Controllable continuous release of functional materials from capsules is one of the unmet functions of theragnosis particles; on this way, understanding cargo-fluid interactions in vitro is an essential milestone. We develop a flexible platform to investigate single particle-fluid interactions utilizing a glass micropipette as a highly localized flow source around an optically trapped particle. In proof-of-concept experiments, this microparticle is sensitive to local microflow distribution, thus serving as a probe.
View Article and Find Full Text PDFLaser beams, capable of controlling the mechanical motion of micron-scale objects, can serve as a tool, enabling investigations of numerous interaction scenarios under full control. Beyond pure electromagnetic interactions, giving rise to conventional gradient forces and radiation pressure, environment-induced thermal effects can play a role and, in certain cases, govern the dynamics. Here we explore a thermocapillary Marangoni effect, which is responsible for creating long-range few hundreds of nano-Newton forces, acting on a bubble around a 'gilded vaterite' nanoparticle.
View Article and Find Full Text PDFWe propose a novel versatile colloidal crystal transfer technique compatible with a wide range of water-insoluble substrates regardless of their size, material, and wettability. There are no inherent limitations on colloidal particles material and size. The method possibilities are demonstrated via the colloidal transfer on quartz, glass substrates with a flat and curved surface, and via the fabrication of 3D colloidal structure with 5 overlaid colloidal monolayers.
View Article and Find Full Text PDFThe work considers the effect of extraordinary optical transmission (EOT) in polycrystalline arrays of nanopores fabricated via nanosphere photolithography (NPL). The use of samples with different qualities of polycrystalline structure allows us to reveal the role of disorder for EOT. We propose a phenomenological model which takes the disorder into account in numerical simulations and validate it using experimental data.
View Article and Find Full Text PDFWe propose a simple and flexible fabrication approach based on the moiré effect of photoresist gratings for rapid synthesis of apodized structures with continuously varying depth. Minor modifications in a standard laser interference lithography setup allow creating macroscopic, visible by naked eye moiré patterns that modulate the depth of subwavelength diffraction gratings. The spatial frequency of this modulation is easily controlled in a wide range, allowing to create a quasicrystal in extreme cases.
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