A SOL-GEL BASED FIBER OPTIC SENSOR FOR LOCAL BLOOD-PH MEASUREMENTS

This paper describes a fiber optic pH sensor based upon sol-gel encaps ulation of a self-referencing dye, seminaphthorhodamine-1 carboxylate (SNARF-1C). The simple sol-gel fabrication procedure is ideal for enca psulation and immobilization of dye molecules onto the end of an optic al fiber. A miniature bench-top fluorimeter system was developed for u se with the optical fiber to obtain pH measurements. Linear and reprod ucible responses were obtained in human blood in the pH range 6.8-8.0, which encompasses the clinically-relevant range. The sensor was also shown to have low coating leachability. This sensor will be used as pa rt of an array of sensors being developed to monitor stroke patients. (C) 1997 Elsevier Science S.A.