# Preprint shows AI agents improving protein binders through repeated lab tests

_Published Wednesday, October 21, 2026 at 4:08 AM EDT · Science, AI · Latest · Tier 2 — Notable_

AI agents improved the share of molecular candidates that bound target proteins over three rounds of design and laboratory testing, researchers report in a preprint. The experiment used aptamers, molecules designed to bind proteins, against α-thrombin and myoglobin.

Bead-corrected on-target hit rates for new α-thrombin candidates rose from 0.0% to 26.0% and then 42.1%; the final rate was 37.1% excluding descendants of published motifs. Myoglobin hit rates moved from 10.2% to 3.7% and then 33.5%.

The agents also used experimental feedback to diagnose cross-reactivity and restore myoglobin specificity from 19.1% to 72.4%. However, newly designed scaffolds showed weaker binding than agent-engineered versions of published motifs in α-thrombin assays.

## Sources

- [cs.AI updates on arXiv.org](https://arxiv.org/abs/2610.24806)

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Canonical: https://techandbusiness.org/newswire/-LmFgSGlnhNdCNxka1_YNt
Published: 2026-10-21T08:08:15.948Z
Story chronology: 2026-10-21T04:00:00.000Z
Retrieved: 2026-10-25T06:21:42.275Z
Publisher: Tech & Business (techandbusiness.org)