ABSTRACT
This article describes fiber optic and electrochemical pH sensors that could become part of a therapeutic arsenal to quickly and aggressively treat stroke victims as well as people who have suffered brain trauma. The fiber optic sensor design was based on the immobilization of a pH-sensitive dye, seminaphthorhodamine-1 carboxylate (SNARF-1C), onto the end of a 125-microm-diameter silica optical fiber using the sol-gel method. A miniature bench-top fluorimeter system was developed for use with the optical fiber to obtain pH measurements. The electrochemical sensor was based on sputter-coated iridium oxide thin films. Linear and reproducible responses for both sensors were obtained in human blood with pH varying between 6.8 ato 8.0, which encompasses the clinically relevant range. In vivo studies were also performed and results indicated that both types of sensors tracked pH with very little drift.
Subject(s)
Biosensing Techniques , Brain Chemistry , Animals , Brain/physiology , Brain/physiopathology , Electrochemistry/instrumentation , Electrochemistry/methods , Equipment Design , Fiber Optic Technology/instrumentation , Fiber Optic Technology/methods , Humans , Hydrogen-Ion Concentration , Monitoring, Physiologic/methods , Optical Fibers , Rats , Rats, Sprague-Dawley , Sodium Bicarbonate/administration & dosage , Stroke/physiopathologyABSTRACT
The application of microelectromechanical systems (MEMS) to medicine is described. Three types of biomedical devices are considered, including diagnostic microsystems, surgical microsystems, and therapeutic microsystems. The opportunities of MEMS miniaturization in these emerging disciplines are considered, with emphasis placed on the importance of the technology in providing a better outcome for the patient and a lower overall health care cost. Several case examples in each of these areas are described. Key aspects of MEMS technology as it is applied to these three areas are described, along with some of the fabrication challenges.