sentence: LMWP , with sequence of VSRRRRRRGGRRRR , was later found that it bears potent cell penetration ability , and are able to mediate delivery of peptides ,43 proteins ,31 , 44 gene ,44 , 45 and nanoparticles.28 , 46 More importantly , it safety has been undergone scrutiny investigation both in vitro and in vivo ( using dogs ) .47 , 48 Therefore , LMWP has been explored as both a CPP and a heparin-binding ligand in the prodrug-type delivery system design.It should be pointed out that , however , heparin also possesses a strong affinity to plasma antithrombin III ( AT ) , a mechanism that accounts for its anti-clotting function .