Poly-D-lysine（5mg/ml），MW：150,000-300,000

Poly-Lysine is a versatile amino acid polymer that exhibits positive charges and has the ability to bind to DNA, erythrocyte membrane, or any negatively charged protein. Its main role is as a nonspecific cell adhesion factor, facilitating the attachment of cells to a solid substrate. The primary mechanism of action involves enhancing the electrostatic interaction between the negatively charged ions present on the cell membrane's surface and the solid substrate, such as a cell culture dish or glass slide. When polylysine is adsorbed onto the culture surface, it increases the number of cationic binding sites available for cell binding. The viscosity of polylysine is directly related to its molecular weight; lower molecular weight results in lower viscosity, while higher molecular weights lead to higher viscosity, providing more adhesion sites. The most suitable form for promoting cell adhesion to a solid matrix is polylysine with a molecular weight over 30,000. Poly-lysine has two common subtypes, namely D- and L-. Both subtypes can be used as coatings for solid matrices to foster cell adherent growth in cell culture, given their nonspecific binding properties. Poly-D-Lysine, with a molecular weight range of 30,000-70,000, proves excellent for cell culture purposes. As a cell culture substrate, the recommended dosage typically ranges from 0.1mg/mL of poly-lysine solution for 0.5mL-1.0mL on a 25cm2 culture plate.

1. Coating substrate for cell culture
To conduct effective cell-related coating experiments using polyD-lysine, it is crucial to optimize the coating conditions based on the specific cell lines and desired application. The process typically involves a set of general steps that need to be followed meticulously. These steps entail carefully selecting the coating solution, determining the right concentration level, and ensuring sufficient incubation time. Additionally, one must perform a thorough analysis of the coated substrate's surface properties and perform necessary quality checks to confirm the adherence of the cells to the coating. The success of these experiments depends largely on achieving optimal conditions, and it typically requires adjusting the parameters until the desired results are obtained.
To prepare the Poly-D-Lysine storage solution, simply add sterile tissue culture grade water or PBS to the diluted 5mg/mL concentration until it reaches the coating concentration that best suits your experimental needs. It's crucial to ensure accuracy in this step to achieve reliable and comparable results in your experiments.
The concentration for the standard petri dish/plate pack is typically diluted to 0.1mg/mL, which equates to a solution that is approximately 50 times stronger than the storage solution. It is important to maintain consistent dilution ratios to ensure accurate results in any laboratory setting.
Prepare the cell culture plates in a sterile environment, and apply a coating of 0.5mL-1.0mL/25cm2 evenly over the entire surface by gently shaking the bottom of the plate. It is essential to ensure complete coverage without any gaps to create an optimal environment for cell growth. Maintaining aseptic conditions throughout the process is crucial to prevent contamination and ensure successful cell culture.
After a period of 5 minutes had passed, a gun was used to remove the surface solution from the culture plate. After this, the surface of the culture plate was meticulously wiped down with sterile water or PBS of tissue culture grade quality. It should be noted that in some cases, additional steps may be required for cleaning.
The time required for completing the planking may vary between 1 to 2 hours and in some cases, it may even require overnight planking. The duration depends on several factors that are at play during the planking process.
4) Cell culture can be carried out after drying for at least 2h.
[Note] : If polylysine coated glassware or glass slides must be sterilized, γ-ray irradiation (rather than autoclapping) can be used
In addition to bacteria.
[Note] : If the coated surface is not smooth, you can use 1mM magnesium acetate pretreated glass slides for 2-3h, and then start to wrap after thoroughly cleaning.
Alternatively, the glass slides are washed with acid (hydrochloric or sulfuric acid), which results in a smooth coating of the polylysine solution.
2. Histological study (cover of glass slides)
Diluted 5mg/ mL Poly-D-Lysine storage solution to the most suitable coating concentration for your own experimental system using sterile tissue culture grade water or PBS.
0.1% (w/v) Poly-D-Lysine solution is generally recommended for the preparation of histological slides.
After the slides were treated with the corresponding concentration of polylysine solution for 5min, the slides were washed and dried overnight at room temperature or in an oven at approximately 60° C
Drying ~ 1 h.[Note] : The working solution is stored in a plastic bottle at 4° C, and the use times are limited to 4 times.

Store at -20°C

Poly-D-lysine Solution (5 mg/ml), Mw 150,000-300,000