Meir Wilchek (Hebrew: מאיר אשר וילצ'ק; born 17 October 1935) is an Israeli biochemist.

Other contributions include conversion of serines to cysteines,[2] and was the first to prove experimentally the equation of Forster on dependence of energy transfer on distance,[3] an approach known today as FRET.

[5] Affinity chromatography[6] is a method of separating biochemical mixtures, based on a highly specific biologic interaction such as that between antigen and antibody, enzyme and substrate, or receptor and ligand.

[7] In 1972, Wilchek showed that the method can be used to remove toxic compounds from blood, as exemplified by the removal of heme peptides from blood using immobilized human serum albumin, thus laying the grounds for modern hemoperfusion[8] Affinity label is a molecule that is similar in structure to a particular substrate for a specific enzyme.

Affinity therapy, or immunotoxins is a biorecognition-based approach to selectively deliver a cytotoxic drug or toxin to a specific target cell.

In 2003, Wilchek collaborated in a team who introduced a system based on antibody-directed enzyme prodrug therapy (ADEPT), using antibody-conjugated alliinase to produce a cytotoxic agent, allicin, in situ (at the site) of the cancer[11] The avidin–biotin system is a technique for studying the interaction between two biomolecules in an indirect manner, as follows: Biotin is chemically coupled to a binder molecule (e.g., a protein, DNA, hormone, etc.)

The studies have culminated in the determination of the 3D structure of the avidin–biotin complex by X-ray crystallography,[13] which aids in the design of specific artificial recognition sites.