One-pot green synthesis of mussel-inspired myoglobin–gold nanoparticles–polydopamine–graphene polymeric bionanocomposite for biosensor application

Adsorption behavior of organic pollutants and metals on micro/nanoplastics in the aquatic environment

Plastic debris becomes currently a ubiquitous environmental pollutant and is susceptible to contamination by many other pollutants, including aqueous metals and organic matter. This review summarizes the effects of environmental factors on the properties and sorption behavior of microplastics, presents a further discussion on the fate of microplastics adsorption on contaminants, and critically discusses the mechanism of sorption behaviors between micro/nanoplastics and normal contaminants. Previous references indicated that the hydrophobicity and particle sizes of microplastics were the dominant influence factors for virgin plastic debris adsorption, whereas for aged microplastics, hydrogen bonding, hydrophilicity and increasing specific surface ratio affected the adsorption behavior. The effects of pH and salinity always influence the sorption conditions by changing the charge state of microplastics and contaminants and causing competing adsorption. In addition, the existence of microplastics affects biotoxicity, increases the dissolved organic matter in the environment, and influences carbon cycling. The knowledge is fundamental to the assessment of potential risks posed by microplastics to organisms from human beings to the entire environment.

The control of the adsorption of bovine serum albumin on mercaptan-modified gold thin films investigated by SERS spectroscopy

Nanostructured gold thin films were built from deposition of colloidal gold nanoparticles on silanized glass slides, and used to study the adsorption of bovine serum albumin (BSA) after chemical treatment of gold surface with the mercaptans 2-mercaptoethanol, 3-mercaptoproprionic acid, 1,3-propanedithiol and 1-propanethiol. Surface-enhanced Raman scattering (SERS) spectroscopy was used for investigating the chemical interactions of BSA with the modified gold surfaces. In the presence of the surface modifier 2-mercaptoethanol, a promoter of hydrogen bonds, the stable interactions among BSA and gold surfaces led to high reproducibility of the SERS spectral pattern in the most monitored points of the mapped surface. The vibrational assignment endorsed the assumption that lysine residue, majority present in the molecular structure, were the principal anchor site of BSA involved in the interactions with 2-mercaptoethanol-modified gold surface.