Antimicrobial Properties of Nanoparticles

NewsGuard 100/100 Score

Nanoparticles are potential broad-spectrum antibiotic agents, and they can overcome evolved resistances to conventional antibiotics. The over-use of regular antibiotics has created ‘superbugs’, bacteria that are resistant to almost all types of antibiotics. Nanoparticles may present a promising solution to this public health hazard.

Silver nanoparticles HRTEM. Image Credit: Daniel Ramirez-Gonzalez / Shutterstock
Silver nanoparticles HRTEM. Image Credit: Daniel Ramirez-Gonzalez / Shutterstock

Physical Characteristics of Nanoparticles

They have a large surface area to volume ratio, providing a large area which can interact with surrounding microorganisms. They may be synthesized from a variety of materials, such as polymers, lipids, or metals, and can be functionalized with a diverse number of molecules to provide targeting, stealth, or payload delivery properties to the nanoparticle. Nanoparticles have a size range of 1–100 nm.

Nano-antibiotics: A rational design of functional nanoparticles to combat bacterial infection

Drug Enhancement

Increased retention time

Nanoparticles conjugated with antibiotics offer greater retention time within the body compared with free drugs alone.  Nanoparticles bearing targeting biomolecules, such as antibodies, proteins, or DNA improve the ability to penetrate cell membranes and specifically target particular tissues, cells, or organs.

Drug release

Drug-carrier nanoparticles have increased control over the release of antibiotics at the target site, since each nanoparticle can simultaneously deliver hundreds of drug molecules to a cell. The release of drugs can take place passively, when entering a more acidic environment such as the interior of a cell, or actively, by magnetic heating of the nanoparticles once in the desired location.

Improving the potency of drugs

Silver nanoparticles in particular can enhance the effects of conventional antibiotic drugs, to which bacteria may have become resistant, by altering the permeability of the cell membrane. The silver nanoparticles themselves can act as antibiotics by destroying the plasma membrane surrounding a bacterium. They also interact with DNA and other interior components of the bacterium by releasing silver ions that generate reactive oxygen species within the cell.

Biofilm Formation

Most bacteria exist within a biofilm – a diverse collection of bacteria of different species that interact with one another, the biofilm, and their immediate environment. The biofilm requires a solid substrate, and bacteria often migrate into a biofilm using their flagella, where they multiply rapidly. The large number of cells and high rate of bacterial binary fission in a biofilm supports a diverse variety of mutations which leads to development of antibiotic resistance by bacteria within a biofilm. The biofilm also protects the bacteria from harsh external conditions. Nanoparticles can hinder biofilm formation by binding to the surface of bacteria and providing strong electrostatic interaction between the two. Rod shaped particles are more effective in destroying biofilm, most likely due to the larger surface-area-to-volume ratio.

Other Applications

In addition to direct in vivo use as antimicrobial agents, nanoparticles are being considered as antibacterial agents to be incorporated into implantable devices, such as in dentistry or heart valves, wound dressings, and bone cement.


Further Reading

Last Updated: Oct 18, 2018

Michael Greenwood

Written by

Michael Greenwood

Michael graduated from the University of Salford with a Ph.D. in Biochemistry in 2023, and has keen research interests towards nanotechnology and its application to biological systems. Michael has written on a wide range of science communication and news topics within the life sciences and related fields since 2019, and engages extensively with current developments in journal publications.  


Please use one of the following formats to cite this article in your essay, paper or report:

  • APA

    Greenwood, Michael. (2018, October 18). Antimicrobial Properties of Nanoparticles. News-Medical. Retrieved on May 21, 2024 from

  • MLA

    Greenwood, Michael. "Antimicrobial Properties of Nanoparticles". News-Medical. 21 May 2024. <>.

  • Chicago

    Greenwood, Michael. "Antimicrobial Properties of Nanoparticles". News-Medical. (accessed May 21, 2024).

  • Harvard

    Greenwood, Michael. 2018. Antimicrobial Properties of Nanoparticles. News-Medical, viewed 21 May 2024,


The opinions expressed here are the views of the writer and do not necessarily reflect the views and opinions of News Medical.
Post a new comment

While we only use edited and approved content for Azthena answers, it may on occasions provide incorrect responses. Please confirm any data provided with the related suppliers or authors. We do not provide medical advice, if you search for medical information you must always consult a medical professional before acting on any information provided.

Your questions, but not your email details will be shared with OpenAI and retained for 30 days in accordance with their privacy principles.

Please do not ask questions that use sensitive or confidential information.

Read the full Terms & Conditions.

You might also like...
Innovative nanoparticle therapy enhances recovery in severe burn patients