Sound-powered microbots navigate to where they're needed in the body to slowly deliver drugs

Good news! Very clever! Very impressive! This achievement is almost spectacular! This could be a breakthrough!

"... Engineered nanoparticles make good drug carriers because they can prevent the drugs from degrading and control the rate at which they are released. However, many nanoparticles rely on blood circulation or diffusion as their primary mode of transport, which limits their ability to reach certain organs and tissues.
Researchers ... creating a tiny, self-propelled microbot that can deliver drugs quickly and effectively. ...
The microbot [diameter of only 20 micrometers], made from biocompatible polymers, was designed with a spherical cavity in its center that traps air when the bot is submerged in fluid. When the air bubble is hit with an acoustic wave, such as an ultrasound, it vibrates, propelling the tiny robot forward.  ...
To maximize non-linear movement, the bot was fitted with symmetrical and asymmetrical fins that cause it to rotate in an orbital motion and give it the appearance of a very small rocket. The fins also allow the microbot to travel at speeds of around 0.1 in (3 mm) per second ...

The researchers test-drove their tiny bubble-based, sound-powered speed demons on mice bladders. They wanted to see whether the bots could deliver medication directly to the bladder to treat interstitial cystitis ...

They fabricated thousands of microrobots with high concentrations of dexamethasone, a common steroid medication, encapsulated in their polymer matrix. When the microbots were introduced, the researchers found that they latched onto the bladder wall and released more than 90% of the dexamethasone over about two days. ..."

"Fantastic Voyage

... He imagines that, just like in the movie, microrobots could swirl through a person’s blood stream, seeking out targeted areas to treat for various ailments. ..."

From the abstract:

"Remotely powered microrobots are proposed as next-generation vehicles for drug delivery. However, most microrobots swim with linear trajectories and lack the capacity to robustly adhere to soft tissues. This limits their ability to navigate complex biological environments and sustainably release drugs at target sites. In this work, bubble-based microrobots with complex geometries are shown to efficiently swim with non-linear trajectories in a mouse bladder, robustly pin to the epithelium, and slowly release therapeutic drugs. The asymmetric fins on the exterior bodies of the microrobots induce a rapid rotational component to their swimming motions of up to ≈150 body lengths per second. Due to their fast speeds and sharp fins, the microrobots can mechanically pin themselves to the bladder epithelium and endure shear stresses commensurate with urination. Dexamethasone, a small molecule drug used for inflammatory diseases, is encapsulated within the polymeric bodies of the microrobots. The sustained release of the drug is shown to temper inflammation in a manner that surpasses the performance of free drug controls. This system provides a potential strategy to use microrobots to efficiently navigate large volumes, pin at soft tissue boundaries, and release drugs over several days for a range of diseases."

Sound-powered microbots zip to where they're needed to deliver drugs (secondary news source) Researchers have taken another step forward in medical micro-robotics, designing a tiny, speedy, self-propelled bot that may one day deliver medications directly where they’re needed inside the body.

These tiny, medical robots could one day travel through your body (primary news source)

Bubble-Based Microrobots with Rapid Circular Motions for Epithelial Pinning and Drug Delivery (no public access)

Microrobot seen under a scanning electron microscope. Look at this beauty!

Microrobot burrowed into the walls of the bladder