Poly-D-lysine is a positively charged amino acid polymer with approximately one HBr per lysine residue. The hydrobromide allows the poly-D-lysine to be in a crystalline form soluble in water. A small amount of product may be found in the ß structure because the HBr interferes with hydrogen bonding between amino and either the carboxyl groups or N or O containing moieties.
Poly-D-lysine polymers can be used in preparing surfaces for cell attachment. The D-lysine polymers can also be used with cells that digest poly-L-lysine polymers and cause an excessive uptake of L-lysine.
This product is recommended as a cell culture substratum when using 0.5 - 1.0 mL of a 0.1 mg/mL solution to coat 25 cm2. Lower molecular weight versions of the product are less viscous, but high more molecular weight versions provide more attachment sites per molecule.