3D-Printed Micro-Lattice Gold Electrode for Evaluating Reagent Gradual Release Properties

In this study, we propose a device for evaluating reagent gradual release using a 3D-printed micro-lattice structure coated with electroless Ni/Au plating. Conventional techniques had difficulty evaluating the detailed time-dependent changes in the release rate of reagents, whereas the proposed device enables precise evaluation of the retention and release of reagents. To create a device to evaluate the release properties, a micro-lattice structure was fabricated with a lattice design featuring 30 <tex xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">$\mu \mathrm{m}$</tex> square openings, composed of pillars with a diameter of 10 <tex xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">$\mu \mathrm{m}$</tex>. The structure was arranged with a width of 500 <tex xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">$\mu\mathrm{m}$</tex>, a length of 1 mm, and a height of 250 <tex xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">$\mu \mathrm{m}$</tex> at the tip of the electrode. The surface of the structure was coated by electroless plating to create a 3D electrode. A target reagent was held in the 3D electrode and then released. The release properties were evaluated by electrochemical measurements, and the effectiveness of the proposed 3D micro-lattice electrode was demonstrated.