CO probe 1 

CO probe 1 (probe 2) is a highly efficient fluorescent CO probe (Ex=493 nm) with an allyl ether reaction site. In the presence of PdCl₂, CO reduces Pd²⁺ to Pd⁰, triggering a Tsuji-Trost reaction that removes the allyl protecting group, releases fluorescein, and generates a significant fluorescence signal. CO probe 1 has high selectivity, rapid response (fluorescence enhancement of 150 times within 20 minutes), and low cytotoxicity, and can be used for real-time imaging of CO in living cells. CO probe 1 may be used to study pathological mechanisms involving CO signaling regulation, such as inflammation, vascular disease, or cancer^[1].

CO probe 1 CO imaging steps in living cells^[1]:
1. Before the cell imaging experiment, cells were seeded in 24-well culture plates overnight.
2. Set up control group and fluorescence group. Control group: Living cells were incubated with CO probe 1 (1 μM) at 37 °C for 30 minutes. Fluorescence group: Living cells were incubated with a mixture of CO probe 1 and PdCl₂ (1 μM each) at 37 °C for 30 minutes.
3. After the above two groups were incubated, they were washed three times with PBS and then imaged.
* For monitoring exogenous CO, HeLa cells were pretreated with CORM-3 (HY-100581) (1, 5, and 10 μM, respectively) at 37 °C for 30 min and then incubated with a mixture of CO probe 1 and PdCl₂ (1 μM each) at 37 °C for 30 min. Cells were washed with PBS buffer before imaging.
* For monitoring CO stimulated by heme, the procedure was essentially the same as for imaging exogenous CO, but heme (100 μM) was used instead of CORM 3 (HY-100581) in the cell pretreatment.

MedChemExpress (MCE) has not independently confirmed the accuracy of these methods. They are for reference only.

481.32

C₂₆H₁₈Cl₂O₅

1043865-37-7

Solid

Light yellow to yellow

O=C1OC2(C3=CC(Cl)=C(C=C3OC4=CC(OCC=C)=C(C=C42)Cl)OCC=C)C5=C1C=CC=C5

Room temperature in continental US; may vary elsewhere.

-20°C, protect from light

*In solvent : -80°C, 6 months; -20°C, 1 month (protect from light)

• [1]. Feng S, et al. Allyl Fluorescein Ethers as Promising Fluorescent Probes for Carbon Monoxide Imaging in Living Cells. Anal Chem. 2017 Mar 21;89(6):3754-3760.  [Content Brief]