Capillarity and Wetting Phenomena: Drops, Bubbles, Pearls, Waves

Electrospinning: A versatile technique for making of 1D growth of nanostructured nanofibers and its applications: an experimental approach

Nanofibers of naturally modified polymer such as carboxymethyl cellulose (CMC) blended with poly(vinyl alcohol) (PVA) at different ratios was obtained by electrospinning technique. The blended solutions of CMC and PVA loaded with and without diclofenac sodium (DS) were electrospun using environmentally benign electrospinning technique in the absence of organic solvents. Scanning electron microscopy (SEM), Fourier transform infrared (FTIR), thermogravimetric analysis (TGA) were used to investigate the surface morphology functional groups, as well as the thermal stability of DS loaded CMC/PVA nanofibers mat. The mechanical properties of the as prepared electrospun nanofibers was also evaluated. The entrapment efficiency and the in vitro release of DS loaded CMC/PVA nanofibers were characterized using UV-Vis spectroscopy. The obtained results displayed that the blended nanofibers have shown a smooth morphology, no beads formation when the concentration of CMC was equal or below 5% and beads formation...

Preparation of biocompatible system based on electrospun CMC/PVA nanofibers as controlled release carrier of diclofenac sodium

Thermal Optofluidics: Principles and Applications

Advances in engineering near-infrared luminescent materials.

This study makes a claim of utilizing the photothermal effect of graphene oxide nanosheets (GONs) to effectively produce various microbubbles in an optical microfiber system at infrared optical communications band. A low power continuous-wave light at wavelength of 1527-1566 nm was launched into the microfiber to form GONs-deposition which acted as a linear heat source for creating various microbubbles. Both thermal convection flow and optical gradient force were responsible for the driving force to assemble GONs onto the microfiber. This simple optical fiber system can be used for assembling other micro/nanoscale particles and biomolecules, which has prospective applications in sensing, microfluidics, virus detection, and other biochip techniques.

Graphene oxide-deposited microfiber: a new photothermal device for various microbubble generation

The realization of directional and controllable delivery of massive mesoscopic matters is of great significance in the field of microfluidics. Here, the mobile thermocapillary vortex array has achieved the enrichment and transport of massive mesoscopic matters in free or limited space. The ability of the vortex array to confine objects in the center ensures the controllability of particle trajectory. We also simulated the delivery process to reveal the stability of the mobile vortex. Owing to the distance between the vortex center and the heat source, the method provides the ability to protect trapped matters, including organisms and living cells. The mobile vortex array has opened the exciting possibilities of realizing that bridges the gap between remote optofluidics and lab on a chip.

Optofluidic trapping and delivery of massive mesoscopic matters using mobile vortex array

A convenient and easily controllable microfluidic system was proposed based on a photothermal device. Here, graphene oxide was assembled on an optical waveguide, which could serve as a miniature heat source to generate a microbubble and to control dynamic behaviors of flow by adjusting optical power at the micrometer scale. Micro/nanoparticles were used to demonstrate the trace of fluid flow around the microbubble, which displayed the ability of the flow to capture, transmit, and rotate particles in thermal convection. Correspondingly, three-dimensional theoretical simulation combining thermodynamics with hydrodynamics analyzed the distribution of the velocity field induced by the microbubble for collection and driving of particles. Furthermore, the photothermal waveguide would be developed into a microbubble-based device in the manipulation or transmission of micro/nanoparticles.

Microbubble-assisted optofluidic control using a photothermal waveguide

Thermal microbubbles generally grow directly from the heater and are spherical to minimize surface tension. We demonstrate a novel type of microbubble indirectly generated from a graphene oxide-microheater. Graphene oxide's photothermal properties allowed for efficient generation of a thermal gradient field on the microscale. A series of approximately ellipsoidal microbubbles were generated on the smooth microwire based on heterogeneous nucleation. Other dynamic behaviors induced by the microheater such as constant growth, directional transport and coalescence were also investigated experimentally and theoretically. The results are not only helpful for understanding the bubble dynamics but also useful for developing novel photothermal bubble-based devices.

/pdf/dynamic-behaviors-of-approximately-ellipsoidal-microbubbles-19z53hmobi.pdf

Dynamic behaviors of approximately ellipsoidal microbubbles photothermally generated by a graphene oxide-microheater

© 2012 Xing et al., licensee InTech. This is an open access chapter distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/3.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. Subwavelength and Nanometer Diameter Optical Polymer Fibers as Building Blocks for Miniaturized Photonics Integration

/pdf/subwavelength-and-nanometer-diameter-optical-polymer-fibers-57fnoj6bcl.pdf

Debin Zhu

Papers

Graphene oxide-deposited microfiber: a new photothermal device for various microbubble generation

Optofluidic trapping and delivery of massive mesoscopic matters using mobile vortex array

Microbubble-assisted optofluidic control using a photothermal waveguide

Dynamic behaviors of approximately ellipsoidal microbubbles photothermally generated by a graphene oxide-microheater

Subwavelength and Nanometer Diameter Optical Polymer Fibers as Building Blocks for Miniaturized Photonics Integration