HKOCl-4 (BXY2142) is a rhodium-based yellow fluorescent probe for the detection of hypochlorous acid with excellent sensitivity and selectivity compared to fluorescein probes. HKOCl-4 has longer absorption wavelength and better pH stability. Ex: 530 nm; Em 557 nm.

Physicochemical Properties

Molecular Formula	C38H35CL2NO7
Molecular Weight	688.593009233475
Exact Mass	687.179
CAS #	2031170-85-9
PubChem CID	122646992
Appearance	Yellow to orange solid powder
LogP	8.6
Hydrogen Bond Donor Count	1
Hydrogen Bond Acceptor Count	8
Rotatable Bond Count	8
Heavy Atom Count	48
Complexity	1180
Defined Atom Stereocenter Count	0
SMILES	N1(CCCC(OCC)=O)C2=C(C=C3C4(C5=C(C=CC=C5)C(=O)O4)C4=CC=C(OC5=CC(Cl)=C(O)C(Cl)=C5)C=C4OC3=C2)C(C)CC1(C)C
InChi Key	LUSCIMHITFMNOM-UHFFFAOYSA-N
InChi Code	InChI=1S/C38H35Cl2NO7/c1-5-45-34(42)11-8-14-41-31-19-33-28(18-25(31)21(2)20-37(41,3)4)38(26-10-7-6-9-24(26)36(44)48-38)27-13-12-22(17-32(27)47-33)46-23-15-29(39)35(43)30(40)16-23/h6-7,9-10,12-13,15-19,21,43H,5,8,11,14,20H2,1-4H3
Chemical Name	ethyl 4-[9'-(3,5-dichloro-4-hydroxyphenoxy)-2',2',4'-trimethyl-3-oxospiro[2-benzofuran-1,6'-3,4-dihydrochromeno[3,2-g]quinoline]-1'-yl]butanoate
HS Tariff Code	2934.99.9001
Storage	Powder-20°C 3 years 4°C 2 years In solvent -80°C 6 months -20°C 1 month Note: Please store this product in a sealed and protected environment (e.g. under nitrogen), avoid exposure to moisture and light.
Shipping Condition	Room temperature (This product is stable at ambient temperature for a few days during ordinary shipping and time spent in Customs)

Biological Activity

Targets	Ex: 530 nm; Em 557 nm
ln Vitro	HKOCl-4 (10 μM) exhibits a greater degree of florescence with an increase in hypochlorous acid concentration[1]. The fluorescence intensity of HKOCl-4 is >20 times higher than that of other analytes (1 equiv of OH and ONOO as well as 10 equiv of O2, NO, 1O2, ROO, TBHP, and H2O2), and it responds extremely quickly to 1 equiv of HOCl (hit a plateau within 2 min)[2]. After being evaluated on RAW264.7 macrophages up to 50 μM, HKOCl-4 was found to be non-toxic in living cells[2].
References	[1]. Diarylether-based fluorogenic probes for detection of hypochlorous acid or hydroxyl radical. Patent US20160312033. [2]. HKOCl-4: a rhodol-based yellow fluorescent probe for the detection of hypochlorous acid in living cells and tissues.

Solubility Data

Solubility (In Vitro)

DMSO: 200 mg/mL (290.45 mM)

Solubility (In Vivo)

Solubility in Formulation 1: 5 mg/mL (7.26 mM) in 10% DMSO + 90% (20% SBE-β-CD in Saline) (add these co-solvents sequentially from left to right, and one by one), suspension solution; with sonication. For example, if 1 mL of working solution is to be prepared, you can add 100 μL of 50.0 mg/mL clear DMSO stock solution to 900 μL of 20% SBE-β-CD physiological saline solution and mix evenly. Preparation of 20% SBE-β-CD in Saline (4°C，1 week): Dissolve 2 g SBE-β-CD in 10 mL saline to obtain a clear solution.  (Please use freshly prepared in vivo formulations for optimal results.)

Preparing Stock Solutions		1 mg	5 mg	10 mg
	1 mM	1.4522 mL	7.2612 mL	14.5224 mL
	5 mM	0.2904 mL	1.4522 mL	2.9045 mL
	10 mM	0.1452 mL	0.7261 mL	1.4522 mL

*Note: Please select an appropriate solvent for the preparation of stock solution based on your experiment needs. For most products, DMSO can be used for preparing stock solutions (e.g. 5 mM, 10 mM, or 20 mM concentration); some products with high aqueous solubility may be dissolved in water directly. Solubility information is available at the above Solubility Data section. Once the stock solution is prepared, aliquot it to routine usage volumes and store at -20°C or -80°C. Avoid repeated freeze and thaw cycles.