Effect of CNT/PDMS Nanocomposites on the Dynamics of Pioneer Bacterial Communities in the Natural Biofilms of Seawater

Abstract

In this study, the antifouling (AF) performance of different carbon nanotubes (CNTs)-modified polydimethylsiloxane (PDMS) nanocomposites (PCs) was examined directly in the natural seawater, and further analyzed using the Multidimensional Scale Analyses (MDS) method. The early-adherent bacterial communities in the natural biofilms adhering to different PC surfaces were investigated using the single-stranded conformation polymorphism (SSCP) technique. The PCs demonstrated differences and reinforced AF properties in the field, and they were prone to clustering according to the discrepancies within different CNT fillers. Furthermore, most PC surfaces only demonstrated weak modulating effects on the biological colonization and successional process of the early bacterial communities in natural biofilms, indicating that the presence of the early colonized prokaryotic microbes would be one of the primary causes of colonization and deterioration of the PCs. C6 coating seems to be promising for marine AF applications, since it has a strong perturbation effect on pioneer prokaryotic colonization.

Keywords: antifouling coatings; biofouling; multidimensional scale analysis; natural biofilms; polydimethylsiloxane; single-stranded conformation polymorphism.

Figure 1

Location of the immersion sites for the field studies: Small Stone Island in the Western Port, Weihai, China.

Figure 2

Appearances of various PDMS-based panels after static immersion for two months (April–June, 2015).

Figure 3

Clustering patterns of the antifouling (AF) capacity of the PDMS-based nanocomposites based on the MDS analysis.

Figure 4

SSCP fingerprints of pioneer bacterial communities in the natural biofilms developed on different PDMS-based composite surfaces with different exposure times.

Figure 5

Clustering analysis of pioneer bacterial communities on different PDMS-based material surfaces based on the MDS method. PP0, PM, PH and PC represent the pioneer bacterial communities adhering to the surfaces of P0 coating, M1–M6 coating, coating H1–H6 coating and C1–C6 coating, respectively.

Figure 6

The comparison of the diversity indices, (a–c) Shannon diversity index, (d–f) species richness, (g–i) Simpson index of pioneer bacterial communities on different PDMS-based material surfaces.