Micro-fabricated polydimethyl siloxane (PDMS) surfaces regulate the development of marine microbial biofilm communities

Abstract

This study explored an antifouling (AF) concept based on deployment of microfabricated polydimethyl siloxane (PDMS) surfaces with 1–10 μm periodicity corrugated topographies in temperate marine waters. The effect of the surfaces on the development of microbial biofilms over 28 days and during different seasons, including both summer and winter, was examined using confocal laser scanning microscopy (CLSM) as well as terminal restriction fragment (T-RF) analysis for phylogenetic fingerprinting. The microscale topography significantly impacted biofilm development by altering the attachment pattern and reducing microcolony formation on the 1, 2 and 4 μm PDMS surfaces. Also, field deployments over 28 days showed a significant reduction in biovolume on the 4 and 10 μm PDMS surfaces despite altered environmental conditions. The microfabricated PDMS surfaces further significantly impacted on the community composition of the biofilms, as revealed by changes in T-RF profiles, at different stages of development. Moreover, altered biofilm resistance was demonstrated by exposing pre-established biofilms on 10 μm micro-fabricated surfaces to enhanced flagellate predation by a heterotrophic protist, Rhynchomonas nasuta. Pronounced changes in the overall marine microbial biofilm development as well as community composition warrant exploring substratum modification for marine AF applications.