Molecular imaging probes and relevance of our research. Microscopy of tissue samples has traditionally been one of the mainstays of experimental biology. However, advances in our understanding of the biochemical basis of disease has made it desirable and even necessary to be able to image these changes as they happen in vivo, using techniques which are noninvasive. The goal of such techniques are several fold:1) to obtain, analyze, and monitor disease related changes in molecular physiology over time and with high spatial resolution, i.e., up to the level of individual cells,2) to simultaneously acquire highly accurate anatomical images (tissue mapping) while mapping the functional status of tissues and organs, and3) to allow fundamental research findings to be translated into clinically diagnostic imaging strategies.Towards this end, ‘molecular imaging’ utilizes signals from endogenous or exogenous (chemically engeneered) substrates to probe chemical reactions in living cells. Such ‘reporters’ or ‘sensors’ have been successfully used to track real time changes in molecular physiology using modern diagnostic imaging methods such as magnetic resonance imaging (MRI), positron emission tomography (PET), gamma scintigraphy, optical fluorescence and near-infrared imaging, to relate these changes to the initiation and progression of diseases such as atherosclerosis and cancer. In order to gain wide-spread use in a clinical setting, molecular probes must be biocompatible, easily administered, specific and effective at low dosages.Our research addresses the issue of increasing selectivity and sensitivity of imaging probes. We also apply this research in realistic models of diseases.