Influence of Silver Nanoparticle–Based Coating on Calcareous Rock Surfaces on Microbial Biofilm Colonization in Intertidal Environments in Campeche, Mexico

Abstract

The influence of silver nanoparticles (AgNPs) on microbial biofilm colonization on natural calcareous rocks was studied in the Campeche marine intertidal environment in southeast Mexico. The biofilm formation was assessed by color spectrophotometer measurements represented in the CIELAB color space, digital image analysis, confocal laser scanning microscopy, biochemical biomarkers, and enumeration of morphologically characterized cells by FlowCAM®. Coupons were exposed with or without polydimethylsiloxane (PDMS) coatings and without or with various concentrations of AgNPs. Initial colonizers on all surfaces were diatoms of the species Coscinodiscus centralis. After 60 days’ exposure to the marine environment, other genera of microalgae and cyanobacteria were observed. Biofilm formation was reduced on all coated coupons to a greater or lesser extent than bare rock, indicating that these nanomaterials’ presence altered biofilms’ formation on calcareous rock negatively on microbial communities’ essentials for ecosystem health.