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3.2.2.
Introductory example:
ITC
(Isothermal
titration
calorimetry)
ITC is a modern type of analysis based on thermodynamic principles. It is
much used in biosciences. Here is an example using ITC to study the binding
of a ligand to a protein:
The ITC instrument records the heat absorbed (endothermic) or produced
(exothermic) when a reaction occurs. In this case a small molecule (tri-NAG)
is added stepwise in small portions to lysozyme (which binds tri-NAG). The
reaction is fortunately fast, and provides a heat peak. Once equilibrium is
obtained (no more heat produced/absorbed) another injection is performed.
The experiment continues until no heat is produced upon injection of more
ligand.