Method for the synthesis of a bifunctional complex

A method for obtaining a library of different bifunctional complexes each comprising a display molecule part and an identifier oligonucleotide part, said method comprising the steps of

• i) providing a nascent bifunctional complex comprising a chemical reaction site capable of receiving one or more reactants and a priming site capable of receiving one or more tags,
• ii) reacting the chemical reaction site with one or more reactants, and
• reacting the priming site with respective tag(s) identifying the reactant(s), wherein one or more enzymes catalyze the reaction;
• wherein steps (ii) and (iii) provide an intermediate bifunctional complex having a modified chemical reaction site containing a structural entity formed from the nascent bifunctional complex and the one or more reactants and a modified priming site containing the one or more tags;
• reacting the intermediate bifunctional complex with one or more additional reactants at the modified reactant site and one or more additional tags identifying the one or more additional reactants at the modified priming site using the methods of steps (ii) and (iii);
• optionally repeating step (iv) as many times as desired;
• and
• obtaining a library of different bifunctional complexes;
• vii) subjecting the library of different bifunctional complexes to a partitioning condition,
• viii) partitioning a display molecule, or a subset of display molecules, having a predetermined property from the remainder of the library,
• ix) selecting a display molecule, or a subset of display molecules, having said predetermined property,
• x) identifying display molecule(s) having said predetermined property by decoding the identifier oligonucleotide of the bifunctional complex, and
• xi) reacting the partitioned bifunctional complex(es) one or more times with further reactant(s) and reacting said bifunctional complexes with respective identifying tag(s), thereby generating a further library of different bifunctional complexes comprising a reaction product and an identifier oligonucleotide comprising tags identifying the reactants which have participated in the formation of the reaction product.