The Impact of Poly (Propylene Imine) Dendrimer-Grafted to Poly (lactic Acid) Membrane Surfaces on Water Adsorption

The major objective of this research was to modify Poly (L-lactic acid) (PLLA) membrane surfaces with second generations of poly (propylene imine) dendrimer (PPI-G2). PLLA is a popular material in many applications due to the biodegradable and biocompatible properties; however, its poor hydrophilicity limited its applications in many cases. In the present study, PLLA membranes were fabricated by a solution casting method and their surfaces were subsequently modified first by NaOH hydrolysis and plasma treatment to produce carboxylic acid group on the surface membranes. Then, the carboxylic acid surfaces were activated by 1-ethyl-3-(3-dimethylami-nopropyl) carbodiimide (EDC) as a heterobifunctional cross-linker promoted the coupling COOH groups on modified PLLA membrane and NH2 groups of PPI-G2. The membrane surface resulting from each reaction step was analyzed using FTIR spectroscopy and contact angle measurement. Result showed that the PPI-grafted surfaces showed reduced the hydrophobicity of the membranes. Since this study demonstrates that covalently bound PPI dendrimers can modulate the adsorption response, this approach has significant potential for the development of antibacterial and drug adsorption biomaterial surfaces.