90 likes | 216 Views
Poly ( β -amino ester) A6. Chain arrangements and Interactions. 14 C : 5 O : 1 N, acrylate terminated alternating macromer H-bonding potential in oxygen groups Hydrophobic interactions from isobutyl group Steric hindrance / entanglement. 1.2:1 ratio of diacrylate:amine.
E N D
Chain arrangements and Interactions • 14 C : 5 O : 1 N, acrylate terminated alternating macromer • H-bonding potential in oxygen groups • Hydrophobic interactions from isobutyl group • Steric hindrance / entanglement 1.2:1 ratio of diacrylate:amine
Structure / Morphology • Linear macromer • Susceptible to polar, H-bonding, organic solvents • Chemically or UV crosslinked to form hydrogel • Free radical polymerization reaction • This specific polymer is densely crosslinked • Forms a flexible solid
Physical Properties of A6 • Modulus of 25 Mpa, which is similar to the moduli for elastomers and non-biodegradable polyurethanes. • Total degradation time was greater than three months • Generally hydrophobic gel and exhibits low swelling in aqueous conditions. Figure 1: Degradation time for four separate poly(β-amino ester). The percent mass loss was measured over the course of 100 days.
Additives • PEGylation • Increase hydrophilicity • ‘Stealth’ drug carrier • Iron oxide nanoparticles • Remote degradation • Drugs! • Hydrophobic drugs = slow, degradation and diffusion-based release • Hydrophilic drugs = rapid, diffusive release • Porogen
Source comparison • Internet – Great for journal articles. Difficult to find monomer properties and reaction information • SciFinder Scholar – monomer properties, journal articles. Do not have to sift through “bad” references. • Polymer Handbook (4th Ed): index of monomer properties, including CAS registry #. Slower to use then SciFinder or internet, but more convenient once you have the actual book
Works Cited • Hawkins, A.M., et al. “Synthesis and analysis of degradation, mechanical and toxicity properties of poly(Beta-amino ester) degradable hydrogels.” Act Bio 7-5, 2011 (1956- 1964) • Anderson, D.G., et al. “A combinatorial library of photocrosslinkable and degradable materials.” Adv Mat 18, 2006 (2614-2618) • Brandrup, J.; Immergut, Edmund H.; Grulke, Eric A.; Abe, Akihiro; Bloch, Daniel R. (1999; 2005). Polymer Handbook (4th Edition).. John Wiley & Sons. • Necas, J, L Bartosikova, P Brauner, and J Kolar. "Hyaluronic acid (hyaluronan): a review." • VeterinarniMedicina. 53. (2008): 397-411. Print. <http://www.vri.cz/docs/vetmed/53-8-397.pdf>. • "Material Safety Data Sheet." Amresco. N.p., 10-May-2011. Web. 21 Sep 2011. <http://www.amresco- inc.com/media.acux?path=/media/products/msds/MSDS-J548.pdf>. • "POLOXAMINE 1307." EWG's Skin Deep. Environmental Working Group, 2011. Web. 21 Sep 2011. <http://www.ewg.org/skindeep/ingredient.php?ingred06=722350>. • "Edetate Disodium (Systemic)." Drugs.com. N.p., 02-09-2000. Web. 21 Sep 2011. <http://www.drugs.com/mmx/edetate- disodium.html>.