TY - JOUR
T1 - Highly efficient immobilisation of antibody fragments to functionalised lipid monolayers
AU - Vikholm, Inger
AU - Viitala, Tapani
AU - Albers, Willem M.
AU - Peltonen, Jouko
N1 - Funding Information:
This work was financed by the Technology Development Centre of Finland, the Academy of Finland and the Technical Research Centre of Finland.
PY - 1999/9/21
Y1 - 1999/9/21
N2 - The covalent attachment of Fab' fragments of polyclonal anti-human IgG to a lipid with a terminal linker group was examined by means of quartz crystal microbalance and surface plasmon resonance measurements. The linker lipid was embedded in binary or ternary monolayers of dipalmitoylphosphatidylcholine (DPPC) and cholesterol. Atomic force microscopy images of the films deposited on silanised SiO2 substrates showed that Fab' fragments take a standing position, thus giving site-directed immobilisation. Human IgG forms a network on interaction with the antibodies. Non-specific binding of bovine serum albumin was found to be very low when DPPC was used as the host matrix. At an optimal Fab' fragment concentration a binding capacity above 60% was obtained. However, if the surface concentration of the immobilised antibodies was too high, the binding capacity decreased due to steric hindrance. The results demonstrate that the covalent coupling of Fab' fragments to N-(ε-maleimidocaproyl)-dipalmitoylphosphatidylethanolamine (DPPE-EMC) embedded in a host monolayer matrix of DPPC is a promising approach to achieve a site-directed immobilisation of antibodies with high antigen-binding efficiency. Copyright (C) 1999 Elsevier Science B.V.
AB - The covalent attachment of Fab' fragments of polyclonal anti-human IgG to a lipid with a terminal linker group was examined by means of quartz crystal microbalance and surface plasmon resonance measurements. The linker lipid was embedded in binary or ternary monolayers of dipalmitoylphosphatidylcholine (DPPC) and cholesterol. Atomic force microscopy images of the films deposited on silanised SiO2 substrates showed that Fab' fragments take a standing position, thus giving site-directed immobilisation. Human IgG forms a network on interaction with the antibodies. Non-specific binding of bovine serum albumin was found to be very low when DPPC was used as the host matrix. At an optimal Fab' fragment concentration a binding capacity above 60% was obtained. However, if the surface concentration of the immobilised antibodies was too high, the binding capacity decreased due to steric hindrance. The results demonstrate that the covalent coupling of Fab' fragments to N-(ε-maleimidocaproyl)-dipalmitoylphosphatidylethanolamine (DPPE-EMC) embedded in a host monolayer matrix of DPPC is a promising approach to achieve a site-directed immobilisation of antibodies with high antigen-binding efficiency. Copyright (C) 1999 Elsevier Science B.V.
KW - Antibody fragment
KW - Antigen binding
KW - Atomic force microscopy
KW - Phospholipid monolayer
KW - Quartz crystal microbalance
KW - Surface plasmon resonance
UR - http://www.scopus.com/inward/record.url?scp=0032825249&partnerID=8YFLogxK
U2 - 10.1016/S0005-2736(99)00112-1
DO - 10.1016/S0005-2736(99)00112-1
M3 - Article
C2 - 10561470
AN - SCOPUS:0032825249
SN - 0005-2736
VL - 1421
SP - 39
EP - 52
JO - Biochimica et Biophysica Acta - Biomembranes
JF - Biochimica et Biophysica Acta - Biomembranes
IS - 1
ER -