Synthesis and characterization of putrescine-based poly(phosphoester-urethanes)

$61.74 plus tax (Refund Policy)

Buy Article:

Abstract:

A novel set of putrescine-based segmented polyurethanes was synthesized using 1,4-butane-diisocyante and phosphoester diols, and was characterized for its potential as a degradable biomaterial. These poly(phosphoester-urethanes) (PPU) were flexible polymers with ultimate tensile strength (UTS) from 2 to 3 MPa, elongations up to 80% and tan δ near 0.15. The incorporation of phosphoester bonds in the backbone of the polymer by using bis(2-hydroxyethyl)phosphite (BGP) and bis(6-hydroxyhexyl)-phosphite (BHP) as chain extenders resulted in hydrolytic degradation which was evaluated in vitro. By varying the content of the phosphoester diol BGP, degradation rate, as followed by mass loss and GPC, could be modulated. Polymers based on the more hydrophobic monomer, BHP, showed slower degradation than corresponding BGP based polymers. Tensile properties of PPU-B2 after 22 days in vitro degradation show more than a 50% drop in UTS and ultimate elongation, likely caused by void spaces left behind in the polymer after mass loss and swelling. The attachment of a drug, PAS, pendant to the phosphoester group of the PPU was demonstrated. PAS was linked via the spacer 4-hydroxybenzaldehyde, and free, intact drug was released in about 5 h from a thin film.

Keywords: Degradable polymers; drug delivery; poly(phosphoesters); polyurethanes

Document Type: Research Article

DOI: http://dx.doi.org/10.1163/156856293X00186

Affiliations: Department of Biomedical Engineering, Johns Hopkins University, Charles and 34th Sts., Baltimore, MD 21218, USA

Publication date: January 1, 1993

Related content

Share Content

Access Key

Free Content
Free content
New Content
New content
Open Access Content
Open access content
Subscribed Content
Subscribed content
Free Trial Content
Free trial content
Cookie Policy
X
Cookie Policy
ingentaconnect website makes use of cookies so as to keep track of data that you have filled in. I am Happy with this Find out more