Small Intestinal Biofilms Show Charge-Dependent Interactions with Positive Polystyrene Nanoplastics

Authors: Maud Boisson, Shirmin Islam, Gretchen Mahler, Cláudia N.H. Marques

Field of Study: Biological Sciences

Program Affiliation: Binghamton Biofilm Research Center

Faculty Mentors: Cláudia N.H. Marques, Shirmin Islam

Easel: 23

Timeslot: Morning

Abstract: Commensal bacteria present in the small intestine play an important role in barrier integrity, immune signaling, and mucosal balance. Nanoplastics are now ubiquitous and have entered the food chain; however, their effect on the gut homeostasis is still unknown. This work focused on Lacticaseibacillus rhamnosus, a key bacterial species of the small intestine, and studied the effect of different charges of polystyrene nanoplastics (NPLs) at a 1 mg/L concentration on biofilm growth and development. Bacterial growth was measured by absorbance (595 nm), while biofilm development and biomass were determined using viable counts and crystal violet assays. The NPL interactions were observed using epifluorescence microscopy. Overall, it was found that at a physiological concentration (1 mg/L), NPLs do not significantly affect bacterial viability or biofilm growth.