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SELEX: In Vitro Aptamer Selection

Interactive SELEX simulator: watch a random-sequence oligonucleotide library evolve against a molecular target across rounds of Langmuir-isotherm binding, stringent partitioning and mutagenic PCR amplification, enriching for the tightest-binding aptamers.

Molecular Biology3DAdvanced60 FPS📱 Mobile-adapted⇄ 2D version

SELEX is the directed-evolution process used to discover DNA/RNA aptamers — folded nucleic-acid ligands that bind a target with antibody-like specificity. This simulator models a library of a few hundred candidate sequences, each with its own dissociation constant K_d, cycling through Langmuir-isotherm binding, stochastic stringent partitioning, and mutagenic PCR amplification. Tune the target concentration, wash stringency and mutation rate, run rounds one at a time or on auto-play, and watch the population's affinity distribution enrich round over round exactly as it does on the bench — with live readouts for mean and best K_d, per-round survival fraction, and total enrichment.

⚙ Under the hood

Run a random-sequence oligonucleotide library through rounds of Langmuir-isotherm target binding, stringent partitioning and mutagenic PCR amplification, and watch its affinity distribution enrich toward tight-binding aptamers exactly as in a real SELEX protocol.

aptamerSELEXmolecular biologyPCRbinding affinitydirected evolution

3D · Three.js / WebGL renderer · 60 FPS target · runs fully client-side, no install