probe

Copper probe CF4 (Copper fluor CF4) is a monovalent copper (Cu⁺)-specific fluorescent sensor based on a rhodol dye scaffold. TCF4 exhibits a 1:1 stoichiometric binding ratio and remains stable at pH 6–8, suitable for in vivo imaging.

Alkyne-probe 1 is typically employed as an Alkyne-labeled fluorescent or chemical probe.

Biotin-probe 1, a non-radiolabeled probe, is applicable for in situ hybridization.

TAMRA-probe 1 is a fluorescent probe for labeling.

Protein arginine deiminases (PADs) catalyze the posttranslational modification of arginine residues on proteins to form citrulline, which plays a large role in regulating gene expression. Abnormally high PAD activity has been observed in a host of human diseases. Citrulline-specific probe-rhodamine is a highly sensitive, rhodamine phenylglyoxal-based fluorophore that specifically detects protein citrullination via a chemoselective reaction between glyoxal and citrulline. This chemical probe (comprised of a single isomer) is capable of reacting with any citrulline-containing protein and can be analyzed with fluorescent imaging (excitation 532 nm; emission 580 nm). When added at 100 μM for 30 minutes at acidic pH, this probe has a reported limit of detection of ~10 ng for citrullinated histone H3 and ~1 ng for autodeiminated PAD4.

Ninhydrin is a chromogenic analytical probe for the quantification of proteins and amino acids.

DDAO is a promising near-infrared (NIR) red fluorescent probe with a long emission wavelength (λem = 656 nm) and a tunable excitation wavelength (600-650 nm). It can be designed for detecting the activities of various enzymes such as β-galactosidase, sulfatase, protein phosphatase 2A, carboxylesterase 2, human albumin, and esterases.

Safranin O (Basic red 2) stains the lignified, embolic and keratinized parts of the plant, as well as chromatin and chromosomes in the nucleus. Safranin O is commonly used for the detection of cartilage, mucin and mast cell granules.

WSP-5 (Washington State Probe-5) is a fluorescent probe containing an active disulfide group, used for rapid detection of H2S in biological samples and cells.

H2S Fluorescent probe 1 (Compound 2) is a fluorescent probe for detecting hydrogen sulfide (H2S) with minimal cytotoxicity. When HS- is added to the DMSO solution of H2S Fluorescent probe 1, a new absorption peak appears at 485 nm. During the titration of HS-, the fluorescence intensity at 434 nm increases rapidly.

BTD probe-1 is a benzothiazine-based chemical selective probe used for the in vitro specific labeling of protein S-sulfinic acid. It selectively modifies sulfinic acid residues within proteins.

Cobalt(II) ions probe 1 (Compound L) is a fluorescent sensor designed to detect Co2+ in biological environments. It selectively binds with Co2+ even in the presence of other metal ions, exhibiting a specific response (Ex: 380 nm).

GSK-3βprobe-1 (10c) is a GSK-3β probe, characterized by an excitation wavelength of 341 nm and an emission wavelength of 574 nm, with a molar absorptivity of 3.51 × 10^4 L/mol·cm−1. This compound is utilized in Alzheimer's disease research.

Serum CG probe 1 (formula (9)) is a compound used for the determination of cholylglycine in serum.

Serum CG probe 2 (formula (15)) is a compound used for determining serum cholic glycinate.

Kyoto probe 1 is a fluorescent probe specifically designed for hiPSCs. It selectively labels human pluripotent stem cells and identifies them by recognizing the distinct expression patterns of ATP-binding cassette (ABC) transporters in hiPS cells compared to differentiated cells.

Flipper-TR probe (Compound FliptR probe) is a fluorescent probe specifically designed to measure cell membrane tension. It reports changes in membrane tension by altering its fluorescence lifetime and can be applied to a variety of organisms, including bacteria, yeast, mammals, and plants.

ZL-12A probe is a "stereoprobes" compound that facilitates the degradation of the TFIIH helicase, ERCC3. It achieves this by covalently modifying C342 to promote the degradation of ERCC3.

SARS-CoV-2 3CLpro probe-1 (Compound probe3) is a selective activity-based probe for the SARS-CoV-2 3CL protease. This compound is capable of detecting endogenously expressed 3CLpro in SARS-CoV-2 infected cells.

Probe-Cys is a water-soluble, selective near-infrared fluorescent probe for Cys (λex= 680 nm, λem=710 nm) that remains unaffected by Hcy, GSH, and HS-. This compound can react with the stimulant 1,4-dithiothreitol (DTT) and the inhibitor N-ethylmaleimide (NEM) in HepG2 cells and zebrafish for detecting endogenous Cys. Furthermore, Probe-Cys is applicable for imaging Cys in Arabidopsis thaliana. It offers a method for exploring cancer diagnostics and plant sulfur metabolism.

Sulfane Sulfur Probe 4 (SSP4) serves as a fluorescent probe targeting sulfane sulfur species, encompassing hydrogen sulfide-derived polysulfides, hydropersulfides, and persulfides generated endogenously. Upon interacting with these species, SSP4 undergoes a nucleophilic attack, leading to fluorescein production, characterized by 494/515 nm excitation/emission peaks, along with the generation of two 1,2-benzodithiol-3-one molecules. This compound has been instrumental in localizing H2S3 within primary mouse neurons and identifying polysulfides in L. japonicus seedling roots.

CTB Probe-1 (probe 1) serves as a small-molecule, lysosome-targeting fluorogenic probe designed for fluorescence imaging within living cells [1].

DPP-8/9 probe-1 (compound 20) is a fluorescent probe designed to specifically target and label Dipeptidyl Peptidase DPP8/9, allowing for its visualization through fluorescence microscopy in vitro when active. This compound incorporates a nitrobenzoxadiazole (NBD) tag, demonstrating a high affinity and selectivity for DPP8/9, with significant preference over other S9 family enzymes, evidenced by IC 50 values of 210 nM and 15 nM, respectively. [9] [1]

Fluorescent polyamine probe-1 (compound 15) is a linear polyamine probe characterized by its high uptake efficiency. It is employed in studying the transport systems into cancer cells [1].