Biomedical Engineering Reference
In-Depth Information
Fig. 4.1
CD spectra
showing the conformational
analysis of peptides binding
on single-wall carbon
nanotube (SWCN). (
a
) and
(
b
) represents two different
peptides UW-1 and B3,
respectively. In (
a
),
curves 1
and
2
represent UW-1 with
SWNT at pH 7.5 and
concentrations of 6
μ
M and
12
M, respectively.
Curve 3
shows the free UW peptide
and
curve 4
shows the CD at
pH 3.0 (Adapted from [
11
])
μ
pH and due to adsorption on carbon nanotube changes to beta-turn (beta-hairpin). In
the case of B3, binding to carbon nanotube does not change its helical conformation
at neutral pH.
4.3
Isothermal Titration Calorimetry
Isothermal Titration Calorimetry (ITC) is a quantitative technique which can
determine thermodynamic parameters in solution such as binding affinity, binding
stoichiometry, and binding enthalpy change. Upon titration of protein to the NP
solution, the changes in temperature are measured. The heat changes are fitted to
isothermal functions.
