BEH.462/3.962J Molecular Principles of Biomaterials Spring 2003 人人人 AAA 5 Min aleutian f PE J ahy seg 人八人·mkwm Cr-cionis segment (Kakizawa and Kataoka, 2002) o Composition range for core-shell structure? Vesicle carriers o Mechanisms of cargo delivery Membrane fusion Receptor-mediated endocytosis(internalization by cell) o Functionalizing liposomes o' stealth’ functions o limitations difficulty in storage/stability rapid drug leakage(T M. Allen, Drugs 54 suppl. 4, 8-14 (1997) unstable drug entrapment hydrophobic drugs interact with bilayer and destabilize structure drug instability within liposomes porymerosom unmodin Droteins interact with bilayer and become denatured fied liposomes activate complement causes pseudo-allergic reactions that damate heart and liver cells o larger amphiphilic molecules than lipids larger hydrophobic blocks increase membrane stability and mechanical strength can be polymerized to make membrane associations covalent Lecture 14-nano- and micro-particles 4 of 6BEH.462/3.962J Molecular Principles of Biomaterials Spring 2003 (Kakizawa and Kataoka, 2002) o Composition range for core-shell structure? Vesicle carriers ƒ Liposomes o Mechanisms of cargo delivery ƒ Membrane fusion ƒ Receptor-mediated endocytosis (internalization by cell) o Functionalizing liposomes o ‘stealth’ functions o limitations ƒ difficulty in storage/stability ƒ rapid drug leakage (T.M. Allen, Drugs 54 suppl. 4, 8-14 (1997)) x unstable drug entrapment x hydrophobic drugs interact with bilayer and destabilize structure ƒ drug instability within liposomes x proteins interact with bilayer and become denatured ƒ unmodified liposomes activate complement 5 x causes pseudo-allergic reactions that damate heart and liver cells ƒ polymerosomes o larger amphiphilic molecules than lipids ƒ larger hydrophobic blocks increase membrane stability and mechanical strength ƒ can be polymerized to make membrane associations covalent Lecture 14 – nano- and micro-particles 4 of 6