Poly-d-Lysine (PDL) Stock (1 mg/mL)

• 1. Resuspend poly-d-lysine (PDL; Sigma-Aldrich P6407; molecular weight 70–150 kDa) at 1 mg/mL in borate buffer by combining 50 mg of PDL and 50 mL of 0.15 m boric acid (pH 8.4).

• 2. Filter to sterilize, and then aliquot (e.g., 100 µL/tube). Store aliquots at −20°C.

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