Figure 5 |.

Reactivity of backbone-selective versus endgroup selective APAs toward EG2-OMe, EG3-OMe, and EG5-OMe POEGMA brushes. a, Schematic of backbone-selective (blue) versus endgroup-selective (tan) APA binding to PEG backbone and methoxy terminus of a bottlebrush, respectively. b, Schematic of surface fluoroimmunoassay for APA binding. Surfaces were incubated with a solution of APA-spiked calf serum, then labeled with Cy5-conjugated dAbs, and then read with a scanner. c–f, Reactivity of polyclonal APAs toward bottlebrush surfaces with known selectivity for PEG endgroups (pAPA1) versus backbone (pAPA2) (c, d), and similar plots shown for endgroup-selective (e-mAPA) versus backbone-selective (b-mAPA) monoclonal APAs (e, f) as assessed by surface fluoroimmunoassays. Data are plotted as mean fluorescence intensities ± s.d. (n = 9). Bars marked with different letters indicate significant differences by multiple comparison testing in one-way ANOVA (Tukey post hoc test, p ≤ 0.05).