Lecture 2 Flashcards - Natural Polymers BME 515

What is the difference between traditional vs functional medicine (and what is the con of functional medicine)

Traditional - Typical doctors addressing symptoms with science but not always the root cause

Functional - Why are the symptoms there and how we can solve it (the biggest con is price point, since its not covered by insurance)

What are some advantages of synthetic polymers?

1. Easily manufactured

2. Properties are consistent and predictable (bc they are manmade)

3. Stronger mechanical properties

4. Cost

What are the disadvantages of Synthetic polymers?

1. Biocompatibility can be limited (bc it is manmade)

2. Properties similar to the body often have shortcomings

3. Bioactivity

4. Complex synthesis process

5. Byproducts (of manufacturing)

What are advantages of Natural polymers?

1. Biocompatibility

2. Bioresorbable

3. Versatile

4. Bioactive

What are some disadvantages of natural polymers?

1. Mechanical strength

2. Processing

3. Variability

What are the following used for:

• Bee Venom

• Fenygreek & Okra

• Rosemary

• Cloves

• Marigolds

• Star Anise

1. BV - used for cancer treatment

2. Fenugreek & Okra - used to remove microplastics

3. Rosemary - used to incrase the biocompatbility of other polymers

4. Cloves - anti-microbal propertites (can kill the spread of micro-organisms) and can numb gums

5. Marigold - can speed up wound healing

6. Star Anise - can be used for digestive help

What are some innovative drug delivery systems?

1. Nanoparticles (can be light/ultrasound activated) to allow direct target to the area

2. Implantable (can release drugs over time)

3. Personalized drug delivery using AI (like continuous glucose monitoring and insulin pumps)

4. Biomimetic (drug is disguised so body doesn’t attack it)

5. Stimuli responsive drug delivery (ph, temp and self regualted)

What are some important parameters of drug delivery

1. Mechanism of Delivery (is it oral or intravenous or transmucosal (eyes, nose, vaginal, etc.)

2. Bioavailability (how available is drug in that location)

   1. things that impact this is (environment and location (pH), drug solubility, method of drug delivery)

3. Material mechanical properties

4. Degradation

5. Drug Release / Dosing

6. Processing / manufacturing

Others include:

• Ease of use for patient

• Where in the body is the drug targetted?

• Cost

Stress vs Strain Curve time!

Strain terms (what is uniform vs total elongation)

Uniform elongation - deformation from the beginning of forming through necking

Total Elongation - deformation from the beginning through splitting

What is viscoelasticity?

the property of a material that exhibits both viscous (fluid-like flow and energy dissipation) and elastic (solid-like shape recovery and energy storage) characteristics when deformed

Demonstrated through

• creep (when a sample is put through constant stress to measure the strain as a function of time)

• stress relaxation

• oscillatory stress or dynamic experiments

What is creep, stress relaxation, and oscillatory stress

What are some polymer structures

1. Linear polymers

   1. made up of identical units (flexible & low melt temp)

2. Branched

   1. made up of main chain with side chains branched (more rigid + higher melt temp)

3. Cross-linked

   1. very rigid + highest melt temp (which u couldn’t ideally want since cells can’t grow in that)

Molecular weight (what are some of the principles)

The higher of MW the less mobility of chain → higher strength, greater thermal stability

can use MW to manipulate the application of material (ex: in manufacturing u can manipulate ur MW for diff strength props)

What is crystallinity

Alignment of polymer chains (the more ordered → crystalline; more amorphous → disordered)

it impacts the rigidity of material (the more crystallinity the more rigid)

Stress Strain Problem

How does Bulk vs Surface erosion occur? And what are the main chemical/biological pathways of drug breakdown?

With bulk erosion, it almost deteriorate from the insides releasing the drugs, whereas with surface the outer coating shrinks

The main pathways are

• Oxidative

• Hydrolytic

• Enzymatic

What are factors that affect drug release

1. Drug properties like MW, solubility

2. Geometry and design

3. Diffusion/Degradation

4. Polymer

5. Physiological Environment

Drug release Mathematical Models

1. Zero order release model

   1. Qt = Qi + kit