Hoechst 33342 trihydrochloride is a membrane permeant blue fluorescent DNA stain.

Dye reagent^[1]
DNA Stain^[1]

Hoechst 33342 binds to adenine-thymine-rich regions of DNA in the minor groove. On binding to DNA, the fluorescence greatly increases. This protocol describes the use of Hoechst 33342 to label nuclear DNA of cells grown in culture. Hoechst 33342 can also be used to stain fixed cells by substituting Hoechst 33342 for DAPI^[1].

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

561.93

C₂₇H₃₁Cl₃N₆O

875756-97-1

Room temperature in continental US; may vary elsewhere.

4deg;C, sealed storage, away from moisture and light

*该产品在溶液状态不稳定，建议您现用现配，即刻使用。

DMSO : ≥ 46 mg/mL (81.86 mM)

H₂O : ≥ 5.6 mg/mL (9.97 mM)

* “≥” means soluble, but saturation unknown.

请根据产品在不同溶剂中的溶解度，选择合适的溶剂配制储备液；该产品在溶液状态不稳定，建议您现用现配，即刻使用。

• [1]. Chazotte B. Labeling nuclear DNA with hoechst 33342. Cold Spring Harb Protoc. 2011 Jan 1;2011(1):pdb.prot5557.

Labeling Nuclear DNA with Hoechst 33342^[1] Step 1, Dilute the Hoechst stock solution 1:100 in H₂O for use in labeling. Step 2, Aspirate the cell medium from cells grown on coverslips. Rinse the cells three times with PBS⁺. Step 3, Incubate the cells in the Hoechst labeling solution (from Step 1) for 10-30 min at room temperature. Step 4, Aspirate the labeling solution. Rinse the cells three times in PBS⁺. Step 5, Mount the coverslips. Step 6, Image the cells (λex ~353 nm, λem ~483 nm for Hoechst 33342)^[1].

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

• [1]. Chazotte B. Labeling nuclear DNA with hoechst 33342. Cold Spring Harb Protoc. 2011 Jan 1;2011(1):pdb.prot5557.

Hoechst 33258 trihydrochloride is a fluorescent dyes, which can be used as a cell dye for DNA.

IC50: 51.31±4.56 μM (HeLa cell), 32.43±3.27 μM (HL60 cell), 15.42±2.16 μM (U937 cell)^[1]

Hoechst 33258, a fluorescent compound with a head-to-tail bis-benzimidazole structure, is initially found to be cytotoxic against L1210 murine leukemia. Hoechst 33258 is evaluated for their cytotoxicity against human tumor cell lines, which are cervix carcinoma cell line (HeLa), Human promyelocytic leukemia cell (HL60) and U937 cell Line. The IC₅₀ determined in the case of HeLa, HL60 and U937 is 51.31±4.56, 32.43±3.27 and 15.42±2.16 μM for Hoechst 33258, respectively^[1]. The cytotoxic property of Hoechst 33258 is investigated on a panel of seven tumour cell lines of different histological origin and Madine-Darby canine kidney (MDCK) normal cells. All cell lines, except MCF-7, exposed to Hoechst 33258 exhibit GI₅₀ from 84×10^-6 to 191.5×10^-6 mol/dm³. Under the same experimental conditions, Hoechst 33258, used as a binder reference compound, stops the cell cycle in S phase and G0/G1^[2].

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

533.88

C₂₅H₂₇Cl₃N₆O

23491-45-4

Room temperature in continental US; may vary elsewhere.

4deg;C, sealed storage, away from moisture and light

*In solvent : -80deg;C, 6 months; -20deg;C, 1 month (sealed storage, away from moisture and light)

H₂O : ≥ 72.85 mg/mL (136.45 mM)

* “≥” means soluble, but saturation unknown.

请根据产品在不同溶剂中的溶解度选择合适的溶剂配制储备液；一旦配成溶液，请分装保存，避免反复冻融造成的产品失效。
储备液的保存方式和期限：-80°C, 6 months; -20°C, 1 month (sealed storage, away from moisture and light)。-80°C 储存时，请在 6 个月内使用，-20°C 储存时，请在 1 个月内使用。

• [1]. Wang XJ, et al. Newly synthesized bis-benzimidazole derivatives exerting anti-tumor activity through inductionof apoptosis and autophagy. Bioorg Med Chem Lett. 2012 Oct 1;22(19):6297-300.

  [2]. Stolić I, et al. Synthesis, DNA/RNA affinity and antitumour activity of new aromatic diamidines linked by 3,4-ethylenedioxythiophene. Eur J Med Chem. 2011 Feb;46(2):743-55.

Hoechst 33258 is prepared as stock solutions in highly pure water. Working solutions in a concentration range of 10^-3-10^-6 mol/dm³ are prepared prior to testing. Cytotoxic effects of Hoechst 33258 on tested cell lines are determined by the MTT assay. Cells are seeded in 96 micro well flat bottom plates at a concentration of 2×10⁴ cells/mL and left overnight in the CO₂ incubator allowing them to attach to the plate surface. Growing medium is replaced with compound supplemented or control medium and incubated for 72 h. Fresh medium with 5 mg/mL of MTT is added onto cells and incubated for 4 h at 37°C. Upon media removal, water insoluble MTT-formazan crystals formed inside the living cells are dissolved in DMSO and the absorbance at 570 nm proportional to the number of living cells is measured on an Elisa Microplate Reader. All experiments are performed at least three times in triplicates.The GI₅₀ value, defined as the compound concentration (μM) leading to cellular growth inhibition by 50%, is calculated and used as a parameter to compare cytotoxicity among the compounds^[2].

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

• [1]. Wang XJ, et al. Newly synthesized bis-benzimidazole derivatives exerting anti-tumor activity through inductionof apoptosis and autophagy. Bioorg Med Chem Lett. 2012 Oct 1;22(19):6297-300.

  [2]. Stolić I, et al. Synthesis, DNA/RNA affinity and antitumour activity of new aromatic diamidines linked by 3,4-ethylenedioxythiophene. Eur J Med Chem. 2011 Feb;46(2):743-55.