Get started
List mass candidates in Duaer
In Duaer, list PubChem compounds that fit an observed m/z and adduct. One successful search uses 1 credit.
What you get
Mass candidates in the Duaer data market uses 1 credit per successful search, including a search with no match.
Each candidate has a ppm error and InChIKey; mass alone does not identify a structure.
To work an unknown feature step by step, see Annotate an unknown feature with Duaer.
Search on the canvas
- Open the node creator, pick Duaer Data → Mass candidates.
- Fill m/z.
- Pick Adduct (default [M+H]+); optional Tolerance (ppm), default 5.
- Limit defaults to 10, max 20. Execute.
A successful search uses 1 credit. Empty input or a failed source uses 0.
Call the API
- GET https://api.duaer.com/v1/data/mass-candidates?...
- Authorization: Bearer <Duaer key>
The call skill below matches Copy skill.
Call skill
Same text as Copy skill.
---
name: duaer-mass-candidates
description: >-
List PubChem compounds that fit an observed m/z and adduct through Duaer.
One successful search uses 1 Duaer credit.
---
# Duaer mass candidates
Turn an observed m/z into candidate compounds from PubChem through Duaer with a Duaer key.
## Call
`GET https://api.duaer.com/v1/data/mass-candidates?mz=181.0707&adduct=%5BM%2BH%5D%2B&ppm=5&limit=10`
Header: `Authorization: Bearer <Duaer key>`
Use an account key or a model API key.
Get a Duaer key: https://skills.duaer.com/keys.md
`mz` is required.
- `mz` — observed m/z of the feature.
- `adduct` — optional. `neutral`, `[M+H]+`, `[M+Na]+`, `[M+NH4]+`, `[M+K]+`, `[M+H-H2O]+`, `[M-H]-`, `[M+Cl]-`, or `[M+FA-H]-`. Default `[M+H]+`.
- `ppm` — optional. Mass tolerance in ppm, up to 100. Default 5.
- `limit` — optional. From 1 to 20. Default 10.
## Result
Each item has `source`, `title`, `url`, `summary`, `cid`, `formula`, `monoisotopicMass`, `neutralMass`, `ppmError`, `inchikey`, and `iupacName`.
Candidates come in PubChem relevance order. Check a candidate's reference spectra with https://skills.duaer.com/mona.md or https://skills.duaer.com/massbank.md (`inchikey`).
To work an unannotated feature step by step, follow https://skills.duaer.com/metabolic-dark-matter.md.
## Credits
One successful search uses 1 credit, including a search that finds no match.
Empty input, a failed source, or no remaining credits uses 0.
No remaining credits returns 402 and does not search.
A missing key returns 401.
Questions
How many credits does a Mass candidates search use in Duaer?
One successful search uses 1 credit, including a search with no match. Empty input or a failed source uses 0.
In this section
Annotate an unknown feature with Duaer
In Duaer, work an MS feature that no library identified: library match, mass candidates, reference spectra, and MASST, one Duaer Data call per step.
Get startedFind MoNA reference spectra with Duaer
In Duaer, find reference MS/MS spectra in MoNA by InChIKey or compound name. One successful search uses 1 credit.
Get startedSearch compounds in Duaer
In Duaer, search compounds and drugs with Duaer Data. One successful search uses 1 credit; a name that matches nothing uses 0. This page includes the full English call skill.