Ligand binding competitive

The basic clinical tool used at the present time Is the competitive ligand binding assay for 25-OH-D. Although concentrations are low In the serum of patients with osteomalacia and v . tamln D deficiency rickets, we have recently noted the Interesting paradox that levels can be only 1/2 normal In the face of oyert bone disease (32). This had led us to propose that substrate levels of 25-OH-D3 available to the hydroxylase In kidney which Is responsible for the conversion of 25-OH-D3 to the tissue active metabolite, l,25(OH)2D3, may be rate limiting for this enzyme. 

Fig. 5.10 Principle of competitive ligand binding MS assays. Protein (P) molecules react with the test ligand (L) to form a protein-ligand complex (PL). The extent of complex forming is monitored by the addition of a bioactive reporter ligand (R) resulting in the formation of protein-reporter complex (PR). The concentration free R is directly dependent on the concentration and affinity of L R is monitored by ESI-MS at its corresponding m/z trace.

Sigurskjold, B.W. (2000) Exact analysis of competition ligand binding by displacement isothermal titration calorimetry, Anal.Biochem. 277, 260-266 ... 

Application of molecularly imprinted polymers in competitive ligand binding assays for analysis of biological samples... 

SUMMARY OF STUDIES ON COMPETITIVE LIGAND BINDING EXPERIMENTS EMPLOYING MIPS... 

Andersson, L.I. Application of molecularly imprinted polymers in competitive ligand binding assays for analysis of biological samples. In Molecularly Imprinted Polymers Man-made Mimics of Antibodies and Their Applications in Analytical Chemistry, Sellergren, B., Ed. Elsevier Amsterdam, 2001 341-354. 

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