A reinforcement-learning agent that decides which measurement to buy next, and when to stop buying
AspireAI community · arXiv
Identifying a small molecule from tandem mass spectrometry often needs complementary measurements, and taking all of them is expensive. This work proposes a structure-informed deep Q-network that uses the existing mass-spectrometry evidence to decide whether further characterisation is needed, which measurement to request, and when to stop, combining spectral representations and candidate rankings with score-weighted descriptors of the candidates' chemical features and structural differences. It was evaluated on 79,462 held-out samples with simulated mass spectrometry, infrared and nuclear magnetic resonance spectra, using fixed hard candidate sets and equal normalised acquisition costs. Averaged across three training runs, top-1 accuracy rose from 80.10% to 93.78% for positive-ion starts and from 70.44% to 93.31% for negative-ion starts, with mean additional measurement counts of only 0.227 and 0.340 per sample; complete acquisition reached 97.72% accuracy with four additional measurements.
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