Recent Advances of Fe(II) Fluorescence Probes Based on N-Oxide Structure

doi:10.6023/cjoc202407041

Abstract

Iron is widely distributed in the human body, participating in numerous biochemical reactions. Iron exists in the forms of Fe^2＋ and Fe^3＋ in cells, playing crucial roles in maintaining normal cellular functions. In the reducing environment of living cells, the labile iron primarily exists in the form of Fe^2＋ ions. The labile Fe^2＋ can serve as a catalyst for the Fenton reaction, generating reactive oxygen species (ROS) within the cell, which can cause severe damage to the cell and lead to a range of related diseases. Therefore, visual monitoring Fe^2＋ in the physiological environment is necessary to contribute to a deeper understanding of the pathogenesis and progression of the disease. In recent years, several researchers have focused on designing and synthesizing fluorescent probes with excellent optical properties that can be used to monitor Fe^2＋ in vivo and in vitro. Among them, the N-oxide-based fluorescence probes have been concerned by researchers because of its advantages of strong selectivity, high sensitivity, and in-situ real-time imaging. The structures, design considerations, optical properties, and applications of N-oxide-based Fe^2＋ fluorescence probes are discussed.

Key words: Fe^2＋, N-oxide chemistry, fluorescence probe, bioimaging

Cite this article

Hanyue Xiang, Shaoyin Wei, Yuji Wang, Nao Xiao. Recent Advances of Fe(II) Fluorescence Probes Based on N-Oxide Structure[J]. Chinese Journal of Organic Chemistry, 2025, 45(4): 1137-1152.

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Probe	E_x/E_m/nm	Time/min	Solvent	Response mode	Co-localization
1	540/575	60	HEPES buffer	Turn-On	—
2	550/575	20	HEPES buffer (0.2% DMF)	Turn-On	Lysosome
3	550/578	60	HEPES buffer (0.2% DMF)	Turn-On	Lysosome
4	515/535	60	HEPES buffer (0.2% DMF)	Turn-On	—
5	515/535	60	HEPES buffer (0.2% DMF)	Turn-On	—
6	575/660	30	HEPES buffer	Turn-On	Endoplasmic reticulum
7	580/630	10	HEPES buffer (5% MeOH)	Turn-On	—
8	630/665	30	HEPES buffer (30% dioxane)	Turn-On	Golgi
9	490/535	30	HEPES buffer (0.2% DMSO)	Turn-On	—
10	400/515	—	HEPES buffer (5% DMSO)	Turn-On	—
11	390/460	60	HEPES buffer (0.2% DMSO)	Turn-On	—
12	540/690	15	PBS buffer (50% DMSO)	Turn-On Two-photon	—
13	480/630	5	Sodium borate buffer (pH=7.4)	Turn-On	—
14	540/700	5	HEPES buffer (40% DMSO)	Turn-On	Lipid droplet
15	400/675	5	PBS buffer (40% DMSO)	Turn-On	—
16	467/625	20	PBS buffer (30% EtOH)	Turn-On	—
17	540/720	5	PBS buffer (2.5% EtOH, 1 mmol/L CTAB)	Turn-On	Lysosome
18	362/519	10	PBS buffer	Turn-On	—
19	365/520	10	PBS buffer	Turn-On	—
20	360/515	10	PBS buffer	Turn-On	—
21	350/489	20	Tris-HCl buffer (20% DMSO)	Turn-On	—
22	295/495	30	HEPES buffer	Turn-On	Endoplasmic reticulum
23	425/603	0.67	PBS buffer (20% EtOH)	Turn-On	—
24	380/495	1	PBS buffer (20% EtOH)	Turn-On	—
25	640/671	2	DMSO (1% TFA)	Turn-Off	Lysosome
26	370/486	0.42	PBS solution (90% ACN, 10 mmol/L, v/v)	Turn-On	—
27	400/518	0.58	PBS solution (90% ACN, 10 mmol/L, v/v)	Turn-On	—
28	510/535	30	HEPES buffer	Turn-On	—
29	540/575	60	HEPES buffer (0.2% DMSO)	Turn-On	—
30	540/575	60	HEPES buffer (0.2% DMSO)	Turn-On	Cell membrane
31	430/675	30	Tris-HCl buffer (30% DMSO)	Ratiometric	—
32	395/540	30	Aqueous solution (0.5% CH₃CN)	Turn-On	—
33	450/530	50	HEPES buffer	Turn-On	—
34	456/640	10	PBS buffer (1% DMSO, 1 mmol/L CTAB)	Turn-On Two-photon	Lysosome

Probe	E_x/E_m/nm	Time/min	Solvent	Response mode	Co-localization
1	540/575	60	HEPES buffer	Turn-On	—
2	550/575	20	HEPES buffer (0.2% DMF)	Turn-On	Lysosome
3	550/578	60	HEPES buffer (0.2% DMF)	Turn-On	Lysosome
4	515/535	60	HEPES buffer (0.2% DMF)	Turn-On	—
5	515/535	60	HEPES buffer (0.2% DMF)	Turn-On	—
6	575/660	30	HEPES buffer	Turn-On	Endoplasmic reticulum
7	580/630	10	HEPES buffer (5% MeOH)	Turn-On	—
8	630/665	30	HEPES buffer (30% dioxane)	Turn-On	Golgi
9	490/535	30	HEPES buffer (0.2% DMSO)	Turn-On	—
10	400/515	—	HEPES buffer (5% DMSO)	Turn-On	—
11	390/460	60	HEPES buffer (0.2% DMSO)	Turn-On	—
12	540/690	15	PBS buffer (50% DMSO)	Turn-On Two-photon	—
13	480/630	5	Sodium borate buffer (pH=7.4)	Turn-On	—
14	540/700	5	HEPES buffer (40% DMSO)	Turn-On	Lipid droplet
15	400/675	5	PBS buffer (40% DMSO)	Turn-On	—
16	467/625	20	PBS buffer (30% EtOH)	Turn-On	—
17	540/720	5	PBS buffer (2.5% EtOH, 1 mmol/L CTAB)	Turn-On	Lysosome
18	362/519	10	PBS buffer	Turn-On	—
19	365/520	10	PBS buffer	Turn-On	—
20	360/515	10	PBS buffer	Turn-On	—
21	350/489	20	Tris-HCl buffer (20% DMSO)	Turn-On	—
22	295/495	30	HEPES buffer	Turn-On	Endoplasmic reticulum
23	425/603	0.67	PBS buffer (20% EtOH)	Turn-On	—
24	380/495	1	PBS buffer (20% EtOH)	Turn-On	—
25	640/671	2	DMSO (1% TFA)	Turn-Off	Lysosome
26	370/486	0.42	PBS solution (90% ACN, 10 mmol/L, v/v)	Turn-On	—
27	400/518	0.58	PBS solution (90% ACN, 10 mmol/L, v/v)	Turn-On	—
28	510/535	30	HEPES buffer	Turn-On	—
29	540/575	60	HEPES buffer (0.2% DMSO)	Turn-On	—
30	540/575	60	HEPES buffer (0.2% DMSO)	Turn-On	Cell membrane
31	430/675	30	Tris-HCl buffer (30% DMSO)	Ratiometric	—
32	395/540	30	Aqueous solution (0.5% CH₃CN)	Turn-On	—
33	450/530	50	HEPES buffer	Turn-On	—
34	456/640	10	PBS buffer (1% DMSO, 1 mmol/L CTAB)	Turn-On Two-photon	Lysosome

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