4 methylumbelliferyl 2 sulfamino 2 deoxy α d glucopyranoside (sodium salt)

4-Methylumbelliferyl 2-sulfamino-2-deoxy-α-D-Glucopyranoside (4-MU-α-GlcNS) is a fluorogenic substrate of heparin sulphamidase. Heparin sulphamidase cleaves 4-MU-α-GlcNS to yield 4-MU-α-GlcNH2, which is then cleaved by α-glucosaminidase to release the fluorescent product 4-MU, which displays an emission maxima of 445-454 nm. The excitation maxima for 4-MU is pH-dependent: 330, 370, and 385 nm at pH 4.6, 7.4, and 10.4, respectively. 4-MU-α-GlcNS has been used to quantify heparin sulphamidase deficiencies associated with Mucopolisaccaridosis IIIA and other lysosomal disorders.

Fast red TR salt hemi(zinc chloride) is a red diazo dye with λmax = 284 nm, commonly used as a chromogenic substrate for alkaline phosphatase (AP) and in immunohisto-chemistry to detect specific proteins or antigens in tissue sections.

2-(4-Hydroxyphenylazo)benzoicacid is a spectrophotometric probe that shows changes in absorption spectra upon binding to proteins and binds to bovine serum proteins.

4-Di-1-ASP is a positively charged fluorescent dye used to label glioma cells in live brain tissue and can also be used to observe mitochondria in live cells, with λex λem = 475 606 nm.

6-Ethyl-7-hydroxy-4-methylchromen-2-one is a fluorescent dye.

Fluo-4 AM is a cell-permeable calcium ion (Ca²⁺) fluorescent indicator/chemical probe suitable for fluorescence imaging, flow cytometry, and plate screening, with an excitation wavelength of approximately 488 nm and an emission wavelength of 512–520 nm.

DAPI Dihydrochloride (FxCycle Violet) is A cell-permeable fluorescent probe. By binding to small forests rich in A-T DNA sequences, it is used to stain DNA and chromosomes, with a preference for DNA rich in adenine and thymine.

Compound 2f, chemically known as 4-Methyl-7-(2-nitrophenoxy)-2H-chromen-2-one, is a selenium alcohol fluorescent probe designed on the nucleophilic aromatic substitution mechanism. It exhibits selective recognition of selenols in neutral aqueous solutions without significant interference from biological thiols, amines, or alcohols. This compound is utilized for quantifying selenium content in selenoproteins and imaging the activity of endogenous selenols in living cells.

7-(2,4-Dinitrophenoxy)-4-methyl-2H-chromen-2-one (Compound 1) serves as a fluorescent probe for detecting hydrogen sulfide (H2S). It is characterized by a low detection limit (4×10^-6 mol L), high selectivity, and great sensitivity. At a concentration of 150 µg mL, it exhibits negligible cytotoxicity. The excitation wavelength is 331 nm, while in DMSO solvent, it emits at approximately 385 nm; upon addition of HS-, the fluorescence intensity significantly increases around 392 nm.

Asante potassium green-1 AM is a membrane-permeable, acetoxymethyl (AM) ester-form fluorescent potassium indicator that emits in the yellow-green spectrum.Asante potassium green-1 AM is specifically tailored to measure dynamic changes in potassium ion concentrations in intracellular and extracellular environments characterized by high potassium concentrations, as it possesses a lower potassium binding affinity compared to other indicators like IPG-2 and IPG-4.

4-Methyl-7-(4-nitrophenoxy)-2H-chromen-2-one is a fluorescent coumarin derivative with excitation and emission wavelengths of 323 nm and 445 nm, respectively.

BODIPY 493/503 carboxylic acid is a green BODIPY fluorescent dye with lipophilic properties, commonly used for staining lipids, membranes, and other neutral lipids in live and fixed cells.

MMTr-Cy3-OH is a Cy3-derived dye. The MMTr protecting group ensures stability of the intermediate product, while the hydroxyl group facilitates subsequent reactions. Cy3 (Sulfo-Cyanine 3) is an amine-reactive cyanine orange dye with excitation/emission wavelengths of 550/570 nm, commonly employed for fluorescent labelling of proteins and nucleic acids.

4-(2-Azidoethyl)phenol (Ph_N3) is a clickable APEX2 probe. It demonstrates dependable labeling capabilities and offers two biotinylation pathways for subsequent analysis.

Lumogallion (4-Chloro-3-(2,4-dihydroxyphenylazo)-2-hydroxybenzene-1-sulfonic acid) is an azo reagent used in the determination of metal ions, such as the research of V, Fe, and Al.

Tc-Me2P is a novel 99mTc-labeled propylene amine oxime (PnAO) derivative, which includes two 4-methyl-2-nitroimidazole groups. Primarily, Tc-Me2P serves as an imaging agent for hypoxic tumors by specifically binding to low-oxygen areas within tumor tissue. It is applicable in single-photon emission computed tomography (SPECT) and positron emission tomography (PET) imaging for detecting tumor hypoxia. Additionally, Tc-Me2P can be utilized to study the targeting properties of its diverse chemical structures in tumor versus normal tissue.

cis-Parinaric acid is a naturally occurring polyunsaturated fatty acid containing an unusual conjugated (Z,E,E,Z) tetraene. This chromophore provides for a natural fluorescence at 432 nm with an excitation wavelength at 320 nm. cis-Parinaric acid occurs naturally in the seeds of the Makita tree, a tropical rainforest tree indigenous to Fiji. Makita seeds are inedible, and this toxicity may be due at least in part to the unstable conjugated fatty acids, including cis-parinaric acid, contained within the seed. cis-Parinaric acid has been used for the measurement of phospholipase activity, lipase activity, and as an indicator of lipid peroxidation.[1][2][3][4]

STY-BODIPY is a styrene-conjugated fluorogenic probe for radical-trapping antioxidant (RTA) activity.1 Co-autoxidation of the STY-BODIPY signal carrier and a hydrocarbon co-substrate can be quantified by monitoring the loss of absorbance at 571 nm. STY-BODIPY has been used to measure the activity of RTAs, as well as the kinetics and stoichiometry of RTA reactions in cell-free assays.1,2,3References1. Haidasz, E.A., Van Kessel, A.T.M., and Pratt, D.A. A continuous visible light spectrophotometric approach to accurately determine the reactivity of radical-trapping antioxidants. J. Org. Chem. 81(3), 737-744 (2016).2. Shah, R., Shchepinov, M.S., and Pratt, D.A. Resolving the role of lipoxygenases in the initiation and execution of ferroptosis. ACS Cent. Sci. 4(3), 387-396 (2018).3. Chauvin, J.-P.R., Haidasz, E.A., Griesser, M., et al. Polysulfide-1-oxides react with peroxyl radicals as quickly as hindered phenolic antioxidants and do so by a surprising concerted homolytic substitution. Chem. Sci. 7(10), 6347-6356 (2016). STY-BODIPY is a styrene-conjugated fluorogenic probe for radical-trapping antioxidant (RTA) activity.1 Co-autoxidation of the STY-BODIPY signal carrier and a hydrocarbon co-substrate can be quantified by monitoring the loss of absorbance at 571 nm. STY-BODIPY has been used to measure the activity of RTAs, as well as the kinetics and stoichiometry of RTA reactions in cell-free assays.1,2,3 References1. Haidasz, E.A., Van Kessel, A.T.M., and Pratt, D.A. A continuous visible light spectrophotometric approach to accurately determine the reactivity of radical-trapping antioxidants. J. Org. Chem. 81(3), 737-744 (2016).2. Shah, R., Shchepinov, M.S., and Pratt, D.A. Resolving the role of lipoxygenases in the initiation and execution of ferroptosis. ACS Cent. Sci. 4(3), 387-396 (2018).3. Chauvin, J.-P.R., Haidasz, E.A., Griesser, M., et al. Polysulfide-1-oxides react with peroxyl radicals as quickly as hindered phenolic antioxidants and do so by a surprising concerted homolytic substitution. Chem. Sci. 7(10), 6347-6356 (2016).

bis-ANS is a high-affinity non-covalent extrinsic fluorescent dye used to analyze protein conformation.[1] Its predominant interaction with proteins is through its hydrophobic phenyl and naphthyl rings.[2] bis-ANS has an excitation maxima of 390 nm.[3] It has an emission maximum of 523 nm when free in solution but undergoes a blue shift with an increase in fluorescence intensity when bound to protein; for example, when bound to intestinal fatty acid binding protein (FAPB2) it has emission maxima of 484-496 nm. bis-ANS has been used to label mechanically damaged neurons in acute brain slices.4 It also potently inhibits microtubule assembly.[5],[6]

7-Azido-4-methylcoumarin (7-azido-4-methyl-2H-chromen-2-one) is a fluorescent photoactive probe used in the study of human phenol sulfotransferase (SULT1A1 or P-PST-1) substrate binding sites through photoaffinity labeling.

7-Fluoro-2,1,3-benzoxadiazole-4-sulfonate (SBD-F) is a thiol-reactive fluorogenic probe.1It has been used to quantify the levels of homocysteine, cysteine, and cysteamine in human plasma.2SBD-F displays excitation emission maxima of 380 515 nm, respectively.1 1.Imai, K., Toyo'oka, T., and Watanabe, Y.A novel fluorogenic reagent for thiols: Ammonium 7-fluorobenzo-2-oxa-1,3-diazole-4-sulfonateAnal. Biochem.128(2)471-473(1983) 2.Ichinose, S., Nakamura, M., Maeda, M., et al.A validated HPLC-fluorescence method with a semi-micro column for routine determination of homocysteine, cysteine and cysteamine, and the relation between the thiol derivatives in normal human plasmaBiomed. Chromatogr.23(9)935-939(2009)

Z-(L-Arg)-AMC is a fluorogenic substrate for trypsin, cathepsin B, and cathepsin H.1,2Upon enzymatic cleavage by trypsin, cathepsin B, or cathepsin H, 7-amino-4-methylcoumarin (AMC) is released and its fluorescence can be used to quantify trypsin, cathepsin B, and cathepsin H activity. AMC displays excitation emission maxima of 340-360 440-460 nm, respectively. 1.Zimmerman, M., Ashe, B., Yurewicz, E.C., et al.Sensitive assays for trypsin, elastase, and chymotrypsin using new fluorogenic substratesAnal. Biochem.78(1)47-51(1977) 2.Brindley, P.J., Kalinna, B.H., Dalton, J.P., et al.Proteolytic degradation of host hemoglobin by schistosomesMol. Biochem. Parasitol.89(1)1-9(1997)

4-Methylumbelliferyl-β-D-galactoside (MUG) is a fluorogenic substrate for β-galactosidase (β-gal).1Hydrolysis of MUG by β-gal releases the fluorescent moiety 4-MU, which displays a pH-dependent excitation maximum of 330, 370, and 385 nm at pH 4.6, 7.4, and 10.4, respectively, and an emission maximum between 445-454 nm.2MUG has been used to detect β-gal activity in intact bacteria, yeast, and mammalian cells.1 1.Vidal-Aroca, F., Giannattasio, M., Brunelli, E., et al.One-step high-throughput assay for quantitative detection of β-galactosidase activity in intact Gram-negative bacteria, yeast, and mammalian cellsBiotechniques40(4)433-434(2006) 2.Zhi, H., Wang, J., Wang, S., et al.Fluorescent properties of hymecromone and fluorimetric analysis of hymecromone in compound dantong capsuleJ. Spectrosc.1(1)147128(2013)