (d). Scale bars: (a) 300 and (e) 75 mm.
Notes and references
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100 mM pyrithione (2-mercaptopyridine N-oxide), a reagent
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[Zn2+
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m
We further investigated the utility of SZn2-Mito in tissue
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[Zn2+
] (Fig. 3b). They reveal marked TPEF in the CA3 and
m
DG regions (Fig. 3b).11 At a higher magnification, the [Zn2+
]
m
distribution in the DG region is clearly visualized (Fig. 3c). As
observed in the HeLa cells, the TPEF intensity increased after
addition of DTDP and decreased upon treatment of CCCP,
thereby providing a strong evidence that the bright regions
reflect the [Zn2+
]
(Fig. 3d,e). Moreover, the TPM images
m
obtained at a depth of 100–200 mm revealed the [Zn2+
]
m
13 E. U. Akkaya, M. E. Huston and A. W. Czarnik, J. Am. Chem.
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]
at a depth of 100–200 mm in
m
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SZn2-Mito.
In conclusion, we have developed a mitochondrial-targeted
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c
4548 Chem. Commun., 2012, 48, 4546–4548
This journal is The Royal Society of Chemistry 2012