The Role of Molecular Imaging in Drug Delivery.

The parallel development of molecular imaging and drug delivery allows the combination of therapeutic agents with imaging moieties, which facilitates visualisation of the drug delivery process and provides a realtime readout on the efficacy of a therapeutic agent. Although challenging, it is feasible to construct a highly versatile, multifunctional single 'theranostic' probe for quantitative molecular imaging, targeted drug delivery and controlled drug release to obtain an effective therapeutic response. Compared with conventional methods for the evaluation of pharmacokinetics/pharmacodynamics, molecular imaging has advantages such as substantially decreasing the workload and increasing the volume of more precise data with statistical relevance. More importantly, molecular imaging techniques bridge the gap between pre-clinical and clinical research to develop candidate drugs that have the optimal target specificity, pharmacodynamics and efficacy. With the advancement and integration of technology in various fields, diverse types of targeted imaging probe coupled with drug delivery potential have been developed. Preliminary data have demonstrated that it is feasible and promising to use these targeted carriers for simultaneous target imaging and drug delivery.