Binding constant

Binding constant

The binding constant is a special case of the equilibrium constant K. The equilibrium state of molecular binding, i.e. the balance between the binding and dissociation processes after infinite reaction time, may be formalized as the unbound compounds (reactants, A and B) transforming into a complex (product, C):

:A + B ightleftharpoons C

This directionality of reaction defines the association equilibrium constant Ka:

:K_{ass} = {k_{on} over k_{off = { [C] over [A] imes [B] } (second order or bimolecular association)

Since the binding constant is related to the molar free enthalpy, it is used to quantify the affinity of binding. For this purpose, the reverse directionality is used because the resulting formalism is a reaction of first order and thus its dimension is always in mol (or mol/L). This defines the dissociation equilibrium constant Kdiss:

:K_{diss} = {k_{off} over k_{on = { [A] imes [B] over [C] } (first order dissociation)

Wikimedia Foundation. 2010.

Игры ⚽ Нужно сделать НИР?

Look at other dictionaries:

  • binding constant — association c …   Medical dictionary

  • Binding coefficient — In medicinal chemistry and pharmacology, a binding coefficient is a quantity representing the extent to which a chemical compound will bind to a macromolecule. [Schurr JM, Rangel DP, Aragon SR. (2005)… …   Wikipedia

  • Binding energy — Nuclear physics Radioactive decay Nuclear fission Nuclear fusion Classical decays …   Wikipedia

  • constant — A quantity that, under stated conditions, does not vary with changes in the environment. association c. 1. in experimental immunology, a mathematical expression of hapten antibody interaction : average association c., K = [hapten bound… …   Medical dictionary

  • Dissociation constant — Kd redirects here. For other uses, see KD (disambiguation). In chemistry, biochemistry, and pharmacology, a dissociation constant is a specific type of equilibrium constant that measures the propensity of a larger object to separate (dissociate)… …   Wikipedia

  • Filter binding assay — In biochemistry, one of the ways to learn about an interaction between two molecules is to determine the binding constant, which is a number that describes the ratio of unbound and bound molecules. This information reveals the affinity between… …   Wikipedia

  • Acid dissociation constant — Acetic acid, a weak acid, donates a proton (hydrogen ion, high …   Wikipedia

  • Nuclear binding energy — is the energy required to split a nucleus of an atom into its component parts. The component parts are neutrons and protons, which are collectively called nucleons. If the binding energy for the products is higher when light nuclei fuse, or when… …   Wikipedia

  • Equilibrium constant — For a general chemical reaction:alpha A +eta B ... ightleftharpoons sigma S+ au T ...the equilibrium constant can be defined by [F.J,C. Rossotti and H. Rossotti, The Determination of Stability Constants, McGraw Hill, 1961.] :K=frac{S ^sigma {{T^ …   Wikipedia

  • Law binding — Law Law (l[add]), n. [OE. lawe, laghe, AS. lagu, from the root of E. lie: akin to OS. lag, Icel. l[ o]g, Sw. lag, Dan. lov; cf. L. lex, E. legal. A law is that which is laid, set, or fixed; like statute, fr. L. statuere to make to stand. See… …   The Collaborative International Dictionary of English

Share the article and excerpts

Direct link
Do a right-click on the link above
and select “Copy Link”