Micro-autonomous systems

Chemotherapeutic micromotor for targeted drug delivery

Chemotherapeutic micromotor for targeted drug delivery

A sperm-driven micromotor acts as a targeted drug delivery system to potentially treat diseases in the female reproductive tract. More precisely, the sperm cell of the micromotor system is first loaded with an anticancer drug (DOX-HC). Then the system is guided by a synthetic magnetic harness to an in-vitro cultured tumor spheroid. Finally, the drug is delivered locally into the tumour once the sperm cell is freed by an integrated mechanical release mechanism.

H. Xu et al., ACS Nano 12, 327 (2018) URL PDF

This work was highlighted in:

  • SZ-ONLINE.de (March 2018) URL
  • Spektrum.de (February 2018) URL
  • derStandard.at (January 2018) URL
  • Daily Beast (January 2018) URL
  • The New Indian Express (December 2017) URL
  • Live Science (December 2017) URL
  • ACS Chemistry for Life (December 2017) URL
  • ACS Publications (December 2017) URL
  • Mail Online (December 2017) URL
  • Big Think (December 2017) URL
  • New scientist (December 2017) URL
  • MIMS Today (May 2017) URL
  • Bild (April 2017) URL
  • Science (April 2017) URL
  • Mach (June 2017) URL
  • BioTechniques (June 2017) URL
  • Longvity (June 2017) URL
  • Scientifist (April 2017) URL
  • Phys.org (April 2017) URL
  • 3ders.org (April 2017) URL
  • 3D Printing Industry (April 2017) URL
  • Medical Daily (April 2017) URL
  • Medimagazin (April 2017) URL
  • MIT Technology Review (April 2017) URL

 

Opportunities and challenges of medical microbots

Opportunities and challenges of medical microbots

Scientists are designing microscopic devices — microbots and micromotors — to eventually move through the body to perform medical tasks. So far, most microbot experiments have been done in vitro under conditions very different from those in the human body. In our extended comment we call on microrobotics researchers, materials scientists and bioimaging and medical specialists to work together to tackle the challenges on the way to in-vivo applications. And regulatory agencies need to put in place directives for testing therapeutics that are based on microbots.

M. Medina-Sánchez, O.G. Schmidt, Nature 545, 406 (2017) URL PDF

Sperm cells as components for microbots

Sperm cells as components for microbots

Spermatozoa are promising components for microbots serving as biocompatible propulsion source, but also offering other interesting features such as their ability to fertilize, to respond to stimuli, or their ability to take up drugs which reveals fascinating new applications. Our recent article describes how spermatozoa can be useful parts of microdevices. It summarizes the recent progress on developing tubular and helical spermbots. The article provides also insight about the influencing factors on the performance of the spermbots and current challenges as well as future perspectives.

V. Magdanz et al., Adv. Mater. 29, 24 (2017) URL

This work was highlighted in:

  • Nanowerk (May 2017) URL
  • Advanced Science News (April 2017) URL
Micromotorized sperms for artificial fertilization

Micromotorized sperms for artificial fertilization 

We present artificially motorized sperm cells—a novel type of hybrid micromotor, where customized microhelices serve as motors for transporting sperm cells with motion deficiencies to help them carry out their natural function. We manage to drive the motorized sperms to an oozyte for potential fertilization and then release it. Despite the fact that there still remain some challenges on the way to achieve successful fertilization, we believe that the potential of this novel approach toward assisted reproduction can be already put into perspective with the present work. 

M. Medina-Sanchez et al., Nano Lett. 16, 555 (2016) URL PDF

This work was highlighted in:

  • Zeit Online (March 2018) URL
  • SZ-ONLINE.de (March 2018) URL
  • Spektrum.de (February 2018) URL
  • C&EN (April 2016) URL PDF
  • wsj.com (January 2016) URL
  • rmanj.com (January 2016) URL
  • ACS Chemistry for Life (January 2016) URL
  • cbsnews.com (January 2016) URL 
  • sciencemag.org (January 2016) URL 
  • spektrum.de (January 2016) URL
  • dradiowissen.de (January 2016) URL
  • dailymail.co.uk/sciencetech (January 2016) URL
  • dailymail.co.uk/health (January 2016) URL
  • bbc.com (January 2016) URL
  • bostoncommons.net (January 2016) URL
  • gizmag.com (January 2016) URL
  • Mail Online (January 2016) URL
  • Phys.org (January 2016) URL
Cancer treatment by dual-action biogenic microdaggers

Cancer treatment by dual-action biogenic microdaggers

We present dual-action biogenic microbots with a dagger-like morphology for cellular microsurgery and drug delivery. These biocompatible micromotors allow magnetically controlled drilling into a target cell along with the sustained release of a loaded drug. This study highlights “selective targeting and destruction” of harmful cells in living systems and advances the understanding of microscale interactions at the cellular level.

S. K. Srivastava et al., Adv. Mater. 28, 832 (2016) URL PDF

This work was highlighted in:

  • The Scientist (June 2016) URL
  • Science (January 2016) PDF
Efficient wastewater cleaning by self-propelled micromotors

Efficient wastewater cleaning by self-propelled micromotors

We present efficient wastewater-mediated activation of catalytic micromotors for the degradation of nitroaromatic pollutants in water. Our next-generation hybrid micromotors are fabricated by growing catalytically active Pd particles over thin-metal films, which are then rolled-up into self-propelled tubular microjets. The high catalytic efficiency obtained via a wet-lab approach has promising potential in creating hybrid micromotors comprising multicatalytic systems assembled into one entity for sustainable environmental remediation and theranostics.

S.K. Srivastava et al., Nano Lett. 16, 817 (2016) URL PDF

This work was highlighted in: 

  • ChemistryViews.org URL
Ultra-compact helical antennas for smart system implants

Ultra-compact helical antennas for smart system implants

Ultra-compact helical antennas with a total length five times smaller compared to their conventional dipole counterparts are demonstrated to operate in the Industry-Scientific-Medical radio band. The antennas can be implanted by standard medical syringes and inter-antenna as well as antenna-smartphone communication is reported. Our work highlights the potential of helical antennas for medical applications as components of smart system implants. 

D. D. Karnaushenko et al., NPG Asia Mater. 7, e188 (2015) URL PDF

This work was highlighted in:

  • Surgical Tribune (November 2015) URL
Flexible thermoresponsive microjets

Flexible thermoresponsive microjets

Flexible self-propelled microjets are formed by temperature-induced folding of thin polymer films into microtubes that contain an inner platinum layer for catalytic bubble propulsion in hydrogen peroxide. The polymer films are bilayers of an active and a passive component, which cause the microjets to fold and unfold reversibly by applying slight temperature changes. The speed control by shaping the polymeric Pt films offers a unique approach to operate this new kind of flexible bubble-propelled micromotors. This work was carried out in collaboration with the Leibniz Institute of Polymer Research Dresden, the TU Dresden and the Max-Planck-Institute for Intelligent Systems in Stuttgart.

V. Magdanz et al., Angew. Chem. Int. Ed. 53, 2673 (2014) URL PDF

A sperm driven micro-bio-robot

A sperm driven micro-bio-robot 

A new biohybrid micro-robot is developed by capturing bovine sperm cells inside ferromagnetic microtubes that use the motile cells as driving force. These micro-bio-robots can be remotely controlled by an external magnetic field. The performance of micro-robots is described in dependence on tube radius, cell penetration and temperature. The combination of a biological power source and a microdevice is a compelling approach to the development of new microrobotic devices with fascinating future applications such as in-vivo artificial fertilization. 

V. Magdanz et al., Adv. Mater. 25, 6581 (2013) URL PDF

This work was highlighted in:

  • SZ-ONLINE.de (March 2018) URL
  • www.roboticstomorrow.com (March 2015) URL
  • news.discovery.com (January 2014) URL
  • Phys.org (January 2014) URL
  • Deutschlandfunk (January 2014) URL
  • Gizmag (January 2014) URL
  • FOX News (December 2013) URL
  • Science for the Curious Discover (December 2013) URL
  • The Independent (December 2013) URL
  • New Scientist (December 2013) URL
  • Vice Media Inc. (December 2013) URL
  • Le figaro - fr (December 2013) URL
  • FierceDrugDelivery (December 2013) URL
  • Tech Times (December 2013) URL
Chemotactic behaviour of artificial engines

Chemotactic behaviour of artificial engines

When man-made self-powered micromotors swim in a gradient of chemical fuel, they experience a chemical attraction towards the fuel and deviate from their otherwise random motion. We now report that self-propelled microjets and microparticles change their trajectory when hydrogen peroxide fuel is added to the solution in which they navigate, a response similar to the chemotactic behavior of some living organisms.

L. Baraban et al., Angew. Chem. Int. Edit. 52, 5552–5556 (2013) URL PDF

Self-propelled nanotools drilling into cells

Self-propelled nanotools drilling into cells

We design nanoscale tools in the form of autonomous and remotely guided catalytically self-propelled rolled-up tubes. If these tubes are rolled-up in an asymmetric fashion they move in a corkscrew-like trajectory and rotate with high frequency around their own axis. This rotating motion allows them to drill into cell material (here: fixed HeLa cells). Since they can be remotely controlled by an external magnetic field, deliberate non-invasive nano-surgery might become reality in the far future.

A. A. Solovev et al., ACS Nano 6, 1751 (2012) URL PDF

Fabrication and applications of large arrays of multifunctional rolled-up SiO/SiO2 microtubes

Fabrication and applications of large arrays of multifunctional rolled-up SiO/SiO2 microtubes

Biocompatible, multifunctional large arrays of transparent SiO/SiO2 microtubes are fabricated by rolled-up nanotech. The outer tubular diameter as a function of thicknesses of SiO and SiO2has been systematically studied and the roll-up parameters have been optimized to deterministically achieve a yield of nearly 100%. A macroscopic continuum mechanical model is in good agreement with the experimental data. The relative ease in functionalization of the “glass” microtubes with different biomaterials renders rolled-up nanotech an excellent option for various on- and off-chip applications, including optofluidic sensors, micro-engines and pre-patterned 3D scaffolds for cell culturing.

S. M. Harazim et al., J. Mater. Chem. 22, 2878 (2012) URL PDF

"Starting" and "stopping" microjet engines

"Starting" and "stopping" microjet engines

The control over the autonomous motion of artificial nano/micromachines is essential for real biomedical and nanotechnological applications. Consequently, a complete nanomachine should be able to be turned on and off at will. We report the tuning of the propulsion power of catalytic microjets through illumination of a solution by a white-light source. We show that light suppresses the generation of microbubbles, stopping the engines if they are fixed-to or self-propelled above a platinum-patterned surface. The microjets are reactivated by dimming the light source that illuminates the fuel solution.

A. A. Solovev et al., Angew. Chem. Int. Edit. 50, 10875–10878 (2011) URL PDF

Superfast motion of catalytic microjet engines at physiological temperature

Superfast motion of catalytic microjet engines at physiological temperature

We reduced the toxicity of the fuel used to self-propel artificial nanomachines. At physiological temperatures, i.e. 37°C, only very small amounts of H2O2 as fuel is needed to propel the microjets. Under those conditions, Fibroblast cells are viable for more than 1 hour which is highly important for the not-too-distant use of artificial nanomachines in biomedical applications. In addition, at 5% H2O2, the microjets acquire superfast speeds reaching 10 mm sec-1. The dynamics of motion is altered while increasing the speed, i.e. the motion deviates from the linear to curvilinear trajectories which has been theoretically modelled.

S. Sanchez et al., J. Am. Chem. Soc. 133, 14860 (2011) URL PDF

This work was highlighted in:

New Scientist, 2832 (2011) (Oct 2, 2011) URL

Towards remotely controlled intelligent microrobots

Towards remotely controlled intelligent microrobots

In this tutorial review we describe recent progress on catalytic microtubular engines fabricated by rolled-up nanotech. The control over speed, directionality and interactions of the microengines to perform tasks such as cargo transportation is also discussed. Since rolled-up nanotech on polymers can easily integrate almost any type of inorganic material, huge potential and advanced performance such as high speed, cargo delivery, motion control, and dynamic assembly are foreseen-ultimately promising a practical way to construct versatile and intelligent catalytic tubular microrobots.

Y. F. Mei et al., Chem. Soc. Rev. 40, 2109 (2011) URL PDF

This work was highlighted in:

  • der Standard.at (March 8, 2011) URL
  • LiLipuz (March 9, 2011)
  • Blick.ch (March 9, 2011) URL
Guinness World Record® for "Smallest Man-Made Jet Engine"

Guinness World Record® for "Smallest Man-Made Jet Engine"

"The smallest man-made jet engine measures just 600nm across and weighs 1 picogram. It was produced by Alex A. Solovev, Samuel Sanchez, Yongfeng Mei and Oliver G. Schmidt at the Leibniz Institute for Solid State and Materials Research (IFW Dresden)." This is the text of the official certificate issued by Guinness World Records® beginning of this year (see left side for scanned original).

This achievement was highlighted in:

  • Pro-Physik.de (March 8, 2011) URL
  • Die Welt (March 8, 2011) URL
  • Scinexx (March 9, 2011) URL
  • Nanowerk (March 9, 2011) URL
Microbots swimming in the flowing streams of microfluidic channels

Microbots swimming in the flowing streams of microfluidic channels

The motion of artificial catalytic nanomachines is commonly studied in free bulk solution, which differs significantly from the stream-like channel networks existing in the human body. Here, we demonstrate that catalytic microbots can self-propel in the microchannels of a microfluidics system and transport multiple spherical microparticles into desired locations. We also show for the first time that artificial micromachines can easily swim against strong flowing streams.The integration of “smart and powerful” microbots with microchips will lead to plentiful functions in lab-on-a-chip devices including e.g. efficient and convenient drug or cell separation.

S. Sanchez et al., J. Am. Chem. Soc. 133, 701 (2011) URL PDF

Transport of animal cell material by catalytic microbots

Transport of animal cell material by catalytic microbots

Animal cells can be transported within a fluid in a controllable manner by using artificial microbots. The Ti/Fe/Pt rolled-up catalytic microjet engine (microbot) is guided towards a specific cell, which is moved to a desired location where it is released. The direction of the microbots is easily steered by using an external small magnetic field. This work paves the way to future biomedical applications of artificial micromachines such as curing unhealthy cells or separation of cancer cells.

S. Sanchez et al., Chem. Commun. 47, 698 (2011) URL PDF

Collective behaviour of artifcial autonomous systems

Collective behaviour of artifcial autonomous systems

Artificial autonomous systems act as catalytic water striders at the air–liquid interface of hydrogen peroxide solution. Such systems, buoyed by oxygen bubbles, self-propel at the fuel surface by the bubble recoiling mechanism and dynamically self-assemble into patterns due to the meniscus-climbing effect. Artificial systems like these are ideally suited to study the collective behaviour of a large number of individuals, where repelling engine power competes against attractive surface tension. Our results give way to many new approaches to sense environment with swarms of micro-/nanoengineered microtube robots.

A. A. Solovev et al., Adv. Mater. 22, 4340 (2010) URL PDF

This work was highlighted in:

  • Nanowerk.com (Sep 30, 2010) URL
  • MaterialsViews (Nov 10, 2010) 
Highly efficient locomotion of hybrid biocatalytic microengines

Highly efficient locomotion of hybrid biocatalytic microengines

We have designed a novel hybrid biocatalytic microengine. The engine is based on a catalytic enzyme, catalase, specifically bounded to self-assembled monolayers covering the inside wall of an inorganic rolled-up microtube. This novel approach leads to faster, more powerful, and more efficient microengines requiring much lower concentrations of peroxide fuel. The engine's speed and direction is dynamically controlled by the friction of bubbles attached to the outside wall of the microtube. Our work presents a major step towards engineering micro-/nanorobots which run on biocompatible fuels and which - one day - might well sense their environment biochemically.

S. Sanchez et al., J. Am. Chem. Soc. 132, 13144 (2010) URL PDF

This work was highlighted in:

  • RSC Chemistry World (July 29, 2010) URL
  • Nanowerk.com (Aug 3, 2010) URL
  • ChemViews Magazine (Aug 11, 2010) URL
Magnetic control of tubular catalytic microbots

Magnetic control of tubular catalytic microbots

We have demonstrated the magnetic control of self-propelled catalytic Ti/Fe/Pt rolled-up microtubes (microbots). The microbots move by ejecting microbubbles, which are produced by a platinum catalytic decomposition of hydrogen peroxide into oxygen and water. The particularly easy control over the movement of the microbots by changing the direction of the magnetic field during motion helps to accurately load and deliver cargo at desired places in a fluid. Our microbots show a high propulsion power that allows the selective transport of up to 60 polystyrene microparticles and several thin metallic nanoplates. Our microbots represent an exciting artificial species to be employed for applications such as controllable drug-delivery and cleaning tasks.

A. A. Solovev et al., Adv. Funct. Mater. 20, 2430 (2010) URL PDF

This work was highlighted in:

Nanowerk.com (Aug 3, 2010) URL

Microtubular jet engines

Microtubular jet engines

We have strain-engineered microtubes traveling as self-propelled catalytic microjet engines along various trajectories with speeds up to ≈ 2 mm s-1 (approximately 50 body lengths per second). The motion of the microjets is generated by gas bubbles thrust out of one opening of the tube. The trajectories of various geometries can be traced by long microbubble tails. A magnetic layer is integrated into the wall of the microjet engine, which allows easy control over the direction of motion by applying external magnetic fields.

A. A. Solovev et al., Small 5, 1688 (2009) URL PDF

Ferngesteuerte Mikroraketen

Ferngesteuerte Mikroraketen

Wir haben winzige Mikroraketen hergestellt, die sich durch ein Magnetfeld fernsteuern lassen. Die Herstellung der Mikroraketen erfolgt durch hauchdünne Schichtsysteme, die sich auf einem Trägersubstrat von selbst zu Mikroröhrchen aufrollen. Nach dem Ablösen der Röhrchen von dem Substrat erzeugen die chemisch aktiven Innenwände eine katalytische Reaktion in einer Flüssigkeit. Die Reaktion führt zur Bildung von Sauerstoffblasen, die aus den Röhrchen ausgestoßen werden, und so für den Vortrieb der Mikrorakete sorgen. Da das aufgerollte Schichtsystem magnetische Materialien enthält, können die Mikroraketen durch ein Magnetfeld ferngesteuert werden.

Oliver G. Schmidt, Spektrum der Wissenschaft, S.16, Juli 2009 URL
Oliver G. Schmidt, Welt der Physik 16.05.2009 URL

*click on pictures to see animation

Strain engineered micro-/nanotubes on polymers

Strain engineered micro-/nanotubes on polymers

A generic approach has been developed to engineer tubular micro-/nanostructures out of many different materials with tunable diameters and lengths by precisely releasing and rolling up functional nanomembranes on polymers. The technology spans across different scientific fields ranging from photonics to biophysics and we demonstrate optical ring resonators, magneto-fluidic sensors, remotely controlled microjets and 2D confined channels for cell growth guiding.

Y. F. Mei et al., Adv. Mater. 20, 4085 (2008) URL PDF

This work was highlighted in:

  • P.M. Magazine (February 17, 2009) URL
  • Frankfurter Allgemeine Zeitung (November 11, 2008) URL
  • Nanowerk (October 20, 2008) URL
  • Pro Physik (October 20, 2008) URL
  • Bild (August 27, 2008) URL
Professor Oliver G. Schmidt

Director:

Prof. Dr. Oliver G. Schmidt
IFW Dresden
Helmholtzstr. 20
D-01069 Dresden

Contact: 

Office
Kristina Krummer
office-iin (at) ifw-dresden.de
Phone:+49 351 4659 810
Fax:+49 351 4659 782