Abstract: The present disclosure discloses a process for immobilizing polypeptides on a surface, said method comprising: (a) coating a surface with a molecule to capture biotin tagged polypeptide to obtain a coated surface; and (b) contacting at least two biotin tagged polypeptides with the coated surface of step (a) to obtain immobilized polypeptides, wherein the biotin tagged polypeptide comprises a biotin linked to a recombinant polypeptide. The present disclosure further discloses an in-vitro method for detecting at least one binder molecule in a sample, and a process for obtaining biotin tagged polypeptide.