Figure 1.

Transport rates of 200 nm PEG-modified PS particles with high surface coverage 2 kDa PEG (PS-PEG2k^High) or high surface coverage 10 kDa PEG (PS-PEG10k^High) in CVM. a) Ensemble-averaged geometric mean square displacements (〈MSD〉) as a function of time scale. b) Distributions of the logarithms of individual particle effective diffusivities (D_eff) at a time scale of 1 s. Data represent five independent experiments with n ≥ 100 particles per experiment (average n=141 and 127 for PS-PEG2k^High and PS-PEG10k^High, respectively). c) Ratios of the ensemble average diffusion coefficients in mucus (D_m) compared to in water (D_w) for PS-PEG particles with PEG of varying MW. Particles synthesized with a similarly dense coating of 5 kDa methoxy-PEG-amine (PS-PEG5k^High) had an average size of (238±4) nm and ζ-potential of (-6±1) mV. Data represent three independent experiments with n≥150 particles per experiment for PS-PEG5k^High.