We can't find the internet
Attempting to reconnect
Something went wrong!
Hang in there while we get back on track
Benzo[a]pyrene and heavy metal ion adsorption on nanoplastics regulated by humic acid: Cooperation/competition mechanisms revealed by molecular dynamics simulations
AI summary Read the abstract
Researchers used molecular dynamics simulations to investigate how humic acid regulates the adsorption of the carcinogen benzo[a]pyrene and copper ions onto nanoplastics. They found that polystyrene nanoplastics had the highest capacity for adsorbing the carcinogen, while humic acid formed eco-coronas on nanoplastic surfaces that both hindered direct pollutant binding and created new binding sites for metal ions. The study reveals cooperation and competition mechanisms that govern how nanoplastics interact with multiple contaminants in aquatic environments.
Nanoplastics adsorb pollutants and organic matter to aggravate or alleviate impact to the eco-environment and human health. However, the interaction mechanisms remain unclear and difficult to study using current experimental techniques. By means of molecular dynamics simulation, here we investigate adsorption of benzo[a]pyrene (BaP) and heavy metal ions (Cu) on nanoplastics of different materials and surface charges regulated by humic acid (HA). Among considered materials, polystyrene shows the highest capacity of adsorbing BaPs via forming sandwiched π-stacking structures with benzene rings. Driven by hydrophobic, electrostatic and hydrogen bonding interactions, HAs spontaneously aggregate into micelle-like structures with hydrophobic core and charged exterior accessible to BaPs and Cu, respectively. Cationic and neutral nanoplastics adsorb more HAs to form eco-coronas, which modulate BaP and Cu adsorption via following cooperation/competition mechanisms. On one hand, the direct binding of BaPs to nanoplastics is hindered by HAs through BaP encapsulation plus competitive adsorption. On the other hand, adsorbed HAs expose carboxyl groups to offer rich binding sites to promote Cu adsorption on neutral and cationic nanoplastics, while unbound HAs compete with anionic nanoplastics to inhibit Cu adsorption. These results provide molecular level insights into transport, transformation and accessibility of nanoplastics with coexisting contaminants in the aqueous environment.
More Papers Like This
Interfacial interactions of humic acids with polystyrene nano-plastics in aqueous/ionic environments: a molecular dynamics exploration
AI summary Read the abstract
Researchers used molecular dynamics simulations to investigate how humic acid molecules interact with carboxylated polystyrene nanoplastics in water, finding that humic substances form an eco-corona on the nanoplastic surface that alters its environmental behavior and potential toxicity.
Cation-π mechanism promotes the adsorption of humic acid on polystyrene nanoplastics to differently affect their aggregation: Evidence from experimental characterization and DFT calculation
AI summary Read the abstract
Researchers investigated how humic acid and metal ions in natural lake water affect the clumping behavior of polystyrene nanoplastics, finding that a cation-π bonding mechanism — where metal ions bridge humic acid molecules onto the nanoplastic surface — governs whether particles aggregate or remain dispersed, with major implications for their environmental persistence and toxicity.
Effects of Polymer Morphology on Humic Acid Adsorption onto Model Microplastics and Nanoplastics
AI summary Read the abstract
Computer simulations modeled how natural organic material (humic acid) sticks to tiny plastic particles with different surface structures. Smooth, ordered plastic surfaces attracted humic acid through flat contact points, while disordered surfaces created stronger or weaker binding depending on the plastic type, showing that particle surface structure affects how coatings form on microplastics.
Nanoplastic adsorption characteristics of bisphenol A: The roles of pH, metal ions, and suspended sediments
AI summary Read the abstract
Researchers found that nanoplastics adsorb bisphenol A through electrostatic, pi-pi stacking, and hydrophobic interactions, with adsorption capacity influenced by pH, competing metal ions, and suspended sediments, highlighting nanoplastics as vectors for BPA transport in aquatic environments.
Adsorption of typical natural organic matter on microplastics in aqueous solution: Kinetics, isotherm, influence factors and mechanism
AI summary Read the abstract
Researchers investigated humic acid adsorption onto PVC and PS microplastics, finding that pH, ion species, particle size, and surfactants significantly influenced adsorption capacity through mechanisms including halogen bonding, hydrogen bonding, and pi-pi interactions.
Research digests by email
When a large batch of papers lands in the Atlas, we read through it and send a short write-up of what stood out.