Supporting Information pH-dependence of single-protein adsorption and diffusion at a liquid chromatographic interface Lydia Kisley,1 Mohan-Vivekanandan Poongavanam2, Katerina Kourentzi,3 Richard C. Willson,2,3,4,5 Christy F. Landes 1,6 * 1 Department of Chemistry, Rice University, Houston, TX 77251; 2 Department of Biology & Biochemistry, University of Houston, Houston, TX 77004; 3 Department of Chemical & Biomolecular Engineering, University of Houston, Houston, TX 77004; 4 Houston Methodist Research Institute, Houston, TX, 77030; 5 Centro de Biotecnología FEMSA, Departamento de Biotecnología e Ingeniería de Alimentos, Tecnológico de Monterrey, Monterrey, NL 64849, Mexico; 6 Department of Electrical and Computer Engineering, Rice University, Houston, TX 77251 Corresponding Author * Dr. Christy F. Landes; Rice University; Department of Chemistry; P.O. Box 1892, MS 60; Houston, TX 77251; (713) 348-4232; [email protected] Figure S1. Photobleaching occurs during high affinity adsorption of alpha-lactalbumin at low pH. The summed intensity across the TIRF image over time exhibits a single exponential decay. The rate of decay (0.0023 ± 0.0002 frames-1) was converted to an exponential decay time of 26.9 ± 0.04 s. This result is on the same order of magnitude of the photobleaching of immobilized Alexa 555 as reported previously by our group (75.6 ± 0.5 s). The differences in the observed times could be due to some desorption processes and that the current work did not use oxygen scavenger in solution that extends fluorescence lifetimes.[2, 3] References  Kisley, L., Chang, W.-S., Cooper, D., Mansur, A. P., Landes, C. F., Methods Appl. Fluoresc. 2013, 1, 037001.  Cooper, D., Uhm, H., Tauzin, L. J., Poddar, N., Landes, C. F., ChemBioChem 2013, 14, 1075-1080.  Ha, T., Tinnefeld, P., Annu. Rev. Phys. Chem. 2012, 63, 595-617.