Poly-L-lysine（MW：30000-70000）

Poly-lysine, a cationic amino acid polymer, possesses the ability to bind to negatively charged molecules such as DNA, red blood cell membrane, and proteins. Its role as a non-specific cell adhesion factor facilitates the attachment of cells to solid surfaces. This occurs through an enhancement of electrostatic interactions between negatively charged ions on the cell membrane surface and the surface of the solid substrate, such as glass slides or cell culture dishes. By adsorbing onto the culture surface, poly-lysine increases the number of cation binding sites available for cell adhesion. The molecular weight of poly-lysine affects its viscosity, with lower molecular weight corresponding to lower viscosity. Conversely, higher molecular weight leads to higher viscosity, thereby providing more adhesive sites. For promoting cell adhesion to solid substrates, poly-lysine with a molecular weight exceeding 30,000 is recommended. Poly-lysine has two commonly found subtypes, D- and L-types. Due to its non-specific cell adhesion nature, both subtypes can be utilized as coating agents for solid substrates, facilitating the growth of adherent cells in cell culture applications. Specifically, this product refers to Poly-L-lysine with a molecular weight ranging from 30,000 to 70,000, suitable for cell culture purposes. When used in a cell culture medium, the suggested dosage is approximately 0.5ml to 1.0ml of a 0.1mg/ml poly-lysine solution for a 25cm2 culture plate.

1. To prepare a storage solution, you will need to dissolve 25mg of powder in 5ml of sterile deionized water. To ensure sterilization, pass this solution through a 0.2μm low-protein adsorption filter. This will result in a 5mg/ml poly-L-lysine stock solution that can be directly used for cell culture. To avoid contamination from multiple uses, it is recommended to divide the storage solution into single-use amounts and store them at either 4°C or -20°C. The solution can remain valid for at least one year.
2. In order to coat the substrate for cell culture, the poly-L-lysine concentration needs to be optimized based on the specific cell lines and applications. Follow these general steps:
a. Dilute the 5mg/ml poly-L-lysine stock solution with sterile tissue culture grade water or PBS to obtain the desired coating concentration for your specific experimental system. For instance, the commonly used coating concentration for a petri dish/plate is 0.1mg/ml, which requires a 50-fold dilution of the stock solution.
b. Under aseptic conditions, apply 0.5ml-1.0ml of the diluted solution per 25cm2 of the cell culture plate. Gently shake the plate to ensure the entire surface is covered.
c. After 5 minutes, remove the excess solution from the plate using a pipette or other appropriate instrument. Clean the plate's surface with sterile tissue culture grade water or PBS. Please note that in certain cases, the coating process may take 1 to 2 hours or even overnight, depending on the specific requirements.
d. Once the coated plate has been air-dried for at least 2 hours, it can be used for cell culture.
Note: If you need to coat glassware or slides under sterile conditions, they can be sterilized using γ-ray irradiation instead of autoclaving.
3. For histological research, specifically for coating glass slides, a recommended concentration of 0.1% (w/v) poly-L-lysine solution is used. After treating the glass slide with the appropriate concentration of poly-L-lysine solution for 5 minutes, clean and dry the slide overnight at room temperature, or use an oven at approximately 60°C for 1 hour to expedite the drying process. It is important to store this working solution in a plastic bottle at 4°C, and it should be used for no more than four times to ensure its effectiveness.

Desiccate at -20°C for 3 years

1. In some cell culture applications, some cells will digest and absorb poly-L-lysine. Excessive intake of poly-L-lysine will cause certain cytotoxicity. Therefore, in this case, it is recommended to use Poly-D-lysine, such as Poly-D-lysine (Mw/30,000-70,000).2. This product is provided in the form of hydrobromic acid (HBr), and each lysine residue contains about one HBr. The presence of HBr allows polylysine to dissolve in neutral buffer and remove salt ions through dialysis.3. For your safety and health, please wear lab coats and disposable gloves for operation.

Poly-L-lysine (Mw 30,000-70,000)

White Solid

soluble in water