Publications by authors named "Ethan G Keeler"

Cell manipulation is one of the most impactful applications for optical tweezers, and derived from this promise, we demonstrate a new optical tweezers system for the study of cell adhesion and organization. This method utilizes photonic-crystal-enhanced optical tweezers to manipulate cells with low laser intensities. By doing so, it enables effective cell patterning and culturing within the conditions necessary for successful differentiation and colony formation of human pluripotent stem cells.

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We propose and demonstrate a new optical trapping method for single cells that utilizes modulated light fields to trap a wide array of cell types, including mammalian, yeast, and Escherichia coli cells, on the surface of a two-dimensional photonic crystal. This method is capable of reducing the required light intensity, and thus minimizing the photothermal damage to living cells, thereby extending cell viability in optical trapping and cell manipulation applications. To this end, a thorough characterization of cell viability in optical trapping environments was performed.

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This paper describes an endoscopic-inspired imaging system employing a micro-electromechanical system (MEMS) micromirror scanner to achieve beam scanning for optical coherence tomography (OCT) imaging. Miniaturization of a scanning mirror using MEMS technology can allow a fully functional imaging probe to be contained in a package sufficiently small for utilization in a working channel of a standard gastroesophageal endoscope. This work employs advanced image processing techniques to enhance the images acquired using the MEMS scanner to correct non-idealities in mirror performance.

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