Large area real-time system for screening DNA libraries

A nuclear imaging system based on a position-sensitive photomultiplier tube (PSPMT) and scintillating fiber optics is described. A real-time, large-area imaging system has been constructed and tested using realistic phantoms and biological samples. This prototype, which has an active area of 112 cm² was found to be more than 100 times more sensitive for detection of ³²P radiation than film and provided a spatial resolution of approximately 1.7 mm. By choosing suitable fiber dimensions and packing methods on the PSPMT this system is capable of producing images over an area equal to X-ray film and with spatial resolution approaching 0.5 mm. The digital nature of the image allows a great deal of freedom in processing and displaying data, including automatic identification and location of the desired features