Phase-sensitive multichannel detection system for chemical and biosensor arrays and fluorescence lifetime-based imaging

Abstract

Fluorescence lifetime-based sensors are attractive candidates to satisfy the demand for chemical detection and monitoring in medical, pharmaceutical, and environmental applications. In many cases it is desirable not only to monitor one particular chemical or biological species, but several simultaneously. In this work, we have focused our efforts on the development of a detection platform for multianalyte sensor arrays that is able to monitor changes in the fluorescence lifetimes corresponding to the presence of many analytes of interest in real time. We describe a new version of the multichannel, phase-sensitive electronic detection system employing a multianode photomultiplier tube, light emitting diodes, laser diodes, custom-built detection electronics, and a software package. This system utilizes the frequency-domain method of time-resolved spectroscopy. The present 16-channel prototype of the device is compact and assembled from inexpensive, off-shelf components. Future detection systems may be expected to monitor simultaneously at least up to 63 signals from separate chemical and biosensors. The system is also suitable for lifetime-based imaging. The capabilities of this system are demonstrated with several examples, including a pH-sensitive sensor array measurement and lifetime-based imaging of spatially distributed chemical reactions. © 2000 American Institute of Physics.