In order to address a global issue in regard to the shortage of drinking water resources, reverse osmosis (RO) processes have been considerably attended to provide people with high-quality fresh water. In spite of many efforts carried out for preparation of efficient RO membranes, fouling/biofouling remains as a significant challenge. In this study, antibacterial polyamide thin film composite (PA-TFC) decorated with hydrophilic polyrhodanine (PRh) nanoparticles was fabricated through a novel route of direct filtration method. This method is a facile technique for modification of the membrane surface, in particular, for recovery of the membrane antibacterial agent which is lost during the process. The synthesized membranes were studied for morphology, surface functional groups, hydrophilicity, and surface roughness via FESEM, FTIR, contact angle, and AFM analysis. Both diffusion inhibition zone and colony formation unit tests exhibited excellent biocidal activity of the PRh loaded membranes against Gram-negative Escherichia coli and Gram-positive Staphylococcus aureus strains. Moreover, the best fouling resistance was assigned to PA-TFC membrane decorated with 0.5%wt. PRh, and PA-TFC membrane modified with 0.75%wt. PRh revealed the best salt rejection ability. (C) 2019 Institution of Chemical Engineers. Published by Elsevier B.V. All rights reserved.