Thioflavine S (Direct Yellow 7) (Synonyms: Thioflavin S; Direct Yellow 7)

This plan only provides a guide, please modify it to meet your specific needs.

1. Prepare the dyeing solution:

(1) Cell experiment dye solution: Dissolve Thioflavine S in 1xPBS to obtain a dye working solution with a concentration of 0.1mg/ml;

(2) Tissue section staining solution: Dissolve Thioflavine S in 50% ethanol to obtain a dye working solution with a concentration of 0.125 mg/ml.

Note: Please adjust the concentration of the working fluid according to the actual situation and prepare it for use.

2. Cell staining

(1) Culture adherent cells on sterile coverslips;

(2) Remove the coverslip from the culture medium and wash 1-2 times with 1x PBS;

(3) Use 4% paraformaldehyde to fix the cells at room temperature for 20 minutes;

(4) Add 100 μL of dye working solution from one corner of the coverslip and shake gently to evenly cover all cells with the dye. Incubate at 37°C in the dark for 5-30 minutes. The optimal incubation time for different cells is different, please explore by yourself according to the specific experimental needs.

 (5) After the incubation, discard the dye working solution and wash the coverslip 1-2 times with 1x PBS.

3. Tissue section staining

(1) Thioflavine S is suitable for frozen section staining and paraffin section staining;

(2) Stain the processed sections in Thioflavine S tissue section stain for 3-10 minutes. Please explore the dyeing time yourself according to specific experimental needs;

(3) Rinse the sections twice in 50% ethanol and H₂O;

4. Microscope detection: The maximum excitation light and emission light wavelengths of Thioflavin S are 391/428nm respectively.

Precautions:

1) Fluorescent dyes all have quenching problems. Please avoid light as much as possible to slow down fluorescence quenching.

2) For your safety and health, please wear a lab coat and disposable gloves.

References:

[1]. Megan E McLellan,et al. In vivo imaging of reactive oxygen species specifically associated with thioflavine S-positive amyloid plaques by multiphoton microscopy. 2003 Mar 15;23(6):2212-7. doi: 10.1523/JNEUROSCI.23-06-02212.2003.

[2].Anyang Sun, Xuan V Nguyen, Guoying Bing.Comparative analysis of an improved thioflavin-s stain, Gallyas silver stain, and immunohistochemistry for neurofibrillary tangle demonstration on the same sections. 2002 Apr;50(4):463-72. doi: 10.1177/002215540205000403.

[3].R Guntern, C Bouras, P R Hof, P G Vallet. An improved thioflavine S method for staining neurofibrillary tangles and senile plaques in Alzheimer's disease. 1992 Jan 15;48(1):8-10. doi: 10.1007/BF01923594.