Table 1.

Summary of tools reported in Section 4.

Evaluation Method	Detection	Tool	Application	Key Feature	Notes	Ref
ROS	Hypochlorous acid (HOCl)	FDOCl-1 a	Imaging	Near-infrared (NIR) emission, turn-on probe		[50]
		FDOCl-18 a		Visualization in the off state (additionally to the above)		[51]
		LYSO- & MITO-TP a		Targeted imaging of mitochondria or lysosome		[52]
	Hypobromous acid (HOBr)	RhSN-mito a		Ratiometric probe	Selective over HOCl	[53]
	All hypohalous acids (HOX)	Hypocrates b		First biosensor specific for HOX, ratiometric imaging		[54]
	Superoxide anion (O2•−)	DMPS-O a		Turn-on, mitochondria targeting probe with NIR emission		[55]
		HQ a		Two-photon excitability		[56]
		MitoHCy-NH2 a		Detection of ROS generated by a certain protein		[57]
	Peroxynitrite (ONOO−)	MITO-CC a		FRET-based, mitochondria targeting probe with two-photon excitability		[58]
		sfGFP(66Thy) b		Turn-on reporters with non-natural amino acids		[59]
		pnGFP-Ultra b				[60]
	Hydrogen peroxide (H2O2)	Hyp-L a	Imaging/ Proteomics	Labeling of H2O2-surrounding proteins		[61]
		FROG/B b	Imaging	Excitation state intramolecular proton transfer (ESIPT) mechanism	Requires a single excitation wavelength but its emission is redox-dependent	[62]
Damaged proteins	Oxidized methionine	ReACT a	Proteomics	First selective probe for methionine	Note that results regarding methionine oxidation are by elimination	[63]
	Sulfonic acid	BTD a		High reactivity towards sulfenic acid-modified proteins	Commercial	[64]
		WYneN a		10-fold increase in kinetics (compared to BTD)		[65]
		CysOx a	Imaging	Fluorogenic probe for live cell imaging		[66]
	Sulfinic acid	NO-Bio a	Proteomics	High selectivity over sulfenic acid	Commercial	[67]
		DiaAlk a		Additional selectivity (compared to NO-Bio) over cysteine	Commercial	[68]
	Carbonylation	m-APA a		High reaction kinetics and selectivity		[69]
		TFCH a	Imaging	High sensitivity and suitable for live cell imaging		[70]

^a Small molecule probe, ^b genetically encoded reporter.