It is mainly composed of fluorescein, Evans blue, potassium hydroxide, propanetriol and deionized water. Fungal cell wall contains more chitin and cellulose and other β-polysaccharides, which can be combined with fluorescein to form a complex, which can be seen under a fluorescence microscope to produce fluorescence under specific excitation light. In addition, the product can detect Pneumocystis carinii cysts, parasites (e.g., Plasmodium), and various types of geographically variable fungal mycelium keratin, collagen, and elastic fibers, which can be clearly differentiated and detected by fluorescent labeling of the structural boundaries of these substances.