In each case, the protein solution (1 mg/mL) was added after 15 min of incubation and continuous acquisition of interfacial rheology data for the naked liquid-liquid interface. Before and after each time sweep, a frequency sweep (with displacements of 1.0 10 -3 rad) and amplitude sweeps (at a frequency of 0.1 Hz) were carried out to examine the frequency-dependent behaviour of corresponding interfaces and to ensure that the selected displacement and frequency selected were within the linear viscoelastic region. For the sequential adsorption experiment, one hour after the formation of the protein layer, replacement of the aqueous phase with PBS (no protein) was achieved using a high resolution flow control system (Elveflow, 30 min, 1 mL/min; without disrupting the formed nanosheet) in the rheology trough. This washing step ensures that nonadsorbed protein molecules are removed from the aqueous phase. Subsequent injection of a second protein solutions (final concentration of 1 mg/mL) or treatment with sulfo-SMCC (at a concentration of 2 mg/mL) was then monitored for 1 h, followed by 30 min of further washing with PBS and characterisation via frequency sweep (at an oscillatory displacement of 1.0 10 -3 rad), stress relaxation experiment (0.5 % strain) and amplitude sweep (at a frequency of 0.1 Hz).