La délivrance ciblée de médicaments pourrait bénéficier d’une nouvelle technique impliquant des ondes sonores

Déplacer des objets sans les toucher

Modern science has discovered ways to move things without touching them. This was first done with so-called optical tweezers, which use light, and soon replicated with acoustic tweezers, which use sound.

Les pinces acoustiques sont d’un intérêt particulier car elles peuvent pénétrer la plupart des matériaux. Leur large gamme de fréquences permet de manipuler des objets de tailles diverses, des cellules individuelles aux objets complexes. Elles sont également inoffensives pour les tissus biologiques.

Pour cette raison, les pinces acoustiques pourraient avoir de nombreuses applications, de la chirurgie à la délivrance de médicaments. Le problème est que, jusqu’à présent, le contrôle précis lors de leur utilisation était difficile dans un environnement complexe comme le corps vivant.

This is changing, thanks to nouvelles découvertes publiées dans Nature Physics by researchers at the EPFL (Switzerland) and the Vienna University of Technology (Austria).

Pousser avec des ondes sonores

The research team used a new method to create acoustic tweezers called “wave-momentum shaping”. The technique is the adaption to sound waves of a novel method using light to organize it despite a “messy” environment.

Essentiellement, elle « cartographie » d’abord l’effet de diffusion des obstacles dans une structure matricielle (à droite ci‑dessous), permettant de déterminer comment utiliser les pinces malgré les obstacles sur le trajet.

Cette matrice de diffusion évolue en temps réel au fur et à mesure que l’objet se déplace, et la maintenir à jour en temps réel a été l’une des principales réalisations des chercheurs, qui ont utilisé des outils mathématiques complexes pour y parvenir.

Source: Nature

Cela change la façon dont les pinces acoustiques fonctionnent. Normalement, la méthode piège un objet à un endroit. Ici, les ondes sonores le poussent doucement le long, comme une crosse de hockey poussant un palet.

La méthode fonctionne avec des objets sphériques, mais aussi avec des formes plus complexes. Elle peut également contrôler les rotations, ajoutant plus de flexibilité aux mouvements possibles. Elle peut fonctionner avec pratiquement n’importe quel matériau, la cible n’ayant pas besoin d’être magnétique ou particulièrement résistante.

Source: Nature

Applications possibles

Médical & Biotechnologie

The possibility of direct therapeutic treatment throughout the body without surgery is pretty interesting. This could especially be used for cancer therapy, where delivery of the drug directly into the tumor could strongly boost efficiency.

“Certaines méthodes de délivrance de médicaments utilisent déjà des ondes sonores pour libérer des médicaments encapsulés, si bien que cette technique est particulièrement attrayante pour pousser un médicament directement vers les cellules tumorales”

Similarly, biological analysis and taking samples could be done without directly touching the tissues, reducing the risk of contamination or damage caused by the procedure.

Lastly, it could also be used for tissue engineering or even 3D bioprinting. Authorizing manipulation without having to cut through could help create more complex designs, bringing us one step closer to the rêve de produire des organes à la demande.

Fabrication

Moving at will in all directions, small particles sounds exactly what 3D printing is trying to achieve.

In that respect, acoustic tweezers could be a new method to add to existing additive manufacturing techniques, arranging the particles before they are bound together into a solid object.

It could also be used to assemble together separate parts, even when direct manipulation would not be possible.

Pas le premier ?

We already cover a similar technology in our article “Les émetteurs d’énergie acoustique pourraient bientôt éliminer le besoin d’incision pendant la chirurgie”.

In it, we explained how another type of optical tweezers could achieve similar results. In that case, the focus was more on performing surgery without any cuts and moving small objects inside the body.

This was, however, more of a “classical” type of optical tweezer, locking the object in one spot.

In both cases, acoustic tweezers are making strong progress in their fundamental sciences, either for surgery with a real-time view through echography or with extremely precise pushing systems and up-to-date scattering matrix to keep the intended movement accurate.

So we should now get into the step where these technologies will be standardized and commercialized, helping push new innovative types of therapies and boost the efficiency of existing ones.

Entreprises de manipulation 3D

While one of the most advanced robotic surgery systems is sold by Intuitive Surgical (ISRG )  (ISRG), the company has less expertise in ultrasound or endoscopy than some of its competitors. So, it is likely that the first real-life medical application of acoustic tweezers might come from medical device companies already adept at integrating together many medical device systems like robots or surgery tools.

Alternatively, the progress in acoustic tweezers could benefit greatly from 3D printing and bioprinting, so a leading company in this sector might benefit as well.

1. Medtronic plc

Medtronic is a medical device leader, especially in surgery and intensive care. While the other segments could also be considered as afferent to it, the medical surgical segment of Medtronic represents $2.1B of revenues, out of a total of $7.7B.

Source: Medtronic

The company has been growing through organic growth, thanks to a large percentage of the R&D budget ($2.7B in 2022) and acquisitions (9 in 2022 and $3.3 worth of further acquisitions considered for 2023).

Medtronic sees a massive opportunity for simpler, low-cost robotic surgery:

“only 2% of surgeries around the world are held with the assistance of robots. There’s 98% out there that needs to be done via robotically-assisted surgery but not today because of the cost and utilization burdens”

It is with that strategy in mind that Medtronic has developed the Hugo system.

Source: Medtronic

It also sells the Mazor X Stealth spinal robot-assisted surgery device, thanks to its $1.7 billion acquisition of Mazor Robotics in décembre 2018.

Overall, the sterling reputation of Medtronics and its presence in virtually every hospital for at least some equipment gives it a good entry point to capture a solid part of the nascent robotic surgery market, either through internal development or acquisitions.

It also already sells endoscopic ultrasound systems, and its presence in cardiology could help apply the acoustic tweezer technology to cardiovascular therapies and surgeries.

2. Cyfuse Biomedical K.K.

The Japanese company was founded in 2010 and started selling 3D printers to researchers in 2013.

Its focus is producing tissues and organs without any artificial scaffolding, only the cells themselves, through its S-Spike platform. This is an ambitious goal, but also the final form of 3D bioprinting likely to be adopted over time.

The absence of scaffolding could prove crucial to producing “premium” organs as close as possible to native organs. The technology can only 3D print 2-3cm organ pieces at a time.

Source: Cyfuse Biomedical

It targets 4 segments: articulations, liver, nerve, and blood vessels. It could also be used to create “training” organs for surgeons, helping them learn without risking a patient’s life.

Source: Cyfuse Biomedical

Cyfuse is, for now, not profitable (after a brief period of profit in 2021) but is already registering a few million dollars in revenues.

This company is for patient investors, counting on this technology to become more mainstream and improve to the point where it can build full organs at once in one block.

In that respect, advanced acoustic tweezers might be missing steps to assemble more complex and large organs.