Tunable surface free energies of functionalized molecular layers on Si surfaces for microfluidic immunosensor applications

► Surface free energies of different antibody layers evaluated. ► Each antibody linked via different aminosilanes on non- and nano-textured surfaces. ► Type of terminal groups, molecular orientations affected the surface free energies. ► Surface free energies: anti-BSA < anti-PSA < anti-CRP with APTES. ► Tunability of surface free energies achieved up to 9.6 mJ/m2.