In this study, the adsorption behavior of Cu(II) and Pb(II) on the biofilm-developed polystyrene (PS) microplastics (MPs) was compared with the virgin PS (V-PS) and UV-aged PS (UV-PS). The results demonstrated that the biofilm could enhance the adsorption abilities onto MPs more than UV radiation. The intra-particle diffusion model suggested that the adsorption on V-PS was dominated by intra-particle diffusion, while the adsorption rate was controlled by the binding diffusion on UV-PS and biofilm-developed PS (Bio-PS). Compared with the V-PS and UV-PS, the Bio-PS showed the largest adsorption capacity based on the Freundlich isotherm model, which indicated that the adsorption of heavy metals onto Bio-PS was multilayer and heterogeneous. The adsorption mechanism of Bio-PS contained physical adsorption, chemisorption, and biosorption. These Bio-PS adsorption types participated in both oxygen and nitrogen groups. Based on the 16S rRNA analysis, the diversity of the microbial community with biofilm changed to a certain extent after the adsorption of heavy metals. Furthermore, the stress of lead (Pb) adsorption had a higher impact on the microbial community distribution and the PS biofilm. This study illustrated how the formation of biofilms can highly affect the adsorption behavior of MPs as well as the microbial community of MPs.

在这项研究中，Cu(II) 和 Pb(II) 在生物膜形成的聚苯乙烯 (PS) 微塑料 (MPs) 上的吸附行为与原始 PS (V-PS) 和紫外线老化 PS (UV-PS) 进行了比较。 ）。结果表明，生物膜比紫外线辐射更能增强对 MPs 的吸附能力。颗粒内扩散模型表明，V-PS 上的吸附以颗粒内扩散为主，而吸附速率受 UV-PS 和生物膜形成的 PS (Bio-PS) 上的结合扩散控制。与V-PS和UV-PS相比，基于Freundlich等温线模型的Bio-PS表现出最大的吸附容量，这表明Bio-PS对重金属的吸附是多层且不均匀的。Bio-PS的吸附机理包括物理吸附、化学吸附和生物吸附。这些 Bio-PS 吸附类型参与了氧和氮基团。16S rRNA分析表明，吸附重金属后，具有生物膜的微生物群落多样性发生了一定程度的变化。此外，铅（Pb）吸附应力对微生物群落分布和PS生物膜的影响更大。该研究说明了生物膜的形成如何高度影响 MPs 的吸附行为以及 MPs 的微生物群落。