The efficacy of cell-based therapy depends on the function and survival of transplanted cells, which have been suggested to be enhanced by spheroid formation. However, few attempts at spheroid generation from insulin-secreting cells, which may be used to treat type 1 diabetes, have been reported. We therefore developed spheroids from the mouse insulinoma cell line NIT-1 by using polydimethylsil...

Micropatterning of hydrogels is potentially useful for a variety of applications, including tissue engineering, fundamental biological studies, diagnostics, and high-throughput screening. Although synthetic polymers have been developed for these applications, natural polymers such as polysaccharides may have advantages for biological samples and cell-based devices because they are natural compo...

A novel micropattern-assisted nanoassembly (μPAN) method to organize highly ordered nanocolloidal arrays onto a nonfouling polymeric surface is reported. A high-density array of polyethylene glycol (PEG) hydrogel microwells is first fabricated on glass substrates with the minimal feature resolution of 1 μm using photolithography method. By simply controlling the colloidal concentration of the d...

A paper-based colorimetric biosensor suitable for point-of-care bioassay of blood samples is developed using highly stable enzyme thin-film coatings confined within inkjet printed polymeric microwells. The microwells are developed through a simple one-step inkjet printing of hydrophobic polystyrene on paper, with walls formed by the polymer that fills the gaps inside the paper body. The microwe...

A microfluidic device containing arrays of microwells filled with microbead sensors was used to perform protein assays in a saliva sample. Techniques for the fabrication of fully integrated arrays of microwells within polydimethylsiloxane (PDMS) microchannels were demonstrated. Subsequent microwell loading with stochastic arrays of encoded microbeads was performed and the devices were used for ...

We present a novel method for the isolation, functional analysis and sorting of single cells or small cellular aggregates. Inverted open microwells featuring a microchannel on top, an open air-fluid interface on bottom side and embedded electrodes were implemented on flexible-PCB technology. Microwell arrays in pitch with standard microtiter plates were implemented. K562 cells were delivered to...

We present a novel strategy for patterning single magnetic beads by using digital microfluidics (DMF). A droplet containing a suspension of superparamagnetic particles is transported back and forth over an array of femtoliter-sized microwells by using electrowetting-on-dielectric actuation forces. Compared to existing methods, this technique allows patterning of superparamagnetic beads in micro...

This paper describes a new platform for the capture, perfusion, and imaging of a large number of dissociated olfactory sensory neurons (OSNs) simultaneously. The platform consists of a fluid selection device integrated with a multiwell plate and a removable-top cell perfusion chamber bonded to an array of addressable cell-trapping microwells. Integration of a 24well plate with our PDMS device a...

This paper presents a highly efficient single cell capture scheme using hydrodynamic guiding structures in a microwell array. The implemented structure has a capturing efficiency of >80%, and has a capacity to place individual cells into separated microwells, allowing for the time-lapse monitoring on single cell behavior. Feasibility was tested by injecting microbeads (15 μm in diameter) and pr...