Abstract

NanoToxChip: A Novel Microfluidic Chip for In-vivo Assessment of Nanoplastics Toxicity

Preyojon Dey, PhD Candidate, Florida International University

Nanoplastics (NPs) are emerging marine contaminants that are capable of disrupting marine ecosystems, migrating up the food chain, and reaching humans. This study describes a novel microfluidic device for assessing in-vivo NP toxicity. The chip can autonomously control waterborne and foodborne exposure of NPs to measure the effect of various exposure routes. Conventional NP toxicity assessment utilizes well plates, beakers, and fish tanks with static exposure conditions, which increases nanoparticle agglomeration, reduces bioavailability, reduces dissolved oxygen for test animals, and increases fouling. Large media volumes make it challenging to maintain uniform environment, which influences nanoparticle agglomeration, uptake, and even organisms. Conventional methods also necessitate human intervention to transport and immobilize the animal for study, which may impair the animal's physiological and neurological processes and limit data gathering to specific time intervals. The microfluidic device utilizes a continuous flow of NP-spiked water, maintains uniform environmental conditions, provides real-time, in-situ data on metabolism via an on-chip optical oxygen sensor and NP bioaccumulation in test animals via fluorescence microscopy. This study utilized Coryphaena hippurus (predator) and Brachionus plicatilis (prey) as animal models and two different sized and fluorescent colored polystyrene nanoplastics as model NPs. The model animals demonstrated substantial bioaccumulation of these NPs and altered oxygen consumption (energy metabolism).