A Magnetically Controlled Wireless Intraocular Oxygen Sensor: Concept, Prototype, and In Vitro Experiments

The influence of oxygen on various ophthalmologic complications is not completely understood and intraocular oxygen measurements are essential for better diagnosis and treatment. A magnetically controlled wireless sensor device is proposed for minimally invasive intraocular oxygen concentration measurements. This device will make it possible to make measurements at locations that are currently too invasive for human intervention by integrating a luminescence optical sensor and a magnetic steering system. The sensor works based on quenching of luminescence in the presence of oxygen. A novel iridium phosphorescent complex is designed and synthesized for this system. A frequency-domain lifetime measurement approach is employed because of the intrinsic nature of the lifetime of luminescence. Experimental results of the oxygen sensor are presented to demonstrate the concept. In order to use this sensor for in vivo intraocular applications, the size of the sensor must be reduced, which will require an improved signal-to-noise ratio.