Fig. 1. (A) Bilingual PNAs having amphiphilic side chains at the γ-position to direct self-assembly and a nucleotide sequence to direct disassembly through recognition of a complementary masking sequence. The hydrophobic group (R₁) drives self-assembly by inducing aggregation, while the hydrophilic group (R₂) increases solubility. (B) Stimuli-responsive assembly through toehold-mediated displacement of the masking strand.