Current state of in vivo panning technologies: Designing specificity and affinity into the future of drug targeting.

Targeting ligands are used in drug delivery to improve drug distribution to desired cells or tissues and to facilitate cellular entry. In vivo biopanning, whereby billions of potential ligand sequences are screened in biologically-relevant and complex conditions, is a powerful method for identification of novel target ligands. This tool has impacted drug delivery technologies and expanded our arsenal of therapeutics and diagnostics. Within this review we will discuss current in vivo panning technologies and ways that these technologies can be improved to advance next-generation drug delivery strategies.