TY - JOUR
T1 - Protein adsorption on nano-patterned hydrogenated amorphous carbon model surfaces
AU - Mughal, MZ
AU - Lemoine, P
AU - Lubarsky, G
AU - Maguire, PD
PY - 2016/5/5
Y1 - 2016/5/5
N2 - Predicting how proteins fold and adsorb onto surfaces is a complex problem of strong relevance to the health and environmental sectors. In this work, two nano-patterning techniques, namely focused ion beam (FIB) milling and atomic force microscopy (AFM) nanoindentation were used to develop hydrogenated amorphous carbon (a-C:H) model surfaces with similar nano-topography but different local composition. On the un-patterned surfaces, bovine plasma fibrinogen (BPF) resulted in a thicker and rougher adsorbed film than bovine serum albumin (BSA), although FTIR analysis indicated that, the secondary structure of the proteins changed similarly, with an increase of the -sheet component (+27% and +34% for BSA and BPF, respectively). AFM analysis on the FIB-patterned surfaces indicates that patterning can modify specific protein adsorption behaviors. Moreover, the patterns were compared by imaging the AFM tip/surface adhesive force for BSA adsorbed on either AFM tips or patterned surfaces. The results shows an electrostatic interaction between the implanted Ga+ and BSA surface, modifying the adsorption behavior and the adhesive force. Modelling this interaction gave an estimate of the surface charge per protein, a significantly lower value than in dilute solution (-1.8e instead of -18e). This finding is indicative of protein misfolding, as detected in the FTIR analysis.
AB - Predicting how proteins fold and adsorb onto surfaces is a complex problem of strong relevance to the health and environmental sectors. In this work, two nano-patterning techniques, namely focused ion beam (FIB) milling and atomic force microscopy (AFM) nanoindentation were used to develop hydrogenated amorphous carbon (a-C:H) model surfaces with similar nano-topography but different local composition. On the un-patterned surfaces, bovine plasma fibrinogen (BPF) resulted in a thicker and rougher adsorbed film than bovine serum albumin (BSA), although FTIR analysis indicated that, the secondary structure of the proteins changed similarly, with an increase of the -sheet component (+27% and +34% for BSA and BPF, respectively). AFM analysis on the FIB-patterned surfaces indicates that patterning can modify specific protein adsorption behaviors. Moreover, the patterns were compared by imaging the AFM tip/surface adhesive force for BSA adsorbed on either AFM tips or patterned surfaces. The results shows an electrostatic interaction between the implanted Ga+ and BSA surface, modifying the adsorption behavior and the adhesive force. Modelling this interaction gave an estimate of the surface charge per protein, a significantly lower value than in dilute solution (-1.8e instead of -18e). This finding is indicative of protein misfolding, as detected in the FTIR analysis.
KW - Focused ion beam (FIB)
KW - Atomic force microscopy (AFM) nanoindentation
KW - Nano-patterning
KW - Hydrogenated amorphous carbon
KW - Protein adsorption
UR - http://www.sciencedirect.com/science/article/pii/S0264127516301897
UR - https://pure.ulster.ac.uk/en/publications/protein-adsorption-on-nano-patterned-hydrogenated-amorphous-carbo-3
U2 - 10.1016/j.matdes.2016.02.043
DO - 10.1016/j.matdes.2016.02.043
M3 - Article
VL - 97
SP - 239
EP - 248
JO - Materials and Design
JF - Materials and Design
SN - 0261-3069
ER -