Analysis of interpenetrating polymer networks via quartz crystal microbalance with dissipation monitoring.
A quartz crystal microbalance with dissipation monitoring (QCM-D) was used to assess the physical properties of interpenetrating polymer networks (IPNs) through swelling experiments in ambient humidity and in phosphate-buffered saline (PBS), pH 7.4. The IPNs, based on acrylamide (AAm) and poly(ethylene glycol) (pEG), swell from thin, rigid films when dry (16.7 +/- 5.2 nm on Si/SiO(2)) to expanded, viscoelastic films when hydrated (107 +/- 24.2 nm on Si/SiO2). The dry IPNs could be analyzed using the Sauerbrey relationship, but for the hydrated films it was necessary to interpret QCM-D data with a Kelvin-Voigt viscoelastic model. A complex modulus |G| of 116 +/- 38.1 kPa for the swollen IPN surface on Si/SiO2 was defined by the model. The QCM-D was also employed to quantify the adsorption of human fibrinogen, a protein important in thrombus formation, onto the IPNs. Fibrinogen adsorption studies demonstrated the sensitivity of the QCM-D, as well as confirmed the nonfouling nature of the IPN surface, where less than 5 ng/cm2 of fibrinogen was adsorbed.
Irwin
E F
EF
Department of Bioengineering, University of California at Berkeley, Berkeley, California 94720, USA.
Ho
J E
JE
Kane
S R
SR
Healy
K E
KE
D000327:Adsorption; D002623:Chemistry Techniques, Analytical / Q000295:instrumentation*; D008832:Microchemistry / Q000295:instrumentation*; D011108:Polymers / Q000737:chemistry*; D011506:Proteins / Q000737:chemistry; D011791:Quartz; D013499:Surface Properties; D014867:Water / Q000737:chemistry; D014894:Weights and Measures
D011108:Polymers; D011506:Proteins; D014867:Water; D011791:Quartz