What are Microbubbles?

Microbubbles are small, gas-filled bubbles, typically between 0.5µm and 10µm in diameter, that are widely used as contrast agents in medical imaging and as carriers for targeted drug delivery.

Credit: venars.original/Shutterstock.com

The core of the microbubble is a gas, which is surrounded by a shell that may be composed of polymers, lipids, lipopolymers, proteins, surfactants or a combination of these.

Microbubbles are usually injected intravenously, a process that researchers have shown is safe compared to the use of conventional contrast agents in techniques such as magnetic resonance imaging and radiography.

Development of microbubbles

Microbubbles were originally developed in the 1990s to enhance ultrasound scans. They resonate in an ultrasound beam, contracting and expanding as pressure changes occur in the ultrasound wave.

Microbubbles resonate particularly vigorously at the high frequencies used in ultrasound scans, meaning they reflect these strong waves significantly more effectively than body tissues do. Since they are approximately the same size as red blood cells, they exhibit similar rheology in blood vessels and are used to measure blood flow in organs and tumors.

Once researchers realised these bubbles could circulate through the body safely, they started to consider whether they could be used for drug delivery in the treatment of cancer.

Microbubbles in cancer

Currently, chemotherapy drugs are injected intravenously and circulate in the patient’s bloodstream. Although they are designed to destroy cancer cells, they also damage healthy tissue, leading to side effects such as nausea and hair loss.

Scientists started to use microbubbles for the targeted release of drugs, which would require significantly smaller doses than when chemotherapy drugs alone are used. The shell of the microbubble can also prevent the drug from damaging healthy cells. Initial tests have shown that using microbubbles in this way is significantly more beneficial to patients, who experience dramatically reduced side effects and recover much more rapidly.

The process involves a microbubble being loaded with a drug and antibodies that target cancer cells. The microbubbles are mixed with water and injected intravenously and tracked by ultrasound until they reach tumor tissue. The frequency of the ultrasound waves is then increased to agitate the bubbles, which burst and deliver the drug directly to the tumor cells.

The future for microbubbles

The potential medical applications of microbubbles extend beyond cancer therapy. Over the last decade, researchers have made significant advances in developing microbubbles as useful agents in molecular imaging and targeted gene delivery. Different types of microbubbles possess unique properties that can be leveraged and adjusted for specialized functions.

Microbubbles and cells interaction under high-speed microscopy

Further Reading

Last Updated: Jul 19, 2023

Sally Robertson

Written by

Sally Robertson

Sally first developed an interest in medical communications when she took on the role of Journal Development Editor for BioMed Central (BMC), after having graduated with a degree in biomedical science from Greenwich University.

Citations

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

  • APA

    Robertson, Sally. (2023, July 19). What are Microbubbles?. News-Medical. Retrieved on October 31, 2024 from https://www.news-medical.net/life-sciences/What-are-Microbubbles.aspx.

  • MLA

    Robertson, Sally. "What are Microbubbles?". News-Medical. 31 October 2024. <https://www.news-medical.net/life-sciences/What-are-Microbubbles.aspx>.

  • Chicago

    Robertson, Sally. "What are Microbubbles?". News-Medical. https://www.news-medical.net/life-sciences/What-are-Microbubbles.aspx. (accessed October 31, 2024).

  • Harvard

    Robertson, Sally. 2023. What are Microbubbles?. News-Medical, viewed 31 October 2024, https://www.news-medical.net/life-sciences/What-are-Microbubbles.aspx.

Comments

  1. Christopher Park Christopher Park United States says:

    Hi Sally.  Could I get the source that states that initial tests show that using microbubbles dramatically reduced side effects and helped patients recover much more rapidly? Thanks.

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
Post

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.