A simple procedure for coating surfaces

Originally polymers of L-lysine were used but because this is the metabolically active form of the amino acid, some workers prefer to use poly-D-lysine. A simple procedure for coating surfaces follows. 

Select the required molecular weight range of poly-lysine, i.e. 30 000-70 000, 70 000-150 000 or over 300 000. The charge density of the molecules increases with molecular weight, so selection should be based on the degree of binding required. 

Add sterile water to the lyophilized poly-lysine to give a final concentration of 

1 mg mH. Leave at room temperature until completely dissolved, which should be within a few minutes. Store the solution at 4 C. 

Add the solution to culture flasks or dishes using 0.5-1 ml per 20-25 cm surface area. 

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