Advanced Compositional Analysis of Nanoparticle-polymer Composites Using Direct Fluorescence Imaging

Abstract

The fabrication of polymer-nanoparticle composites is extremely important in the development of many functional materials. Identifying the precise composition of these materials is essential, especially in the design of surface catalysts, where the surface concentration of the active component determines the activity of the material. Antimicrobial materials which utilize nanoparticles are a particular focus of this technology. Recently swell encapsulation has emerged as a technique for inserting antimicrobial nanoparticles into a host polymer matrix. Swell encapsulation provides the advantage of localizing the incorporation to the external surfaces of materials, which act as the active sites of these materials. However, quantification of this nanoparticle uptake is challenging. Previous studies explore the link between antimicrobial activity and surface concentration of the active component, but this is not directly visualized. Here we show a reliable method to monitor the incorporation of nanoparticles into a polymer host matrix via swell encapsulation. We show that the surface concentration of CdSe/ZnS nanoparticles can be accurately visualized through cross-sectional fluorescence imaging. Using this method, we can quantify the uptake of nanoparticles via swell encapsulation and measure the surface concentration of encapsulated particles, which is key in optimizing the activity of functional materials. Video LinkThe video component of this article can be found at

Covalently Attached Antimicrobial Surfaces Using BODIPY: Improving Efficiency and Effectiveness

“…Finally, there is the issue of material wastage by trapping it in the bulk of the polymer, away from the surface, where it cannot impact the microorganisms due to the short path length of any ROS generated within the polymeric matrix. 16,17 The covalent attachment of the most effective triarylmethane dyes (crystal violet) to the nanoparticle or polymeric material may surmount many of the aforementioned problems; however, synthetically, it is nontrivial and in cases where colocation with nanomaterials is desirable, it becomes difficult to ensure the nanoparticles are located at or near the surface. 18,19 Here, we have searched for known efficient triplet producing dyes that have a modular (easily modifiable) structure to allow for ease of covalent attachment and good ROS generation without nanomaterial incorporation.…”

“…Other cheaper nanomaterials have been explored with success, such as ZnO and Cu particles, ,, but issues associated with the two-component system remain, along with the potential cytotoxicity of such nanomaterials. Finally, there is the issue of material wastage by trapping it in the bulk of the polymer, away from the surface, where it cannot impact the microorganisms due to the short path length of any ROS generated within the polymeric matrix. , …”