During this experimental exploration of acoustic mobility phenomena, I had the chance to work wit... more During this experimental exploration of acoustic mobility phenomena, I had the chance to work with wonderful scientists, in France but also across different countries, who have enriched me with their skills and insight in quite various domains. Prof. Thomas E. Mallouk has been extremely helpful in providing us with the metallic nanoparticles used along this PhD. In addition to his knowledge in chemistry fabrication processes, he has been an exquisite guest when I did come to Penn State University to work with his team, and an very helpful collaborator to talk with on scientific but also on everyday life topics. Next I will thank Prof. John Sader and all of his University of Melbourne team, for hosting me during a month and to be so engaging in building a collaboration on the nanorods propulsion. Dr. Jesse Collis and him have been more than pedagogic in providing me with insights about their models, and in building the right set of experiment to try to prove it right. My gratitude also goes to Prof. Philippe Marmottant and Dr. Jean-Louis Thomas for accompanying me along the project in my PhD committee. For those who have never set foot in the PMMH, they may not know what it is to be cocooned in a place filled to the brim with not only bright minds, but also genuinely creative personalities, able to build amazing experiments from pieces of cardboard as well as from extremely expensive microscopes. I would like to thank here all of the lab that contributed to this PhD, and especially Justine Laurent, for having helped so much with the design and production of these tiny shape controlled objects, and for having proofread almost all of the manuscript. Xavier Benoit-Gonin, without whom none of the microgravity experiments campaigns would have take place, also holds a special position in these acknowledgements. My gratitude also goes to all of my officemates, Yacine and the everlasting debates around a coffee cup, Piotr and his perpetual enthusiasm, Joachim and his unmoveable optimism. Such a lab is a shrine to conduct research in, and I am very happy to have been able to join and build a long lasting relationship with a lot of the people in there. I would thus like to thank Nathan for all the work he shed into the PDMS channels design exploited in the following pages, Ludovic for his help performing the acoustic energy measurements presented here, Angelica for her collaboration on the optoacoustic effect investigations, and finally Jean-Luc and Mauricio for allowing this PhD to take place. Funding, collaborators and a brilliant work environment allow to conduct great research. But it is the contribution of others that I would like to emphasize now, because they enabled the would-be doctor to achieve this goal. There are few things achievable alone, playing rugby not being one of them. I do not know much sports that reward as much as this one, and especially thanks to the team spirit it creates. For almost a decade now I have been sweating and spilling my blood with you, and I would like to give you many of my thanks for your undefeatable support in a lot of situations I have crossed along this PhD project. Having a close circle of friends from childhood is a rare thing that I can appreciate to ii its exact value; friends worth that much are quite uncommon. Whether it is through the reliability of Valentin, the english skills of David, the Florians the good plans, peachy Eliott and impeaching Sandy, they have also shaped the person I am today. Several things are notorious about the ESPCI Paris. It is obviously the best school in the world, but few know that it can be the place to meet some of the finest people in life. Where would I be without them? Probably somewhere between a false train luggage and a scooter. So thank you Hubert, for sharing so many good moments for eight years now, and to have allowed all of this to take place. Thanks to the Simons, each one incarnating prime values to me, finely knowledgeable and terribly practical, cultivated and rough, thin and thick made flesh. And how to evoke something weighty without thinking of something light? Thank you Dounia, for being able to lift my spirits each time we shared together, for being incredibly positive no matter the situation. I also sincerely believe I would not be the same person as I am today without Ambre, whom I truly thank by these words. I feel quite proud to be friend with a world class handball player in the person of Thomas Guyon, with a cook as gifted as Léo and with a phenomenal piper like Flavio. But true friends can also be found at the bottom of a mine, so thank you Guillaume and Wahbi, have lit my lantern. Likewise, I had the chance to share many road memories with Hugues, Cas and Conner, my steadfast travel companions. Speaking of this learning environment cannot be done without thinking of a family that was built there, perpetuated so far with close to no snag, the one to bring them all and in power bind them. This goes to these people, each one unique and special in their personalities and behaviours, but linked by this love we have for each other, that constitutes this unity we are so proud of. Particulars thoughts are going to Theo, whose light we try to keep shining on all our events. Fortifying the tree of my achievements now, my family would be at its deepest roots. It is quite a chance to grow up surrounded by characters so enriching. Everybody thanks their loved ones. I would like to thank my family for being different, for standing against the global tendencies of society, for moulding me as I am today through the interactions we had along all these years, together. A certain gipsyness may or may not come from this crucible, however it is an asset in a constant motion world to be able to effortlessly adapt to every situation. These acknowledgements finally go to all those who could not be cited in these lines, but that will know reading it that they matter the most to me, and without which I could not take this project to its end.
Opto-acoustophoretic mobility has been demonstrated recently for fluorescent and colored particle... more Opto-acoustophoretic mobility has been demonstrated recently for fluorescent and colored particles acoustically levitated in a stationary ultrasonic field when illuminated with the appropriate optical wavelength [Dumy, Hoyos, and Aider, J. Acoust. Soc. Am. 146, 4557–4568 (2019); Zhou, Gao, Yang, Li, Shao, Zhang, Li, and Li, Adv. Sci. 5, 1800122 (2018)]. It is a repeatable phenomenon, needing both acoustic trapping and specific optic excitation to occur. However, the physical origin of the phenomenon is still debated. In this study, we provide more insights into the probable origin of this phenomenon by confronting numerical simulations with temperature controlled experiments. The phenomenon properties are well reproduced by our model, relying on a thermofluidic instability, hinting at the potential thermally induced fluid density gradient as a drag source for the observed ejection of particles. Thermostated experiments exhibit a surprising threshold above which the phenomenon is not...
HAL (Le Centre pour la Communication Scientifique Directe), Dec 10, 2018
Acoustic Radiation Force (ARF) is commonly used to create stable large-scale aggregates of partic... more Acoustic Radiation Force (ARF) is commonly used to create stable large-scale aggregates of particles in levitation (so-called "acoustic levitation) in a micro cavity. We show in the following work that this well-known and well-controlled aggregation process can be reversed without contact or external flow if the aggregated particles are enlightened with the proper optical wavelength. This coupled optics and acoustics effect has been observed with various kinds of particles and different optic wavelengths, showing high reproducibility. The phenomenon is studied using fluorescent micro-metric polystyrene particles without flow, and the effects of acoustic energy and illumination power have been quantitatively assessed. Since it is a tag free phenomenon, does not need high energies to happen and that it works with biological objects such as algae, red blood cells and bacteria, it may pave the way to a broad range of applications.
Investigation on a novel photoacoustofluidic effect
The Journal of the Acoustical Society of America, 2017
Acoustic manipulation of micro-objects (particles, cells, and bacteria) can be achieved using ult... more Acoustic manipulation of micro-objects (particles, cells, and bacteria) can be achieved using ultrasonic standing waves in a fluidic or microfluidic resonator. By matching resonator dimensions and acoustic field frequency, it is possible to use acoustic radiation force (ARF) to gather the particles in the pressure nodal (or anti-nodal) plane, creating one or several aggregates. In standard operating conditions, they can be maintained as long as needed in acoustic levitation at this equilibrium position. In this study, we present a new unexpected phenomenon. After creating a large aggregate of light-absorbing particles, we show that it is possible to force the complete breakup of the aggregate when we enlighten it with an electromagnetic wave of adequate wavelength and intensity. If the particles remain in acoustic levitation, they are quickly rejected and propelled away from the aggregate leading to its fast destruction. We show that this phenomenon strongly depends on both the ampl...
La thérapie sonodynamique (SDT) est une modalité thérapeutique découverte dans les années 1990 ma... more La thérapie sonodynamique (SDT) est une modalité thérapeutique découverte dans les années 1990 mais n'ayant pas encore d'applications cliniques approuvées. Cette technique utilise des ultrasons basse fréquence ciblés qui activent des sonosensibilisateurs conduisant à l'apoptose et la mort cellulaire. La SDT permet de traiter des tissus à des profondeurs importantes (4 à 10 cm). Cet article présente les principes physiques de la SDT, les mécanismes responsables de ses effets biologiques, les différents types de sonosensibilisateurs et les applications médicales envisagées.
the modification of the equilibrium between the axial and transverse components of the ARF. While... more the modification of the equilibrium between the axial and transverse components of the ARF. While these experiments show that some phenomena, like the propulsion of nanorods by ARF, may not be applicable in microgravity, they do confirm that acoustic manipulation of particles or cells in microgravity is possible, which paves for the development of many useful techniques for particles or cells manipulation, like cell cultures, during long-term space travel.
The Journal of the Acoustical Society of America, 2019
Acoustic Radiation Force is commonly used to create stable large-scale aggregates of particles in... more Acoustic Radiation Force is commonly used to create stable large-scale aggregates of particles in levitation (so-called “acoustic levitation”) in a micro-cavity. The authors show in the following work that this well-known and well-controlled aggregation process can be reversed without contact or external flow if the aggregated particles are enlightened with the proper optical wavelength. This coupled optics and acoustics effect has been observed with various kinds of particles and different optic wavelengths, showing high reproducibility. The phenomenon is studied using fluorescent micro-metric polystyrene particles without flow, and the effects of acoustic energy and illumination power have been quantitatively assessed. It is then exploited to separate a mix of particles with identical mechanical properties based on their different optic absorption. If the phenomenon is not well understood, some possible mechanisms are proposed and discussed that could be responsible for the rapid ...
During this experimental exploration of acoustic mobility phenomena, I had the chance to work wit... more During this experimental exploration of acoustic mobility phenomena, I had the chance to work with wonderful scientists, in France but also across different countries, who have enriched me with their skills and insight in quite various domains. Prof. Thomas E. Mallouk has been extremely helpful in providing us with the metallic nanoparticles used along this PhD. In addition to his knowledge in chemistry fabrication processes, he has been an exquisite guest when I did come to Penn State University to work with his team, and an very helpful collaborator to talk with on scientific but also on everyday life topics. Next I will thank Prof. John Sader and all of his University of Melbourne team, for hosting me during a month and to be so engaging in building a collaboration on the nanorods propulsion. Dr. Jesse Collis and him have been more than pedagogic in providing me with insights about their models, and in building the right set of experiment to try to prove it right. My gratitude also goes to Prof. Philippe Marmottant and Dr. Jean-Louis Thomas for accompanying me along the project in my PhD committee. For those who have never set foot in the PMMH, they may not know what it is to be cocooned in a place filled to the brim with not only bright minds, but also genuinely creative personalities, able to build amazing experiments from pieces of cardboard as well as from extremely expensive microscopes. I would like to thank here all of the lab that contributed to this PhD, and especially Justine Laurent, for having helped so much with the design and production of these tiny shape controlled objects, and for having proofread almost all of the manuscript. Xavier Benoit-Gonin, without whom none of the microgravity experiments campaigns would have take place, also holds a special position in these acknowledgements. My gratitude also goes to all of my officemates, Yacine and the everlasting debates around a coffee cup, Piotr and his perpetual enthusiasm, Joachim and his unmoveable optimism. Such a lab is a shrine to conduct research in, and I am very happy to have been able to join and build a long lasting relationship with a lot of the people in there. I would thus like to thank Nathan for all the work he shed into the PDMS channels design exploited in the following pages, Ludovic for his help performing the acoustic energy measurements presented here, Angelica for her collaboration on the optoacoustic effect investigations, and finally Jean-Luc and Mauricio for allowing this PhD to take place. Funding, collaborators and a brilliant work environment allow to conduct great research. But it is the contribution of others that I would like to emphasize now, because they enabled the would-be doctor to achieve this goal. There are few things achievable alone, playing rugby not being one of them. I do not know much sports that reward as much as this one, and especially thanks to the team spirit it creates. For almost a decade now I have been sweating and spilling my blood with you, and I would like to give you many of my thanks for your undefeatable support in a lot of situations I have crossed along this PhD project. Having a close circle of friends from childhood is a rare thing that I can appreciate to ii its exact value; friends worth that much are quite uncommon. Whether it is through the reliability of Valentin, the english skills of David, the Florians the good plans, peachy Eliott and impeaching Sandy, they have also shaped the person I am today. Several things are notorious about the ESPCI Paris. It is obviously the best school in the world, but few know that it can be the place to meet some of the finest people in life. Where would I be without them? Probably somewhere between a false train luggage and a scooter. So thank you Hubert, for sharing so many good moments for eight years now, and to have allowed all of this to take place. Thanks to the Simons, each one incarnating prime values to me, finely knowledgeable and terribly practical, cultivated and rough, thin and thick made flesh. And how to evoke something weighty without thinking of something light? Thank you Dounia, for being able to lift my spirits each time we shared together, for being incredibly positive no matter the situation. I also sincerely believe I would not be the same person as I am today without Ambre, whom I truly thank by these words. I feel quite proud to be friend with a world class handball player in the person of Thomas Guyon, with a cook as gifted as Léo and with a phenomenal piper like Flavio. But true friends can also be found at the bottom of a mine, so thank you Guillaume and Wahbi, have lit my lantern. Likewise, I had the chance to share many road memories with Hugues, Cas and Conner, my steadfast travel companions. Speaking of this learning environment cannot be done without thinking of a family that was built there, perpetuated so far with close to no snag, the one to bring them all and in power bind them. This goes to these people, each one unique and special in their personalities and behaviours, but linked by this love we have for each other, that constitutes this unity we are so proud of. Particulars thoughts are going to Theo, whose light we try to keep shining on all our events. Fortifying the tree of my achievements now, my family would be at its deepest roots. It is quite a chance to grow up surrounded by characters so enriching. Everybody thanks their loved ones. I would like to thank my family for being different, for standing against the global tendencies of society, for moulding me as I am today through the interactions we had along all these years, together. A certain gipsyness may or may not come from this crucible, however it is an asset in a constant motion world to be able to effortlessly adapt to every situation. These acknowledgements finally go to all those who could not be cited in these lines, but that will know reading it that they matter the most to me, and without which I could not take this project to its end.
Opto-acoustophoretic mobility has been demonstrated recently for fluorescent and colored particle... more Opto-acoustophoretic mobility has been demonstrated recently for fluorescent and colored particles acoustically levitated in a stationary ultrasonic field when illuminated with the appropriate optical wavelength [Dumy, Hoyos, and Aider, J. Acoust. Soc. Am. 146, 4557–4568 (2019); Zhou, Gao, Yang, Li, Shao, Zhang, Li, and Li, Adv. Sci. 5, 1800122 (2018)]. It is a repeatable phenomenon, needing both acoustic trapping and specific optic excitation to occur. However, the physical origin of the phenomenon is still debated. In this study, we provide more insights into the probable origin of this phenomenon by confronting numerical simulations with temperature controlled experiments. The phenomenon properties are well reproduced by our model, relying on a thermofluidic instability, hinting at the potential thermally induced fluid density gradient as a drag source for the observed ejection of particles. Thermostated experiments exhibit a surprising threshold above which the phenomenon is not...
HAL (Le Centre pour la Communication Scientifique Directe), Dec 10, 2018
Acoustic Radiation Force (ARF) is commonly used to create stable large-scale aggregates of partic... more Acoustic Radiation Force (ARF) is commonly used to create stable large-scale aggregates of particles in levitation (so-called "acoustic levitation) in a micro cavity. We show in the following work that this well-known and well-controlled aggregation process can be reversed without contact or external flow if the aggregated particles are enlightened with the proper optical wavelength. This coupled optics and acoustics effect has been observed with various kinds of particles and different optic wavelengths, showing high reproducibility. The phenomenon is studied using fluorescent micro-metric polystyrene particles without flow, and the effects of acoustic energy and illumination power have been quantitatively assessed. Since it is a tag free phenomenon, does not need high energies to happen and that it works with biological objects such as algae, red blood cells and bacteria, it may pave the way to a broad range of applications.
Investigation on a novel photoacoustofluidic effect
The Journal of the Acoustical Society of America, 2017
Acoustic manipulation of micro-objects (particles, cells, and bacteria) can be achieved using ult... more Acoustic manipulation of micro-objects (particles, cells, and bacteria) can be achieved using ultrasonic standing waves in a fluidic or microfluidic resonator. By matching resonator dimensions and acoustic field frequency, it is possible to use acoustic radiation force (ARF) to gather the particles in the pressure nodal (or anti-nodal) plane, creating one or several aggregates. In standard operating conditions, they can be maintained as long as needed in acoustic levitation at this equilibrium position. In this study, we present a new unexpected phenomenon. After creating a large aggregate of light-absorbing particles, we show that it is possible to force the complete breakup of the aggregate when we enlighten it with an electromagnetic wave of adequate wavelength and intensity. If the particles remain in acoustic levitation, they are quickly rejected and propelled away from the aggregate leading to its fast destruction. We show that this phenomenon strongly depends on both the ampl...
La thérapie sonodynamique (SDT) est une modalité thérapeutique découverte dans les années 1990 ma... more La thérapie sonodynamique (SDT) est une modalité thérapeutique découverte dans les années 1990 mais n'ayant pas encore d'applications cliniques approuvées. Cette technique utilise des ultrasons basse fréquence ciblés qui activent des sonosensibilisateurs conduisant à l'apoptose et la mort cellulaire. La SDT permet de traiter des tissus à des profondeurs importantes (4 à 10 cm). Cet article présente les principes physiques de la SDT, les mécanismes responsables de ses effets biologiques, les différents types de sonosensibilisateurs et les applications médicales envisagées.
the modification of the equilibrium between the axial and transverse components of the ARF. While... more the modification of the equilibrium between the axial and transverse components of the ARF. While these experiments show that some phenomena, like the propulsion of nanorods by ARF, may not be applicable in microgravity, they do confirm that acoustic manipulation of particles or cells in microgravity is possible, which paves for the development of many useful techniques for particles or cells manipulation, like cell cultures, during long-term space travel.
The Journal of the Acoustical Society of America, 2019
Acoustic Radiation Force is commonly used to create stable large-scale aggregates of particles in... more Acoustic Radiation Force is commonly used to create stable large-scale aggregates of particles in levitation (so-called “acoustic levitation”) in a micro-cavity. The authors show in the following work that this well-known and well-controlled aggregation process can be reversed without contact or external flow if the aggregated particles are enlightened with the proper optical wavelength. This coupled optics and acoustics effect has been observed with various kinds of particles and different optic wavelengths, showing high reproducibility. The phenomenon is studied using fluorescent micro-metric polystyrene particles without flow, and the effects of acoustic energy and illumination power have been quantitatively assessed. It is then exploited to separate a mix of particles with identical mechanical properties based on their different optic absorption. If the phenomenon is not well understood, some possible mechanisms are proposed and discussed that could be responsible for the rapid ...
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