PMID- 18783258
OWN - NLM
STAT- MEDLINE
DCOM- 20081113
LR  - 20081015
IS  - 0743-7463 (Print)
IS  - 0743-7463 (Linking)
VI  - 24
IP  - 20
DP  - 2008 Oct 21
TI  - Effect of lysozyme adsorption on the interfacial rheology of DPPC and cholesteryl 
      myristate films.
PG  - 11728-33
LID - 10.1021/la8016485 [doi]
AB  - A model tear film lipid layer composed of a binary mixture of cholesteryl 
      myristate (CM) and 1,2-dipalmitoyl- sn-glycero-3-phosphocholine (DPPC) was 
      characterized using surface tension measurements, Brewster angle microscopy (BAM) 
      and interfacial stress rheology (ISR). Isotherms showed that films containing 
      >or=90 mol % CM have a 17-fold greater % area loss between the first and second 
      compressions than the films with less CM. BAM images clearly showed that CM films 
      did not expand after compression, and solid-like regions extending 1-2 mm were 
      observed at low pressures (1 mN/m). Lipid films with <or=70 mol % CM expanded 
      after compression in BAM indicating that the films were primarily fluid. ISR data 
      confirmed these results, as DPPC and 30:70 CM/DPPC films were fluid at all 
      pressures and more compliant than films with higher CM content. Films with >or=50 
      mol % CM became elastic at higher surface pressures. Increasing CM content 
      reduced the surface pressure at which the mixed film became elastic. Lysozyme 
      adsorption into a CM film increased the compressibility and resulted in a more 
      expanded film. Lysozyme increased the ductility of the CM/DPPC films with no film 
      breakdown occurring up to the highest pressure measured (40 mN/m). In summary, CM 
      increased the elasticity of the lipid films, but also caused them to become 
      brittle and incapable of expansion following compression. Lysozyme adsorption 
      increased the ductility and decreased the isotherm hysteresis for CM/DPPC films.
FAU - Nishimura, Stefanie Y
AU  - Nishimura SY
AD  - Department of Chemical Engineering, Stanford University, USA.
FAU - Magana, Giovanni Mata
AU  - Magana GM
FAU - Ketelson, Howard A
AU  - Ketelson HA
FAU - Fuller, Gerald G
AU  - Fuller GG
LA  - eng
PT  - Journal Article
PT  - Research Support, Non-U.S. Gov't
DEP - 20080911
PL  - United States
TA  - Langmuir
JT  - Langmuir : the ACS journal of surfaces and colloids
JID - 9882736
RN  - 0 (Cholesterol Esters)
RN  - 0 (Lipids)
RN  - 1989-52-2 (cholesteryl myristate)
RN  - 2644-64-6 (1,2-Dipalmitoylphosphatidylcholine)
RN  - EC 3.2.1.- (hen egg lysozyme)
RN  - EC 3.2.1.17 (Muramidase)
SB  - IM
MH  - 1,2-Dipalmitoylphosphatidylcholine/*chemistry
MH  - Adsorption
MH  - Animals
MH  - Chickens
MH  - Cholesterol Esters/*chemistry
MH  - Hydrogen-Ion Concentration
MH  - Lipids/chemistry
MH  - Microscopy
MH  - Muramidase/*chemistry
MH  - Pressure
MH  - Rheology/*methods
MH  - Stress, Mechanical
MH  - Surface Properties
MH  - Surface Tension
EDAT- 2008/09/12 09:00
MHDA- 2008/11/14 09:00
CRDT- 2008/09/12 09:00
PHST- 2008/09/12 09:00 [pubmed]
PHST- 2008/11/14 09:00 [medline]
PHST- 2008/09/12 09:00 [entrez]
AID - 10.1021/la8016485 [doi]
PST - ppublish
SO  - Langmuir. 2008 Oct 21;24(20):11728-33. doi: 10.1021/la8016485. Epub 2008 Sep 11.