Abstract
Poly[(N-isopropylacrylamide-co-acrylamide-co-(hydroxyethylmethacrylate))] [poly(NIPAAm-co-AAm-co-HEMA)] copolymer was synthesized as a new thermoresponsive material possessing a lower critical solution temperature (LCST) around 37 °C in phosphate buffer, pH 7.4, at a solution concentration of 1%, w/v. The influence of polymer concentration on LCST was determined by cloud point measurements and by microcalorimetric analysis. The copolymer was transformed in hydrogel microspheres by suspension reticulation of {single bond}OH groups with glutaraldehyde. The volume phase transition temperature (VPTT) of microspheres was determined by a new approach, which involves measurement of the increase in concentration of a blue dextran (BD) solution at different temperatures in the presence of dry microspheres. The minimum BD concentration that gives reliable and reproducible results was determined to be 1 mg/ml. However, the higher is the concentration of BD in solution the smaller is the error. Contrary to solution of the linear polymer which displays a sharp phase transition temperature, the dependence of water regain of the hydrogel with temperature lasts from 4 °C to 50 °C.
| Original language | English |
|---|---|
| Pages (from-to) | 3500-3509 |
| Number of pages | 10 |
| Journal | European Polymer Journal |
| Volume | 43 |
| Issue number | 8 |
| DOIs | |
| Publication status | Published - Aug 2007 |
Fingerprint
Keywords
- Blue dextran
- Equilibrium swelling ratio
- Lower critical solution temperature
- pH/Thermoresponsive copolymers
- Volume phase transition temperature
ASJC Scopus subject areas
- Organic Chemistry
- Polymers and Plastics
Cite this
Poly[(N-isopropylacrylamide-co-acrylamide-co-(hydroxyethylmethacrylate))] thermoresponsive microspheres : An accurate method based on solute exclusion technique to determine the volume phase transition temperature. / Fundueanu, G.; Constantin, M.; Bortolotti, F.; Cortesi, R.; Ascenzi, P.; Menegatti, E.
In: European Polymer Journal, Vol. 43, No. 8, 08.2007, p. 3500-3509.Research output: Contribution to journal › Article
}
TY - JOUR
T1 - Poly[(N-isopropylacrylamide-co-acrylamide-co-(hydroxyethylmethacrylate))] thermoresponsive microspheres
T2 - An accurate method based on solute exclusion technique to determine the volume phase transition temperature
AU - Fundueanu, G.
AU - Constantin, M.
AU - Bortolotti, F.
AU - Cortesi, R.
AU - Ascenzi, P.
AU - Menegatti, E.
PY - 2007/8
Y1 - 2007/8
N2 - Poly[(N-isopropylacrylamide-co-acrylamide-co-(hydroxyethylmethacrylate))] [poly(NIPAAm-co-AAm-co-HEMA)] copolymer was synthesized as a new thermoresponsive material possessing a lower critical solution temperature (LCST) around 37 °C in phosphate buffer, pH 7.4, at a solution concentration of 1%, w/v. The influence of polymer concentration on LCST was determined by cloud point measurements and by microcalorimetric analysis. The copolymer was transformed in hydrogel microspheres by suspension reticulation of {single bond}OH groups with glutaraldehyde. The volume phase transition temperature (VPTT) of microspheres was determined by a new approach, which involves measurement of the increase in concentration of a blue dextran (BD) solution at different temperatures in the presence of dry microspheres. The minimum BD concentration that gives reliable and reproducible results was determined to be 1 mg/ml. However, the higher is the concentration of BD in solution the smaller is the error. Contrary to solution of the linear polymer which displays a sharp phase transition temperature, the dependence of water regain of the hydrogel with temperature lasts from 4 °C to 50 °C.
AB - Poly[(N-isopropylacrylamide-co-acrylamide-co-(hydroxyethylmethacrylate))] [poly(NIPAAm-co-AAm-co-HEMA)] copolymer was synthesized as a new thermoresponsive material possessing a lower critical solution temperature (LCST) around 37 °C in phosphate buffer, pH 7.4, at a solution concentration of 1%, w/v. The influence of polymer concentration on LCST was determined by cloud point measurements and by microcalorimetric analysis. The copolymer was transformed in hydrogel microspheres by suspension reticulation of {single bond}OH groups with glutaraldehyde. The volume phase transition temperature (VPTT) of microspheres was determined by a new approach, which involves measurement of the increase in concentration of a blue dextran (BD) solution at different temperatures in the presence of dry microspheres. The minimum BD concentration that gives reliable and reproducible results was determined to be 1 mg/ml. However, the higher is the concentration of BD in solution the smaller is the error. Contrary to solution of the linear polymer which displays a sharp phase transition temperature, the dependence of water regain of the hydrogel with temperature lasts from 4 °C to 50 °C.
KW - Blue dextran
KW - Equilibrium swelling ratio
KW - Lower critical solution temperature
KW - pH/Thermoresponsive copolymers
KW - Volume phase transition temperature
UR - http://www.scopus.com/inward/record.url?scp=34547465722&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=34547465722&partnerID=8YFLogxK
U2 - 10.1016/j.eurpolymj.2007.05.026
DO - 10.1016/j.eurpolymj.2007.05.026
M3 - Article
AN - SCOPUS:34547465722
VL - 43
SP - 3500
EP - 3509
JO - European Polymer Journal
JF - European Polymer Journal
SN - 0014-3057
IS - 8
ER -