Modifying inorganic surfaces with covalently attached organic molecules can be useful to fabricate biomimetic lipid membrane coatings on otherwise intractable surfaces for various applications such as medical implants and biosensors. A classic example is the formation of a hydrophobic, self-assembled monolayer, and a full-spanning monolayer of organic molecules has long been considered a design prerequisite to drive subsequent lipid self-assembly processes in such cases. Expanding on this viewpoint, herein, we demonstrate that functionalizing a titanium oxide (TiO2) surface with a low surface coverage of hydroxyl-terminated, 11-hydroxyundecylphosphonic acid (HUPA) in the sub-monolayer regime can readily transform the TiO2 surface in an “on/off” manner from fully repelling zwitterionic lipid bicelle adsorption to supporting formation of a well-packed bicelle adlayer coating that is useful for biosensing applications. Using the quartz crystal microbalance-dissipation (QCM-D) technique, we characterized HUPA deposition in various solvent systems and identified optimal room-temperature, solution-phase deposition conditions while further developing bicelle coating protocols and surface passivation strategies to facilitate selective detection of membrane-protein and antibody-antigen interactions. Strikingly, when chemisorbed HUPA covered <20% of the TiO2 surface, there was a >25-fold increase in bicelle adsorption compared to the bare TiO2 case. To rationalize these findings, we discuss mechanistic aspects related to how HUPA attachment dampens steric-hydration forces on the TiO2 surface and our low-coverage surface functionalization approach in the sub-monolayer regime demonstrates a broadly applicable interfacial science strategy to modulate biomacromolecular adsorption processes and can be useful for bicelle-based, membrane-on-a-chip applications.