Biodegradable materials and control release I

What are polymers synthesized from

Glycolic acid

Why would a medical practitioner like a material to degrade in the body?

Does not require second surgery, avoids stress shielding, Offers drug delivery

List 4 natural polymers

Fibrin, Collagen, Gelatin, Chitosan

List 4 Synthetic polymers

PLA, PGA, PLGA, PCL

Why are synthetic polymers better?

Tailorable properties, predictable, no concern of immune system, reliable source of raw materials

What are the 2 types of Degradation mechanisms?

Hydrolysis(homogenous and Heterogenous), and Enzymatic

What are the 4 steps of Degradation?

Water absorption, reduction of mechanical properties, then molar mass, then weight loss.

What are 2 types of Degradation Schemes?

Surface erosion(Layer by layer) and bulk degradation.

What are the 3 types of fabrication for forming drug eluting polymer?

Compressive and Melt Molding, Solvent casting

What are the Advantages and Disadvantages of melt molding/casting

It is more uniformed distribution and can be widely shaped, but it can force polymers and drugs to interact at high temperatures and it costs a lot.

What are the steps of Solvent casting

Co-dissolve drug and polymer in organic solvent, pour it into a mold under dry ice, then let solvent evaporate.

What are advantages and disadvantages of Solvent Casting

Simple, at room temp, but it is not uniformed distribution and fragile with solvent residue that can remain.

What are 4 Biodegradable polymers uses

Wound management, Dental, Orthopedic devices, and cardiovascular applications

What are 5 factors that influence degradation behavior?

Chemistry, Materials, Manufacturing, biology, and Structure

What are 4 factors that accelerate Polymer Degradation?

more Hydrophilic back bones or end groups, Low crystallinity, More porosity, Smaller Device Size