Release of Engineered Nanomaterials from Polymer Nanocomposites: Diffusion, Dissolution, and Desorption

Abstract

Polymer nanocomposites-polymer-based materials that incorporate filler elements possessing at least one dimension in the nanometer range-are increasingly being developed for commercial applications ranging from building infrastructure to food packaging to biomedical devices and implants. Despite a wide range of intended applications, it is also important to understand the potential for exposure to these nanofillers, which could be released during routine use or abuse of these materials, so it can be determined whether they pose a risk to human health or the environment. This article is the first in a series of two that review the state of the science regarding the release of engineered nanomaterials (ENMs) from polymer nanocomposites. Two ENM release paradigms are considered in this series: the release of ENMs via passive diffusion, desorption, and dissolution into external liquid media and release of ENMs assisted by matrix degradation. The present article focuses primarily on the first paradigm and includes (1) an overview of basic interactions between polymers and liquid environments and a brief summary of diffusion physics as they apply to polymeric materials; (2) a summary of both experimental and theoretical methods to assess contaminant release (including ENMs) from polymers by diffusion, dissolution, and desorption; and (3) a thorough, critical review of the associated body of peer-reviewed literature on ENM release by these mechanisms. A short outlook section on knowledge gaps and future research needs is also provided.

Review on the Processing and Properties of Polymer Nanocomposites and Nanocoatings and Their Applications in the Packaging, Automotive and Solar Energy Fields

“…However, detection of possibly migrated nanomaterials in complex matrices, like food or food simulants, is quite challenging, wherefore the results of migration studies are often not consistent and sometimes even contradictory. A comprehensive overview on this topic can be found elsewhere [324,325,326]. …”

Environmental release of core–shell semiconductor nanocrystals from free-standing polymer nanocomposite films

“…44 d This value reflects the mass of each element divided by the summed mass of all four analyzed elements in an analyzed quantity of material, as determined by ICP-AES analysis of QDs after microwave digestion. Compositional analysis data reported here represents the mean values ( n = 3); standard deviations are provided in the ESI section.…”

In vitro and in vivo drug release behavior and osteogenic potential of a composite scaffold based on poly(ε-caprolactone)-block-poly(lactic-co-glycolic acid) and β-tricalcium phosphate

“…47 RFP is hydrophobic and its solubility in water is limited. Those RFP molecules embedded inside polymeric matrixes would be released via steps of water molecules interpenetration and RFP diffusion out, in which, the physiochemical features of polymeric matrix played important roles in regulating release behaviors.…”