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MALDI-MSI — Matrix-Assisted Laser Desorption/Ionization Mass-Spec Imaging L1-127

Scientific InstrumentationLaser-desorption mass-spec imaging of tissueδ=3 · standardL_DAG = 3📋 Stub — not mineable
📋

Unclaimed Principle — open for contribution

This Principle is declared in the catalog but has no reference solver, no pinned dataset, and is not registered on-chain. There is no reward pool. Submitting a cert against this Principle today will record the cert for reproducibility but pay zero PWM.

To claim it as a Bounty #7 contribution: open a PR adding (1) a reference solver, (2) ≥1 dataset pinned to IPFS, (3) updates to the L3 manifest with dataset CIDs. After verifier-agent triple-review, the founders' 3-of-5 multisig signs PWMRegistry.register() and the Principle becomes mineable.

Forward model E

A matrix compound (CHCA, DHB, SA) is co-crystallized with analyte; a pulsed UV or IR laser (N2 337 nm, Nd:YAG 355 nm) ionizes matrix-analyte clusters; positive or negative ions fly into a time-of-flight analyzer yielding m/z-resolved spectra per pixel. Ablation craters rastered to 5-50 um resolution.

L-DAG

S.desorb.laserMATRIX -> L.disperse.mass -> int.temporal
S.desorb.laserMATRIXL.disperse.massint.temporal

Well-posedness W

Existence:
true
Uniqueness:
peak ID unique; semi-quantitative (matrix-effects dominant)
Stability:
conditional
κ:
800

Counts-based Poisson noise; hot-spot variability and ion-suppression cause major between-pixel variance. Relative quantitation ok; absolute requires internal standards.

Solvability C

Solver class:
Peak integration, PCA/NMF, MCR-ALS, mass-recalibration, hot-spot correction, learned (CNN-MSI)
Convergence rate q:
2
Complexity:
PeakInt O(H*W*N_mz); CNN-MSI feed-forward

Specs (0)

No L2 specs registered yet for this principle.