Connected Droplet Shape Analysis for Nanoflow Quantification in Thin Electroosmotic Micropumps and a Tunable Convex Lens Application.

Thin electroosmotic flow (EOF) micropumps can generate flow in confined spaces such as lab-on-a-chip microsystems and implantable drug delivery devices. However, status quo methods for quantifying flow and other important parameters in EOF micropumps depend on microfluidic interconnects or fluorescent particle tracking: methods that can be complex and error-prone. Here, we present a novel connected droplet shape analysis (CDSA) technique that simplifies flow rate and zeta potential quantification in thin EOF micropumps.

Progress on Designing a Chemical Retinal Prosthesis.

The last major review of progress toward a chemical retinal prosthesis was a decade ago. Many important advancements have been made since then with the aim of producing an implantable device for animal testing. We review that work here discussing the potential advantages a chemical retinal prosthesis may possess, the spatial and temporal resolutions it might provide, the materials from which an implant might be constructed and its likely effectiveness in stimulating the retina in a natural fashion.

Metrology and characterization of SU-8 microstructures using autofluorescence emission.

Sophisticated three-dimensional microstructures fabricated using the negative tone SU-8 photoresist are used in many biomedical and microfluidic applications. Scanning electron microscopy (SEM) and profilometry are commonly used metrological techniques for the dimensional characterization of fabricated SU-8 microstructures but are not viable for non-destructive measurements and characterization of subsurface features like hidden microchannels. In this study, we report a unique methodology for the non-destructive dimensional characterization of SU-8 microstructures using the emitted autofluorescence radiation from fabricated SU-8 microstructures to generate depth profiles.

Novel imaging technique for non-destructive metrology and characterization of ultraviolet-sensitive polymeric microstructures.

The negative photoresist SU-8 has attracted much research interest as a structural material for creating complex three-dimensional (3D) microstructures incorporating hidden features such as microchannels and microwells for a variety of lab-on-a-chip and biomedical applications. Achieving desired topological and dimensional accuracy in such SU-8 microstructures is crucial for most applications, but existing methods for their metrology, such as scanning electron microscopy (SEM) and optical profilometry, are not practical for non-destructive measurement of hidden features. This paper introduces an alternative imaging modality for non-destructively characterizing the features and dimensions of SU-8 microstructures by measuring their transmittance of 365 nm ultraviolet (UV) light.