Lecture 15: Stealth' particles Last time Nano- and micro-particle carriers Today Delivery of drugs to tissue from circulation stealth particles theory and function Reading S. Stolnik et al. 'Long circulating microparticulate drug carriers, Adv. Drug. Deliv. Rev 16,195(1995) Delivery of drugs to tissues via systemic circulation

Lecture 16: Intracellular drug delivery Last time nano- and micro-particle drug carriers Delivery to tissues from systemic circulation Today. Intracellular drug delivery Reading A.S. Hoffman et aL., Design of \smart polymers that can direct intracellular drug delivery, Polym. Adv. Technol. 13, 992-999(2002) Ph gradients and drug delivery: cancer res. 56, 1194(1996): adv drug deliv rev 25, 3 (1997); see asokan minireview

Lecture 13: Molecular Devices Last time biological strategies for inorganic templating by organic materials Biomimetic organic template materials Biomimesis of bone Today Reading V Vogel, 'Reverse engineering: Learning from proteins how to enhance the performance

molecular switches Proteins as motors in nanodevices Today. nano-and micro-particle drug carriers Reading D A Hammer and D.E. Discher, ' Synthetic cells- Self-assembling polymer membranes and bioadhesive colloids, Annu. Rev. Mater Res, 31, 387-404 (2001) Nano- and Micro-scale Drug Carriers and Detection Reagents Nano- to Micro-particle polymer-protein

Lecture 11: Molecular Design and Synthesis of Biomaterials Il: Inorganic Biomaterials Last time: hydrogel applications: molecular imprinting and responsive drug delivery Today biomineralization and biomimetic inorganic/organic composites Inorganic biomaterials Reading L A. Estroff and A D. Hamilton, ' At the interface of organic and inorganic chemistry

Molecular switches in the cell: fibronectin as a mechanical switch (vogel, 2002) Fibronectin is an adhesion protein secreted by cells and assembled into fibrils to support adhesion and migration Composed of\ of fibronectin repeats Fnl, Fnll, and Fnlll connected by short linkers of varying flexibility One particular Fnlll repeat, Fnlll10

Lecture 12: Organic templating of inorganic materials and bone biomimesis Last time interfacial biomineralization and biomimetic inorganic chemistry Today biological strategies for inorganic templating by organic materials Biomimetic

Brannon-Peppas theory of swelling in ionic hydrogels Original theory for elastic networks developed by Flory and Mehrer, refined for treatment of ionic hydrogels by Brannon-Peppas and Peppas Other theoretical treatments Derivation of ionic hydrogel swelling Model structure of the system

Hydrogels in drug delivery Control of drug release kinetics by hydrogel structure6, Release from stable hydrogels is controlled by diffusion of solute through the network Diffusion is described by Fick,s second law

Lecture 8: Physical Hydrogels Last Day Overview of biomedical applications of hydrogels Structure of covalent hydrogels Thermodynamics of hydrogel swelling Today Bonding in physical hydrogels Structure and thermodynamics of block copolymer hydrog Reading