Conference Paper

Toward Targeted Retinal Drug Delivery with Wireless Magnetic Microrobots

Inst. of Robot. & Intell. Syst., ETH Zurich, Zurich
DOI: 10.1109/IROS.2008.4650768 Conference: 2008 IEEE/RSJ International Conference on Intelligent Robots and Systems, September 22-26, 2008, Acropolis Convention Center, Nice, France
Source: DBLP


Retinal vein occlusion is an obstruction of blood flow due to clot formation in the retinal vasculature, and is among the most common causes of vision loss. Currently, the most promising therapy involves injection of t-PA directly into small and delicate retinal vessels. This procedure requires surgical skills at the limits of human performance. In this paper, targeted retinal drug delivery with wireless magnetic microrobots is proposed. We focus on four fundamental issues involved in the development of such a system: biocompatible coating of magnetic microrobots, diffusion-based drug delivery, characterization of forces needed to puncture retinal veins, and wireless magnetic force generation. We conclude that targeted drug delivery with magnetic microrobots is feasible from an engineering perspective, and the idea should now be explored for clinical efficacy.

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    • "Four elliptical microrobot pieces of length 900 µm, width 450 µm, and thickness 50 µm are used as the magnetic platform holding the coating. The pieces are made from electroplated nickel and then coated with titanium for biocompatibility as described in [21]. The pieces are sterilized in ethanol and then washed with sterilized DI-water. "
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