A regioregular polyalkylthiophene bearing covalently-linked biotin, and its interaction with avidin in solution and in thin films.

A regioregular copolymer of 3-hexylthiophene and 3-(6-hydroxyhex-1-yl)thiophene has been functionalised with biotin hydrazide; binding of avidin to the biotin moieties causes drastic changes to the absorption spectrum of the polymer in solution, and to the electrochemistry and conductivity of the polymer in thin films.