FIG. 2.

Schematic diagram of the single-stranded DNA construct [5’-AACC(T₂₁)GGTT-3’] in an unfolded and a hairpin-folded conformation with fluorescent dye labels and immobilized on a polyethylene glycol coated coverslip via a biotin-streptavidin-biotin linkage. k_F and k_U are the folding and unfolding rate coefficients. The 2 thymines that form base pairs in the folded hairpin are distinguished by a darker shading.