fulltext.study @t Gmail

Structural characterization of phosphorylated chitosan and their applications as effective additives of calcium phosphate cements

Paper ID Volume ID Publish Year Pages File Format Full-Text
13836 915 2001 9 PDF Available
Title
Structural characterization of phosphorylated chitosan and their applications as effective additives of calcium phosphate cements
Abstract

Chitosan was phosphorylated by P2O5 in methanesulfonic acid and the product as water-soluble phosphorylated chitosan (P-chitosans) was then characterized by phosphorus elemental analysis, IR and 31P-NMR spectroscopy. Two calcium phosphate cement (CPC) systems, i.e. (1) monocalcium phosphate monohydrate (MCPM) and calcium oxide (CaO) in 1 mphosphate buffer (pH=7.4) and (2) dicalcium phosphate dihydrate (DCPD) and calcium hydroxide [Ca(OH)2] in 1 m Na2HPO4 solution, were chosen to improve their mechanical properties by the addition of water-soluble P-chitosans with various values for molecular weight, degree of deacetylation (DD) and degree of substitution (DS). The results show that the compressive strength (CS) and Young's modulus of both CPC formulations after setting were obviously increased and setting time was slightly prolonged by adding water-soluble P-chitosan to the liquid phases. When a suitable amount of P-chitosan was used, two improved CPC formulations were obtained with much better mechanical properties while the setting times were not longer than 15 min. The enhancement of compressive strength was due to high Ca2+-binding ability of phosphorylated chitosan, which could tightly bind the newly formed hydroxyapatite (HA) particles together by polymeric chains. It was noted that excessive addition of P-chitosan would lead to slow setting or no setting at all. The hardened CPC samples containing P-chitosan were characterized via X-ray diffraction spectra and scanning electron microscopy. Their leaching experiment was also carried out. The results indicated that P-chitosan-forced calcium phosphate cements have some good characteristics for clinical applications.

Keywords
Phosphorylated chitosan; Calcium phosphate cements; Mechanical property
First Page Preview
Structural characterization of phosphorylated chitosan and their applications as effective additives of calcium phosphate cements
Get Full-Text Now
Don't Miss Today's Special Offer
Price was $35.95
You save - $31
Price after discount Only $4.95
100% Money Back Guarantee
Full-text PDF Download
Online Support
Any Questions? feel free to contact us
Publisher
Database: Elsevier - ScienceDirect
Journal: Biomaterials - Volume 22, Issue 16, 15 August 2001, Pages 2247–2255
Authors
, , , ,
Subjects
Physical Sciences and Engineering Chemical Engineering Bioengineering
Get Full-Text Now
Don't Miss Today's Special Offer
Price was $35.95
You save - $31
Price after discount Only $4.95
100% Money Back Guarantee
Full-text PDF Download
Online Support
Any Questions? feel free to contact us