Searching for novel membrane chemistries: Producing a large library from a single graft monomer at high throughput

Glycidyl methacrylate (GMA) was grafted on poly(ether sulfone) (PES) membranes via photo-initiated graft polymerization (PGP). 25 amine monomers were introduced at 90 °C for 12 h to facilitate the epoxy ring opening reaction on GMA grafts. Our high throughput platform (HTP) approach was used to test and screen for desired surface characteristics. Analysis of the fouling index (ℜ, flux reduction upon static fouling), surface adsorption index (image, surface adhesion of protein) and sieving coefficient (S0, protein permeation upon dynamic fouling) were used as criteria of success. Bovine serum albumin (BSA) and lysozyme (LYS) at 1 mg mL−1 were used as model foulants. Six of the 25 grafted species were identified as “winners” by exhibiting lower ℜ and image (i.e. lower flux decline and protein adhesion on membrane surfaces, respectively) compared with GMA grafting alone (internal control) or with poly(ethylene glycol) (PEG) grafting. S0 was plotted against permeability in order to analyze the flux-selectivity behavior due to grafting and fouling. Diethanolamine was resistant both to BSA with ℜ = 0.31 ± 0.12, image, S0 = 0.86 ± 0.03, and LYS with ℜ = −1.96 ± 0.26, image and S0 = 0.65 ± 0.27. The conversion of the epoxy group by the reaction with amine was confirmed with the degree of grafting analysis using FTIR/ATR.