Abstract
This thesis reports the fabrication and performance evaluation of a zwitterionic thin-film composite nanofiltration membrane based on poly (allyl methacrylate-r-sulfobetaine methacrylate) [P(AMA-r-SBMA)], synthesized by ARGET-ATRP and coated onto a commercial polyethersulfone substrate at 3.2 w/v%. In the binary NAD⁺/L-tryptophan system, the membrane achieved NAD⁺ rejection above 85% while L-tryptophan permeated freely, yielding selectivity values of 6.5–11 over 5 hours, with pH 9 producing the most stable performance. In a ternary peptide experiment, a clear size-based rejection hierarchy was demonstrated: BPC-157 (1,419 Da) at 80–83%, Leu-Enkephalin (556 Da) at 47–51%, and H-Trp-Tyr-OH (367 Da) at 2–3%. Antifouling performance against BSA yielded a flux recovery ratio of 93% compared to 38% for a commercial NP030 control, confirming the protein fouling resistance of the zwitterionic selective layer. UV-induced HOMP crosslinking produced unexpectedly elevated flux and loss of selectivity, attributed to incompatibility between the r-ZAC selective layer and the polyethersulfone substrate. Overall, the uncrosslinked membrane demonstrated reproducible size-based separation, stable flux, and strong antifouling resistance across all experimental conditions.
Date of publication
2026
Document Type
Thesis
Language
english
Persistent identifier
http://hdl.handle.net/10950/5137
Committee members
Dr. Zishu Cao, Dr. Carla Lacerda, Dr. Mohammad Biswas
Degree
Master of Science in Mechanical Engi
Recommended Citation
Phanos, Derick Asiedu, "FABRICATION OF ZWITTERIONIC MEMBRANES FOR BIOMOLECULE SEPARATION" (2026). Mechanical Engineering Theses. Paper 48.
http://hdl.handle.net/10950/5137