Binding and its effects of micro/nano-particulate emerging contaminants with biomacromolecules

The rapid advancement of micro and nanotechnology over the past five decades has led to the development of diverse micro and nano-materials, widely utilized in various sectors such as agriculture, medicine, food, and textiles. By 2022, the global market size for these materials had surpassed 55 billion US dollars, with TiO2-NPs, SiO2-NPs, AgNPs, and ZnNPs being among the most widely employed nano-materials. However, the production and transportation of micro- and nano-products inevitably result in the release of particulate matter into the environment. Meanwhile, the decomposition of plastic debris into micro- and nano-plastics poses significant threats to ecological systems and human health. In recent years, micro- and nano-particulate matter has been detected in global environmental media, with its environmental impact and synergistic effects with other pollutants garnering substantial attention and emerging as a focal point of current research. Biomacromolecules, including nucleic acids, proteins, and polysaccharides, are crucial bio-molecules that play a vital role in the biological processes of living entities. Pollutants frequently cause changes in the structure and function of biomacromolecules including DNA and proteins, which might result in possible health hazards. Therefore, it is essential to study the mechanisms and impacts of the interaction between contaminants and biomacromolecules in order to understand the potential health risks they provide. To elucidate the potential detrimental effects of micro-nano particulate pollutants on human health and their underlying mechanisms, as well as to develop effective prevention and control strategies, researchers have recently focused on the interaction between these pollutants and biomacromolecules. Significant progress has been made in this field, revealing that micro- and nano-particulate pollutants bind to biomacromolecules through non-covalent interactions, including inter-molecular hydrophobic interactions, electrostatic interactions, π-π interactions, hydrogen bonding, and van der Waals forces. The binding processes are significantly influenced by the pollutants’ characteristic properties (such as spatial configuration, shape, surface chemistry, and surface charge distribution) and environmental factors (including ionic strength, pH, and buffer solution concentration). The binding of micro- and nano-particulate pollutants to biomacromolecules induces conformational changes in DNA and proteins, mediating alterations in cellular properties and affecting cell differentiation and proliferation. When certain micro-particles and nanoparticles bind to plasmids, the migration of antibiotic resistance genes (ARGs) is promoted, although this promotion is regulated by particle concentrations. At high concentrations, some micro-particles and nanoparticles, such as metal oxide nanoparticles, exhibit strong aggregation, consequently inhibiting ARG migration. Furthermore, the binding of intracellular biomacromolecules with micro- and nano-particulate pollutants has been associated with long-term or chronic diseases. This review comprehensively examines the binding effects of micro- and nano-particulate pollutants with biomacromolecules from the perspectives of “action” and “effects”. Despite these advancements, most relevant studies have primarily focused on the binding between micro- and nano-particulate pollutants and DNA and proteins, with limited attention given to their interactions with polysaccharide molecules. Future research should explore the interactions between micro- and nano-particulate pollutants and polysaccharides, as well as their underlying mechanisms. Additionally, studies on the molecular ecological effects of micro- and nano-particulate pollutants have primarily concentrated on a limited number of pollutants, such as micro-plastics, carbon-based nanoparticles, and metal-based and metal-oxide nanoparticles. The binding effects have largely focused on the impact of bio-molecule interactions on the horizontal transfer of ARGs. Therefore, future investigations should encompass a broader range of micro- and nano-particulate pollutants and expand the scope of their binding effects with biomacromolecules.