Polymer Nanocapsules. CE 435: Polymer Science & Engineering Emmanuel Lollis Andrew Hyun In Zachary Fine Jin woo Nam Shawreen Manish Shah. List of Contents. Objective Introduction Research Plan General Plan Potential Mechanisms to Trigger Drug Release
CE 435: Polymer Science & Engineering
Andrew Hyun In
State-of-the-art Nanocapsule Medications
Our end-goal is to overcome this limitation through the design and synthesis of a novel polymer nanocapsule with a target-specific release mechanism that can be changed on-demand.
Solid Colloidal particles size ranging 100-500nm
Characterized by a core-shell structure formed by self assembling of amphiphilic copolymers
Potential Mechanisms to Trigger Drug Release
Hydration & Diffusion
Use of Magnetic Fields
Coat nanocapsule with 1,1'-Dioctadecyl-3,3,3',3'-Tetramethylindodicarbocyanine-5,5' (DiD)
Use pulse of photon (~1 ms)
Negative effect: uncaging process during photolysis creates radicals (harmful to cells)
Scavengers are added to remove radicals
External radio frequency stimulus
Coat with silica
Possible to control release
Efficiency is high
Synthesis of Polymer Nanocapsule
Anionic polymerization in mini emulsion
Processing of preformed polymers
Has been successful tested as a carrier for other drugs like thymopentin
Easy to synthesize
Sensitive to certain disturbances, to make a timely drug release
When compared on ‘entrapment efficiency’ with other polymeric materials.
It is synthesized from butyl cyanoacetate
It is used as an adhesive in various applications
Suitable inhibitor are added to prevent It from polymerization.
Method to be employed is miniemulsion polymerization.
Mechanism followed is of anionic polymerization
Allows fine tuning of properties of nanocapsules.
Low energy requiring project; no high stirring, high pressure etc.
This is obtained by either varying the temperature, which is called phase inversion temperature method or the composition, which is called the phase inversion composition method, while keeping the other parameter constant.
The latter one is used here.
Inhibitor like Methanesulfonic acid is added for carrying out uninterrupted emulsification.
Organic and Aqueous phases are reacted by slow addition of aqueous phase.
The drug is loaded in the polymer during the reaction.
Ultracentrifugation is carried out
Nanoparticles thus formed are suspended in a solution for dispersion.
Size of nanoparticles depends upon concentration of surfactants and stabilizers. It is expected to be around 20-100nm.
Also known as solvent displacement or interfacial deposition method.
Process contains two phases : Solvent (organic) phase and non-solvent (aqueous) phase.
Polymer is in the solvent phase.
Suitable stabilizer is used e.g. Polysorbate.
Drug is added during the addition.
Process takes place in acidic environment. The system is neutralized after the process.
Nanoparticle formation consists of three stages : Nucleation, growth and aggregation.
Attaining super saturation is the driving force for the system.
Particle size and distribution is the most important factor in determining the success of the process.
It establishes several important factors like biocompatibility and target drug delivering capacity.
The time of release is also a function of the particle size.
Surface area is another important factor.
Verification of Success
Test 1 – Determine whether or not the nanocapsule can retain its contents over time
Test 2 – Determine whether or not the nanocapsule can release its contents when triggered
Test 3 – Determine whether or not the nanocapsule can resist shear forces
Test 1 – Determine whether or not the nanocapsules are toxic to cells
Test 2 – Conduct a live test on cells
Novel therapeutic systems : hormones, vitamins, antifungals, etc.
Encapsulation : polymers, enzymes, biological cells
Market exceed $30 billion by 2015
Enhance cure rate of cancer
Combining Two Methods : IR light & DiD(enzyme)
2. Affect without disturbing neighbor tissues