3D Hierarchical Polyaniline–Metal Hybrid Nanopillars: Morphological Control and Its Antibacterial Application

Abstract

Effective and reliable antibacterial surfaces are in high demand in modern society. Although recent works have shown excellent antibacterial performance by combining unique hierarchical nanotopological structures with functional polymer coating, determining the antibacterial performance arising from morphological changes is necessary. In this work, three-dimensional (3D) hierarchical polyaniline–gold (PANI/Au) hybrid nanopillars were successfully fabricated via chemical polymerization (i.e., dilute method). The morphology and structures of the PANI/Au nanopillars were controlled by the reaction time (10 min to 60 h) and the molar concentrations of the monomer (0.01, 0.1, and 1 M aniline), oxidant (0.002, 0.0067, 0.01, and 0.02 M ammonium persulfate), and acid (0.01, 0.1, 1, and 2 M perchloric acid). These complex combinations allow controlling the hierarchical micro- to nanostructure of PANI on a nanopillar array (NPA). Furthermore, the surface of the 3D PANI/Au hierarchical nanostructure can be chemically treated while maintaining the structure using initiated chemical vapor deposition. Moreover, the excellent antibacterial performance of the 3D PANI/Au hierarchical nanostructure (HNS) exceeds 99% after functional polymer coating. The excellent antibacterial performance of the obtained 3D PANI/Au HNS is mainly because of the complex topological and physicochemical surface modification. Thus, these 3D PANI/Au hierarchical nanostructures are promising high-performance antibacterial materials.

Laser Direct Writing of Dual-Scale 3D Structures for Cell Repelling at High Cellular Density

“…We particularly aim to optimize the structures’ design and the laser writing parameters (laser power, scan speed) for improving the cell-repellent properties of the structures at high cellular densities in the culture medium (i.e., cellular densities in the culture medium up to five times higher than we previously used). The present study opens up new perspectives regarding the potential of the cell-repellent structures, such as for the development of biosensors that require poor or no cell adherence to the sensor surface [ 40 ], of implantable chips where adherent proteins and cells might cause the inflammation of the implantation site [ 41 , 42 , 43 ], as well as for the development of antibacterial surfaces [ 44 , 45 ].…”