Magnetoelectric Polymer-Based Nanocomposites with Magnetically Controlled Antimicrobial Activity

Abstract

The emergence of antimicrobial resistance is considered a public health problem due to the overuse and misuse of antibiotics which are losing efficacy toward an increasing number of microorganisms. Advanced antimicrobial strategies via development of alternative drugs and materials able to control microbial infections, especially in clinical settings, are urgently needed. In this work, nanocomposite films were developed from the piezoelectric polyvinylidene fluoride (PVDF) polymer, filled with nickel nanowires (NiNws) in an attempt to control and enhance the antimicrobial activity of the materials via applying a magnetic stimulus. The material was achieved through crystallization of PVDF in the electroactive βphase upon incorporation of anisotropic and negatively charged NiNws in the polymeric matrix at a concentration of 1.5 wt %. The nanocomposites have shown to possess certain antimicrobial properties, which could be considerably boosted through the application of a magnetic field. In fact, more than 55% of bacterial growth inhibition was obtained by employing controlled dynamic magnetic conditions for representative Gram-positive and Gram-negative bacteria, compared to only 25% inhibition obtained under static conditions, i.e., without magnetic stimuli application, with the antibiofilm activity clearly improved as well upon dynamic conditions. This work demonstrates a proof-of-concept for materials able to boost on demand their antimicrobial activity and opens the room for applications in novel medical devices with improved control of healthcare-associated infections.

Magnetic Nanoparticles for Biomedical Applications: From the Soul of the Earth to the Deep History of Ourselves

“…The emergency of antimicrobial resistance has led to the search for new strategies to control microbial infections. In this sense, a study about a nanocomposite film based on piezoelectric PVDF and magnetostrictive nickel nanowires (NiNws) was reported . The results showed that more than 55% of bacterial growth inhibition was obtained when submitted to a magnetic stimulus for 18 h (varying from 0 to 230 Oe with a frequency of 0.3 Hz that induce local ME voltages up to 0.115 mV).…”

Magnetoelectric Polymer Membrane-Based Electrical Microenvironment with Magnetically Controlled Antibacterial Activity

“…PVDF tailors the bacterial behavior (inhibition or proliferation) by generating different electrical environments under different mechanical stimuli (vibration frequencies of 4–40 Hz, respectively) . Magnetoelectric composites have also been shown to be able to boost antimicrobial properties by employing both mechanical and magnetic conditions . A controllable electrical environment, however, is fabricated on a piezoelectric polymer through the use of mechanical stimulation, which may limit the applications for food processing devices.…”

“…12 Magnetoelectric composites have also been shown to be able to boost antimicrobial properties by employing both mechanical and magnetic conditions. 13 A controllable electrical environment, however, is fabricated on a piezoelectric polymer through the use of mechanical stimulation, which may limit the applications for food processing devices. When a magnetoelectric material is polarized, an electrical environment adjustable via a remote magnetic field without the application of mechanical stimuli can be formed.…”

Flexible TiCux Thin Films with Dual Antimicrobial and Piezoresistive Characteristics

“…More recently, the application of physical stimuli as a means for generating antimicrobial strategies has been investigated. 19 Piezoelectric-based materials that upon the application of mechanical 20 or magnetic cues 21 induce antimicrobial effects through electroactive microenvironments have been proven as a new strategy to impart antimicrobial effects in microbiology. Such microenvironments can also be achieved/boosted by light activation upon the addition of Au or Ag nanoparticles (NPs) into the composites, mainly via reactive oxidative species (ROS) accumulation.…”