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In this paper, we report on the first laser-micromachined batch-fabricated single-layer elastomeric actuator with a corrugated surface profile. The structural material of the cantilever actuator is a single [polydimethylsiloxane (PDMS)] layer, and electrodes are soft lithographically patterned conductive carbon grease. The asymmetric corrugated surface provides a bending moment in a single PDMS layer without the need for a second inactive layer. An actuator which is 5 mm long, 1 mm wide, and 80 \mu\m thick can generate up to 2-mm out-of-plane displacement with zero applied force and 15 \mu\N at zero deflection while consuming 20 \mu\W of static power when actuated with 500 V. \hfill[2011-0159] [ABSTRACT FROM AUTHOR]

In this paper, we present an ultrasonically powered implantable micro-oxygen generator (IMOG) that is capable of in situ tumor oxygenation through water electrolysis. Such active mode of oxygen generation is not affected by increased interstitial pressure or abnormal blood vessels that typically limit the systemic delivery of oxygen to hypoxic regions of solid tumors. Wireless ultrasonic powering (2.15 MHz) was employed to increase the penetration depth and eliminate the directional sensitivity associated with magnetic methods. In addition, ultrasonic powering allowed for further reduction in the total size of the implant by eliminating the need for a large area inductor. IMOG has an overall dimension of 1.2 mm × 1.3 mm × 8 mm, small enough to be implanted using a hypodermic needle or a trocar. In vitro and ex vivo experiments showed that IMOG is capable of generating more than 150 μA which, in turn, can create 0.525 μL/min of oxygen through electrolytic disassociation. In vivo experiments in a well-known hypoxic pancreatic tumor models (1 cm ^3 in size) also verified adequate in situ tumor oxygenation in less than 10 min. [ABSTRACT FROM PUBLISHER]