Hoechst 34580 tetra HCl is a marking dye from the Hoechst range. The Hoechst series are live cell nuclear labeling dyes. Hoechst binds nucleic acids via binding to the minor groove in the DNA double strand. Hoechst prefers to bind to A/T-rich DNA strands. At the same time, A/T-rich double-stranded DNA significantly enhances the fluorescence intensity. Hoechst can cross cell membranes and bind to living or fixed cells. The fluorescence intensity of Hoechst dye increases with increasing solution pH.

Physicochemical Properties

CAS #	2310135-08-9
Related CAS #	Hoechst 34580;23555-00-2
PubChem CID	131704503
Appearance	Light yellow to khaki solid powder
Hydrogen Bond Donor Count	6
Hydrogen Bond Acceptor Count	5
Rotatable Bond Count	4
Heavy Atom Count	38
Complexity	672
Defined Atom Stereocenter Count	0
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	Amyloid-β[1]
ln Vitro	Hoechst working solution preparation 1.1 Hoechst stock solution preparation Make a 1 mg/mL Hoechst stock solution using DMSO. Note: After aliquots, Hoechst storage solution should be kept at -4°C or -20°C out of direct sunlight. 1.2 Making the working solution: Use either PBS-diluted storage solution or heated serum-free cell culture medium, bringing the final concentration of the Hoechst working solution to 10 μg/mL. Note: Before using, please make sure that the Hoechst working fluid concentration is appropriate for the current circumstances. 2. Suspended cell staining (2.1): Centrifuge cells, add PBS, then wash twice for five minutes each time. The density of cells is 1×106/mL. 2.2 After adding 1 mL of Hoechst working solution, incubate for 3–10 minutes at room temperature. 2.3 Centrifuge for 3–4 minutes at 400 g, then remove the supernatant. 2.4 After adding PBS, wash the cells twice for five minutes each. 2.5 Re-suspend the cells in 1 milliliter of PBS or serum-free media, and use a flow cytometer or fluorescence microscope to observe. 3. Adherent cell staining (3.1): Grow adherent cells on sterile coverslips. 3.2 Aspirate extra culture medium after removing the coverslip from the medium. 3.3 Add 100 μL of the dye working solution, give the cells a full shake to cover them, and then let them sit for three to ten minutes. 3.4 Use a flow cytometer or fluorescence microscope to observe after aspirating the dye working solution and washing it twice in culture media for a total of five minutes each time. Observations 1. Kindly modify the Hoechst working fluid concentration based on the current circumstances. 2. This product may not be used for clinical diagnosis or treatment, nor may it be included into food or medication. It is intended solely for professional use in scientific study. 3. Please wear disposable gloves and a lab coat for your health and safety.
References	[1]. Discovery of DNA dyes Hoechst 34580 and 33342 as good candidates for inhibiting amyloid beta formation: in silico and in vitro study. J Comput Aided Mol Des. 2016 Aug;30(8):639-50.

Solubility Data

Solubility (In Vitro)	H2O: 2.67 mg/mL (4.47 mM)
Solubility (In Vivo)	Solubility in Formulation 1: 6.25 mg/mL (10.46 mM) in PBS (add these co-solvents sequentially from left to right, and one by one), clear solution; with sonication.  (Please use freshly prepared in vivo formulations for optimal results.)