The present invention provides compositions providing and methods using fluorescence detection device, comprising an electroluminescent light (EL) source, for measuring fluorescence in biological samples. In particularly preferred embodiments, the present invention provides an economical, battery powered and Hand-held device for detecting fluorescent light emitted from reporter molecules incorporated into DNA, RNA, proteins or other biological samples, such as a fluorescence emitting biological sample on a microarray chip. Further, a real-time hand-held PCR Analyzer device comprising an EL light source for measuring fluorescence emissions from amplified DNA is provided.