Optical tweezers system for live stem cell organization at the single-cell level.

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. To this end, the biocompatibility of plasma-treated parylene-C for cell culturing was studied, and a thorough characterization of cellular interactive forces was performed using this system. Furthermore, this study also demonstrates construction of patterned cell arrays at arbitrary positions with micrometer-scale precision.