Fabrication and characterization of pore-selective silver-functionalized honeycomb-patterned porous film and its application for antibacterial activity

• Published in: Polymer (Guilford) Vol. 244; p. 124646
• Main Authors: Falak, Shahkar, Shin, Bo Kyoung, Yabu, Hiroshi, Huh, Do Sung
• Format: Journal Article
• Language: English
• Published: Kidlington Elsevier Ltd 23.03.2022; Elsevier BV
• Subjects: Ag-functionalization; Antibacterial; Antibacterial activity; Breath figure; Chemical reactions; Contact angle; Dilution; E coli; Electrostatic properties; Fabrication; Fluorescence; Heavy metals; Honeycomb structure; Humidity; Inorganic materials; Interfacial reaction; Materials selection; Polymers; Polystyrene; Polystyrene resins; Reducing agents; Scanning electron microscopy; Silver; Silver nitrate; Trapping; Water drops; Ag-functionalization; Breath figure; Interfacial reaction; Antibacterial; Honeycomb structure
• ISSN: 0032-3861; 1873-2291
• DOI: 10.1016/j.polymer.2022.124646

Pore-selective silver (Ag)-functionalized honeycomb-patterned (HCP) polystyrene (PS) films were fabricated via a modified breath figure method using an interfacial chemical reaction and its application for an antibacterial film using the role of micro-trapping pit was systematically studied. PS polymer solution containing ferrocene which acts as a reducing agent was cast under humid conditions containing silver nitrate (AgNO3) to induce an interfacial chemical reaction between ferrocene and AgNO3 at the water droplet/polymer solution interface. The confinement of Ag+ to the humidity is possible due to the formation of the water complex of Ag+ such as Ag+(H2O)n stabilized by the Lennard–Jones potential and electrostatic interactions. Ag+ may be carried to the polymer solution surface via the water humidity despite being a heavy metal. Scanning electron microscopy and elemental mapping analysis revealed that the pores of the obtained films were selectively coated by Ag. The contact angle of the HCP porous films was greatly decreased by the pore selective Ag functionalization, which acts as a micro-trapping pit for the antibacterial activity. The antibacterial activity of the film against Escherichia coli and Staphylococcus aureus was assessed by the micro-dilution method, selective fluorescence imaging, and crystal violet assay. The study of BF for a functional HCP film by accompanying an interfacial chemical reaction for the pore-selective Ag functionalization shows that specific metal or inorganic materials could be pore-selectively functionalized by a similar method under several conditions, thus potentially giving the HCP films various applications. [Display omitted] •Single-step fabrication of pore-selective Ag functionalized porous HCP films.•Fabrication via a modified BF technique coupled with interfacial chemical reduction.•The pore-selective reduction of AgNO3 by ferrocene present in the polymer solution.•The Ag embedded inside the pores of the HCP film served as antibacterial micro-trapping pits.