2.3.1. Synthesis of Dopamine-BiBB

For the chemical modification of dopamine hydrochloride, the procedure reported in the literature by Liu et al. was followed (Figure S3 in the Supporting Information).⁴⁰ Dopamine hydrochloride (2 g, 10.5 mmol) was dissolved in 200 mL DMF inside a three-neck round-bottom flask equipped with a condenser. Nitrogen was bubbled in the solution for 30 min. Then, 748 μL TEA (5.3 mmol) and 652 μL BiBB (5.3 mmol) were added while stirring. The solution was stirred under nitrogen atmosphere at room temperature for 24h.