Short Poster Lecture
Dopamine, which is mostly known as a neurotransmitter, is a small molecule that mimics the adhesive component, L-DOPA, of marine mussels with the structure of catecholamine. Dopamine can spontaneously polymerize to form polydopamine (PDA) in a mild basic environment (ph=8.5)1. PDA binds virtually to all type of surfaces and it offers a platform for post-modification (i.e. electroless metallization or conjugation of organic components). It's an environmental friendly reaction involving a few steps.
In this work, we have functionalized with PDA the surface of different substrates (stainless steel, Ti6Al4V, 45S5 Bioglass® and novel silicate bioactive glass (so-called BG1)). In addition, we have further incorporated copper (Cu) nanoparticles, which would confer not only an antibacterial behavior to the surface, but also enhance the angiogenic properties of the sample. We have characterized the surfaces by terms of zeta-potential, tape test and nanoindentation test . Additionally, samples were characterized by terms of SEM-EDS, XRD, FTIR and Raman spectroscopy.
Results show the successful achievement of PDA deposition, independently from the substrate. From zeta potential measurements, we have hypothesized that the exposed chemical groups of polydopamine are different depending on the substrate. Tape test and nanoindentation test show that the behavior of the polymer is different depending on the substrate, as well. SEM-EDS confirmed the deposition of Cu onto PDA-coated surfaces. Cu nanoparticles provoke a SERS (Surface-Enhanced Raman Scattering) effect.
Further studies to characterize the biocompatibility of the samples and the dual effect of PDA and Cu ions are being conducted.
