Liquid surface established by standing waves is used as a dynamically reconfigurable template to assemble microscale materials into ordered, symmetric structures in a scalable and parallel manner. We illustrate broad applicability of this technology by assembling diverse materials from soft matter, rigid bodies, individual cells, cell spheroids and cell-seeded microcarrier beads.

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Single oocyte manipulation in microfluidic channels via precisely controlled flow is critical in microfluidic-based in vitro fertilization. Such systems can potentially minimize the number of transfer steps among containers for rinsing as often performed during conventional in vitro fertilization and can standardize protocols by minimizing manual handling steps. To study shape deformation of oocytes under shear flow and its subsequent impact on their spindle structure is essential for designing microfluidics for in vitro fertilization. Here, we developed a simple yet powerful approach to (i) trap a single oocyte and induce its deformation through a constricted microfluidic channel, (ii) quantify oocyte deformation in real-time using a conventional microscope, and (iii) retrieve the oocyte from the microfluidic device to evaluate changes in their spindle structures. We found that oocytes can be significantly deformed under high flow rates, e.g., 10 μl/min in a constricted channel with a width and height of 50 and 150 μm, respectively. Oocyte spindles can be severely damaged, as shown here by immunocytochemistry staining of the microtubules and chromosomes. The present approach can be useful to investigate underlying mechanisms of oocyte deformation exposed to well-controlled shear stresses in microfluidic channels, which enables a broad range of applications for reproductive medicine.

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Nanocomposite AEMs consisting of QPSF and GO or DGO showed improved alkaline solution stabilities.

Inspired by the complex biophysical processes of cell adhesion and detachment under blood°ow in vivo, numerous novel micro°uidic devices have been developed to manipulate, capture, and separate bio-particles for various applications, such as cell analysis and cell enumeration. However, the underlying physical mechanisms are yet unclear, which has limited the further development of micro°uidic devices and point-of-care (POC) systems. Mathematical modeling is an enabling tool to study the physical mechanisms of biological processes for its relative simplicity, low cost, and high e±ciency. Recent development in computation technology for multiphase°ow simulation enables the theoretical study of the complex°ow processes of cell adhesion and detachment in micro°uidics. Various mathematical methods (e.g., front tracking method, level set method, volume of°uid (VOF) method,°uidÀsolid interaction method, and particulate modeling method) have been developed to investigate the e®ects of cell properties (i.e., cell membrane, cytoplasma, and nucleus),°ow conditions, and microchannel structures on cell adhesion and detachment in micro°uidic channels. In this paper, with focus on our own simulation results, we review these methods and compare their advantages and disadvantages for cell adhesion/detachment modeling. The mathematical approaches discussed here would allow us to study micro°uidics for cell capture and separation, and to develop more e®ective POC devices for disease diagnostics.