Supporting Information Materials and methods, scanning electron microscope image of Au nanoribbons after monolayer removal, energy-dispersive X-ray spectrum of an In 2 O 3-coated Au nanoribbon substrate, flow-cell measurement setup , extinction spectra of Au nanoribbons in buffer solutions with increasing glycerol concentrations (0-30 wt%), time-resolved peak shifts during the adsorption of DOPC lipid vesicles or BSA.