1 / 8

Introduction/Materials & Methods (Kinetic Studies)

Introduction/Materials & Methods (Kinetic Studies). By: Kristin Ackermann Amanda Rohs Blanca Skelding. Introduction. Biocompatible polymers permit the controlled release of macromolecules EVAc Polymer systems have a wide variety of applications

jovanna
Download Presentation

Introduction/Materials & Methods (Kinetic Studies)

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Introduction/Materials & Methods (Kinetic Studies) By: Kristin Ackermann Amanda Rohs Blanca Skelding

  2. Introduction • Biocompatible polymers permit the controlled release of macromolecules • EVAc Polymer systems have a wide variety of applications • Chemotactic and growth factor release systems • Informational macromolecules • Delivery systems for insulin, interferon and antigens

  3. Introduction • Mechanism for macromolecular release has not been explained • Polymers capable of releasing molecules larger than their permeability limit • Incorporating macromolecules into a non-porous matrix results in the formation of an interconnected pore network • Diffusion of molecules through network provides basis for controlled release

  4. Method • BSA, β-lactoglobulin A and lysozyme powders sieved into specific size ranges • Dispersed in a 10% ethylene-vinyl acetate solution • Suspensions cast in flat glass mold at -80 C • Sheets dried in two 48-hour stages (-20 C and under vaccum at 20 C)

  5. Method • To test kinetics, 9 slabs were prepared: • Dimensions: 1cm x 1cm x 1mm • Coated on 5 faces using paraffin • One 1cm x 1cm face exposed (allowing for diffusion on only one face) • Stainless steel autoclips were pressed into the paraffin for anchors when placed in release medium

  6. Method • Release medium • Composed of 0.9% NaCl solution • Placed in 10mL amounts in 20mL vials • Slabs removed at specified time points • Slabs placed in vials containing fresh saline • Old solutions were spectrophotometrically analyzed for protein content

  7. Method • Protein particle densities determined using pycnometer with methylene chloride as solvent • Porosity was determined before and after release. • Before: dividing protein concentration in slab by protein particle density • After: liquid leaching of salicylate

  8. Method • In general, porosity values before and after release agreed to within 5% • Thickness of polymer slabs was also measured using a micrometer • Standard deviation for thickness measurements was less than 4% for each slab

More Related