Methyl blue is a triaminotriphenylmethane dye. It is used as an antiseptic dye in the polychrome staining method and has applications in histological and microbiological staining solutions.

Instructions
1. Solution configuration
1. Mother liquor configuration: Dissolve Methyl Blue in an appropriate solvent (such as water or PBS), usually at a concentration of 1-10mM.
2. Configuration of working liquid: When using, dilute the mother liquid with PBS/H2O/DMEM to a working liquid of a certain concentration, and dilute it according to the actual situation, such as 5μM.
1. Antibacterial staining
Experimental steps:
1. Prepare the sample: Apply the bacteria or microorganism sample to be stained onto the slide, and then air-dry and fix it (such as using methanol).
2. Staining: Add Methyl Blue solution dropwise to the sample, and the staining time is usually 5-10 minutes.
3. Clean and observe: Use distilled water to clean the sample to remove excess dye. Use a microscope to observe the staining effect of bacteria or microorganisms.
2. Histological staining
Experimental steps:
1. Staining sections: Immerse the tissue sections in Methyl Blue working fluid, the staining time is 5-15 minutes, and the specific time is adjusted according to the tissue type and staining intensity.
2. Clean and seal: Wash the sections with water or PBS to remove unbound dye. After the tablets were sealed with a mounting medium, use a microscope to observe the staining effect.
III. Research on photodegradation of catalysts
Experimental steps:
1. Reaction mixture: Mix the Methyl Blue working liquid with a catalyst (such as a photocatalyst or photosensitization catalyst).
2. Light reaction: Under light conditions (such as ultraviolet light or visible light irradiation), let the reaction mixture react for a certain period of time (usually 30 minutes to several hours).
3. Analyze the degradation effect: Use a spectrophotometer or high-performance liquid chromatography (HPLC) to monitor the photodegradation of Methyl Blue to evaluate the degradation effect of the catalyst.

The above information is based on published literature. Experimental procedures should be appropriately modified to meet specific research demands.

H2O: 19 mg/mL (23.76 mM), Sonication is recommended.