Protein Desorption Kinetics Depends on the Timescale of Observation

Abstract

The presence of so-called reversible and irreversible protein adsorption on solid surfaces is well documented in the literature and represents the basis for the development of nanoparticles and implant materials to control interactions in physiological environments. Here, using a series of complementary single-molecule tracking approaches appropriate for different timescales, we show that protein desorption kinetics is much more complex than the traditional reversible–irreversible binary picture. Instead, we find that the surface residence time distribution of adsorbed proteins transitions from power law to exponential behavior when measured over a large range of timescales (10–2–106 s). A comparison with macroscopic results obtained using a quartz crystal microbalance suggested that macroscopic measurements have generally failed to observe such nonequilibrium phenomena because they are obscured by ensemble-averaging effects. These findings provide new insights into the complex phenomena associated with protein adsorption and desorption.

Pore Size Dependence of Mass Transfer of Zinc Myoglobin in a Single Mesoporous Silica Particle

“…Wang et al reported the k d value of bovine serum albumin on the gold surface as 2.24 × 10 −3 s −1 . 51 This previous report supports that the slow desorption of ZnMb suppresses intraparticle diffusion in SP 30 and SP 50 in both processes.…”

“…The corresponding simulated D p in Table is obtained when the k d is approximately 0.01–0.001 s –1 , indicating that the k d of ZnMb on the silica surface is of 10 –3 s –1 order. Wang et al reported the k d value of bovine serum albumin on the gold surface as 2.24 × 10 –3 s –1 . This previous report supports that the slow desorption of ZnMb suppresses intraparticle diffusion in SP 30 and SP 50 in both processes.…”

“…This indicated that the desorption rate of proteins becomes slower compared to that of small molecules. 51 We predicted that the difference in the D p in both processes of SP 30 and SP 50 might be due to the slow desorption rate of ZnMb. Pore diffusion is suppressed when the desorption of ZnMb is slow because pore diffusion occurs through adsorption and desorption on the surface.…”

Mechanistic Understanding of Protein Corona Formation around Nanoparticles: Old Puzzles and New Insights

“…In reality, however, binding parameters are broadly distributed due to protein and NP surface heterogeneity, as was vividly shown by studies of individual adsorption events. [89] Structure-based computational modeling and simulation can also provide valuable insights into conformational changes of biomolecules interacting with surfaces. [97][98][99][100][101] At this stage, however, there are still severe challenges that need to be overcome to achieve realistic simulations of the adsorption process over longer times.…”

Single-Molecule Tracking of Reagent Diffusion during Chemical Reactions

“…This makes SMT very suitable for acquiring the precise value of D in different timescales . The SMT enabled the scientists to understand details about, for example, the polymerization, the molecular movement in cells, − and dynamics in complex environments, − at the plasma membranes, − and on solid–liquid − and liquid–liquid , interfaces. Because SMT is essentially an imaging method, this technique can circumvent the inconsistent signal fitting and interpretation ,, and rule out concerns in which photophysical artifacts , and bulk fluid convection were erroneously interpreted as the variation of D .…”