Successful manufacture of micro-cannons can fire drugs into diseased tissue

Health professionals have long dreamed of an ideal drug delivery system wherever treatment is needed in the patient's body. And now, nanoscience scientists at the University of San Diego (UCSD) have successfully tested the method of using a tiny cannon to shoot drugs at intended targets.

In the early 20th century, a German doctor named Paul Ehrlich proposed the idea of ​​converting the right amount of medicine to a specific goal instead of waiting for the drug to be transported through the bloodstream as it is now. Thus the drug is transferred in large quantities, to the right place quickly and causes less unpleasant side effects. Ehrlich called this method "magic bullet" .

Recently, Joseph Wang and Sadik Esener, two nano engineers at UCSD relied on the idea of ​​Ehlrich's "magic bullet" to create a micro cannon that used ultrasound to fire the bullets containing drugs. treatment deep into diseased tissue . Their project has just been described in ACS Nano magazine.

For a long time, in addition to applications in ultrasound, endoscopy, ultrasound is also used by researchers to treat various diseases. For example, high-frequency ultrasound may detonate stubborn plaque on the teeth and hold blood especially small blood vessels in important internal organs. Now, it is also used to deliver medicine to the right place for treatment.

Ultrasound is very useful because it does not harm humans but can focus on specific goals such as a malignant tumor. In addition to firing the pack in the right place, this method also helps the drug penetrate deeper into the tissue because the ultrasound makes the cell membrane more porous.

First, Wang and Esener created microscopic guns with a size of 5 micrometers, equivalent to the thickness of spider silk fibers . They do that by punching a hole in the cell membrane then coating it with gold and graphene oxide.

They then loaded the cannon with a micro-sized 1-micrometer (equivalent to the size of the HIV virus) made of silica and wrapped with a liquid gel solution.Perfluorocarbon (PFC) contained in gel solution will act as fuel to operate cannon. PFCs will evaporate when affected by ultrasound and create small air bubbles. These air bubbles increase in size quickly and force the micro bullet out of the barrel. This special cannon cannot be fired without PFC.

During the experiment, scientists at UCSD successfully released micro-suppository bullets into an artificial tissue. As expected of them, drug bullets can penetrate deeper into tissues.

Wang and Esener will continue to develop their special cannons to be able to "shoot" more drugs and even shoot multiple drugs at once. This method also applies to vaccination to help vaccines become more effective and safe than ever.