ISSN:
0959-8103
Keywords:
monolayer formation
;
PMMA-grafted chitin derivative
;
phase transition
;
accessible monolayer to lysozyme
;
Chemistry
;
Polymer and Materials Science
Source:
Wiley InterScience Backfile Collection 1832-2000
Topics:
Chemistry and Pharmacology
,
Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics
,
Physics
Notes:
The monolayer behaviour of poly(methyl methacrylate) (PMMA)-grafted chitin derivatives was studied on an air-water interface by measuring surface pressure-area isotherms. The formation of a stable monolayer indicates the well-defined packing and orientation of the chitin derivative, which can be regulated by the main-chain length under appropriate experimental conditions. The isotherms exhibit a transition point from a liquid expanded phase to a condensed phase at a surface pressure of approximately 15mN/m for almost all monolayers examined. The transition pressure decreases with increase of temperature from 10 to 20°C. The properties of the sub-phase affected the formation of a monolayer greatly. The collapse of a surface film takes place at lower pressure on the sub-phase of a 0.1 M NaCI solution. After introducing lysozyme at a concentration at 2.4 × 10-8M to the sub-phase, the monolayer showed an extensively expanded phase with a longer transition region. This indicates that the monolayer was degraded by the lysozyme, resulting in a disordered structure. The results are contrasted with those of an aqueous phase where N-acetylglucosamine residues may be inaccessible to lysozyme so that the degradation of the chitin derivative occurs at a very slow rate.
Additional Material:
5 Ill.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1002/pi.1994.210350401
