Optimizing Ligand Valency to Maximize Tendon Accumulation of Peptide-Targeted Nanoparticles.

In many tissues, including musculoskeletal tissues such as tendon, systemic delivery typically results in poor targeting of free drugs. Hence, we previously developed a targeted drug delivery nanoparticle (NP) system for tendon healing, leveraging a tartrate resistant acid phosphatase (TRAP) binding peptide (TBP) ligand. The greatest tendon targeting was observed with NPs functionalized with 30 000 TBP ligands per NP at day 7 during the proliferative healing phase, relative to the inflammatory (day 3) and early remodeling (day 14) phases of healing.