Using nanobubbles to strengthen our hearts

“As a child, I used to dream of being a doctor with a magical injection that would eliminate disease and save my patients. Years later, at the IITB-Monash Research Academy, I got an opportunity to work on a rapidly spreading medical threat—atherosclerosis—one of the leading causes of cardiovascular complications,” grins Sourabh Mehta, who is working on a research project titled, ‘Smart nanoparticles for detection of vulnerable atherosclerotic plaques and their therapeutic stabilization’.

Figure 1 Schematics of atherosclerotic plaque

Cardiovascular diseases claim approximately 30% of the world’s population every year. Atherosclerosis is a condition where low-density lipoproteins (Bad cholesterol), and other cellular components get deposited into the arterial wall and form a plaque. “This is like a time bomb developing in your artery wall,” says Sourabh. “After a while, the plaque becomes vulnerable and breaks, releasing clumps of cholesterol and cellular debris in the artery. This could eventually lead to a heart attack, which is why such plaque needs to be identified and stabilized urgently.”

Currently, there is no definite diagnosis to determine the stage of vulnerable atherosclerotic plaque. “This is what motivated me to take up a project that would develop a vulnerable-plaque-specific contrast agent for sonography. Additionally, I would like to develop a drug delivery vehicle that is industry-friendly, cost-effective, and will therapeutically stabilize the plaque,” says Sourabh.

Figure 2 in vitro characterized multimodal nanobubbles; A. Synthesized nanobubbles, B. Cryo-TEM image of nanobubbles; C. in vitro ultrasound image of nanobubbles, D. Schematic of portable ultrasound machine with ultrasound probe and display monitor, E. Schematic action of nanobubbles performing imaging and ultrasound triggered drug delivery.

“We have developed and characterized smart nanoparticles that act as ultrasound contrast agents. We refer to these nanoparticles as nanobubbles, as they contain gas in the core, just like bubbles. Using this platform, we are working on synthesis and characterization of next generation ultrasound-based multimodal contrast agents. These nanobubbles are functionalization-ready, and can thus be used for targeted multimodal contrast agents as well as image-guided drug delivery purposes at the desired diseased area to minimize side effects.”

Sourabh plans to perform pre-clinical studies of vulnerable plaque-targeted nanobubbles on atherosclerotic mice models soon. “If we succeed, this research will hopefully bridge the gap in vulnerable plaque diagnosis, and possibly set the platform for molecular-sonography-based multimodal diagnosis and therapeutic molecular delivery for treatment of other diseases like cancer and arthritis,” he adds.

The IITB-Monash Research Academy is a collaboration between India and Australia that endeavours to strengthen scientific relationships between the two countries. Graduate research scholars like Sourabh study for a dually-badged PhD from both IIT Bombay and Monash University, spending time at both institutions to enrich their research experience. Sourabh is supported by Department of Biotechnology (DBT), India.

Says Prof Murali Sastry, CEO of the Academy, “Commercialization of multimodal imaging agents or therapeutic microbubbles is the next big step in the field of diagnostic imaging. We hope that Sourabh will one day be able to realise his childhood dream and present cardiologists the option of using a multifunctional nanobubble injection to strengthen our hearts.”