Fig. 1.

Summary of a scanning ellipsometry-based detection of endpoints and real-time association–dissociation curves of protein probes with surface-immobilized targets in form of a large microarray on an epoxy-functionalized glass slide. The changes in thickness d and coverage Θ or surface mass density Γ of the target layer as a result of binding reaction cause extra changes in magnitude (Δr=r−r₀) and phase (Δδ=δ−δ₀) of an incident light beam (E₀) upon reflection from the target-covered surface. r₀ and δ₀ are magnitude and phase changes due to reflection from the “bare” glass surface in the absence of the target-probe layer. The present ellipsometry-based detection platform measures Δr and Δδ in real-time from all immobilized targets.