Abstract

We report of the development of optical coatings for use in an artificial lung (photolytic artificial lung – PAL). The unrelenting nature of chronic lung disease has long energized the pulmonary community to seek technologies to replicate the capacity of the lungs to exchange oxygen for carbon dioxide. While most such artificial lung technologies work by delivering oxygen to the blood through a system of hollow fibers or tubes, our approach employs photolytic energy to generate oxygen from the water already present in blood, thus eliminating the need for gas delivery. We have previously demonstrated that it is feasible to generate dissolved oxygen (DO) directly from the water content of synthetic serum, based on the interaction of UV light with a highly absorbent TiO₂ surface. In the current study, we sought to extend this work by using photolytic energy to generate DO from whole blood, thus providing an increase of oxyhemoglobin as a function of TiO₂ surface illumination. In these experiments, mixed arterial-venous bovine blood was flowed in a re-circulating loop over a nanocrystalline TiO₂ thin film at 80 ml/min. Following light exposure, the fraction of oxy-hemoglobin in the blood increased from 83% to 92% (near saturation), and remained stable throughout the trial period (approximately 5.5 hours). The fraction of dissolved oxygen contained in the water phase of the blood increased in a parallel manner with oxyhemoglobin as a result of light induction, indicating that near complete oxygenation of the blood's hemoglobin content was achieved. We conclude that it is feasible to photolytically oxygenate the hemoglobin contained in whole blood with oxygen derived from the blood's own water content.

© 2004 Optical Society of America