What is Bmax and Kd?

Bmax is the maximum specific binding in the same units as Y. It is the specific binding extrapolated to very high concentrations of radioligand, and so its value is almost always higher than any specific binding measured in your experiment. Kd is the equilibrium dissociation constant, in the same units as X.

How can you tell a KD and Bmax?


  1. = [receptor]× x × This equation is derived as follows: When you substitute [ligand] with x and [re-
  2. (8) Inserting and rearranging leads to.
  3. y = =
  4. y × (Kd + x) = Bmax × x. (12)
  5. You will get Kd and Bmax as results. Note that, when the concentration of the ligand (the.
  6. Kd + Kd. 2Kd.

What does saturable binding mean?

Saturable Binding The binding of a ligand to a single binding site is definable by the concentration of the binding site (Bmax) and the concentration of unbound ligand at which the binding site is 50% occupied (Kd). The Kd is also known as the equilibrium dissociation constant. Its reciprocal is a measure of affinity.

What is BMAX in pharmacology?

Bmax is the total density (concentration) of receptors in a sample of tissue. To refer to the concentration of available (free) receptors, terms Bavail or B’max can be used.

What are the units of BMAX?

Bmax is the total number of binding sites and is expressed in the same units as the y values (i.e., cpm, sites/cell, or fmol/mg protein). Kd is the equilibrium dissociation constant (expressed in the same units as [L], usually nM).

What does non specific binding mean?

Nonspecific binding is binding of the assay antibodies which is not correlated with the specificity of the antibodies. Also analytes can bind non-specifically. There are two kinds of nonspecific binding which normally occurs in the lab and which can not be distinguished from each other easily.

What is fractional occupancy?

Fractional occupancy is the fraction of all receptors that are bound to ligand. This equation is not useful, because you don’t know the concentration of unoccupied receptor, [Receptor].

What is a saturation binding curve?

Saturation binding curves are frequently plotted as a function of log10[L], often after normalization by division of the concentration of the receptor–ligand complex by the total estimated concentration of binding sites BMax to yield an occupancy value P.

Is binding of drug to plasma albumin is saturable?

In all subjects the binding of disopyramide to plasma proteins was saturable, but there were considerable differences in binding between subjects. The volume of distribution, total body clearance, and renal clearances of both total and unbound drug were calculated.

What are the units for BMAX?

How do you calculate kd from absorbance?


What is saturation binding in pharmacology?

What is saturation binding? In a saturation binding experiment, you vary the concentration of radioligand and measure binding at equilibrium. The goal is to determine the Kd (ligand concentration that binds to half the receptor sites at equilibrium) and Bmax (maximum number of binding sites).

What is the saturation curve for specific and total binding?

Fig D:Saturation curve for a ligand binding to a homogeneous receptor population. The total binding (T) includes a component of non-specific binding (NSB), which is non-saturable, and the remainder is specific binding (SB) which saturates at Bmax.

How do you determine the B Max of a drug?

In order to determine the characteristics of drug–receptor affinity and maximal binding capacity (B max ), broken cell preparations of a tissue are often incubated with a drug and allowed to come to equilibrium in vitro. A range of drug concentrations are incubated with a fixed amount of receptor and allowed to reach equilibrium.

Is it possible to observe Bmax experimentally?

Thus, one will never observe Bmax experimentally; Bmax may be approached but never attained. Half-maximal binding is obtained when L = KD (since Equation (4) becomes B = Bmax/2). In other words, the KD of a radioligand corresponds to its concentration for which half of the receptors are occupied.