LUMINESCENCE CHEMICAL SENSORS FOR BIOMEDICAL APPLICATIONS - SCOPE AND LIMITATIONS

A great variety of fluorescence-based sensors, sensitive to heat, ions, enzyme substrates and gases, are known. Fluorescence-based measurement systems have been developed for in vitro and in vivo monitoring of blood gases. Optical pH sensors have been used for monitoring carbon dioxide through induced changes of pH. Oxygen fluorescence sensors have been based on intensity measurements and on measurements of fluorescence lifetime. Enzymatically selective layers use oxygen or pH sensors as transducers. Fluorescence-based sensors for sensing ionic species have also been investigated. The basic technology, performance characteristics and design parameters of specific optical sensors are discussed. Examples illustrate the current limitations of fluorescence-based optical sensors, especially when used for biomedical applications.