Lecture 19: Biosensors(continued ast time: biosensor device cla Gene array biosensor Today detection methods Detection Elements Macroscopic fluorescence, diffraction, or interference ·what Example: quantum dot-loaded microsphere capture agents QDs show size-dependent luminescence Narrow emission bands from a common excitation wavelength

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

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

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

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

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

Lecture 10: Bioengineering applications of hydrogels: Molecular Imprinting and Drug Delivery Last Day polyelectrolyte gels Polyelectrolyte complexes and multilayers Applications in bioengineering Theory of ionic gel swelling Toda Molecular imprinting

Lecture 7: Hydrogel Biomaterials: Structure and Physical Chemistry Last Day: programmed/regulated/multifactor controlled release for drug delivery and tissue engineering

Lecture 5: Controlled Release Devices Last time: Using enzyme substrate and cytokine peptides to engineer biological recognition of synthetic polymers Today: principles of controlled release devices based on degradable polymers Synthesis of controlled release devices Theory of polymer-based controlled release

Molecular Principles of Biomaterials Spring 2003 Lecture 2: Molecular Design and Synthesis of Biomaterials I: Biodegradable Materials Chemistry of Biodegradable Materials Hydrolytically degraded biomaterials Common hydrolytically unstable linkages Ester