structflo.ner

Zero-config Named Entity Recognition for drug discovery, chemistry, and biological sciences.

Installation • LLM Extraction • Fast NER • Profiles • Visualization • Notebooks

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structflo.ner is a lightweight NER library specialized for pharmaceutical and biological sciences. It uses LangExtract and fuzzy based tools to deliver zero-configuration entity extraction.

It ships with two extraction engines:

	NERExtractor	FastNERExtractor
Approach	LLM-powered (Gemini, Ollama)	Dictionary-based (YAML gazetteers)
Speed	~10-60s per abstract	~0.4-1s per abstract
Novel entities	Discovers new entities	Known terms only
Context awareness	Full contextual understanding	String matching (exact + fuzzy)
Cost	API costs or local GPU	Free (no API calls)
Setup	API key or Ollama	Zero config
Output format	NERResult	NERResult (identical)

Installation

pip install structflo-ner

# or with uv
uv add structflo-ner

Install optional extras as needed:

pip install "structflo-ner[dataframe]"   # pandas DataFrame support
pip install "structflo-ner[fast]"         # fast dictionary-based NER (rapidfuzz)

LLM-Powered Extraction

Cloud model (Gemini)

The default model is gemini-2.5-flash. Pass your API key or set the GEMINI_API_KEY environment variable.

from structflo.ner import NERExtractor

extractor = NERExtractor(api_key="YOUR_GEMINI_KEY")

result = extractor.extract(
    "Gefitinib (ZD1839) is a first-generation EGFR tyrosine kinase inhibitor "
    "with IC50 = 0.033 µM, approved for non-small cell lung cancer (NSCLC). "
    "Its SMILES is COc1cc2ncnc(Nc3ccc(F)c(Cl)c3)c2cc1OCCCN1CCOCC1."
)

Local models via Ollama

Run extraction entirely on your own hardware — no API key needed:

extractor = NERExtractor(
    model_id="qwen2.5:72b",
    model_url="http://localhost:11434",
    )
text = ("Gefitinib (ZD1839) is a first-generation EGFR inhibitor with IC50 = 0.033 µM approved for NSCLC."
        "Its SMILES is COc1cc2ncnc(Nc3ccc(F)c(Cl)c3)c2cc1OCCCN1CCOCC1.")
result = extractor.extract(text)
result

Any model served by Ollama works gemma, llama, mistral, qwen, deepseek, etc.

Render results as color-coded, interactive HTML directly in Jupyter notebooks:

To get a PANDAS dataframe.

result.to_dataframe()

TB specific extractor pass in the profile=TB

from structflo.ner import NERExtractor, TB

extractor = NERExtractor(
    model_id="qwen2.5:72b",
    model_url="http://localhost:11434",
    profile=TB,
    

text = (
    "Bedaquiline (TMC207) is a diarylquinoline that inhibits the "
    "mycobacterial ATP synthase subunit c encoded by atpE (Rv1305). "
    "It shows potent activity against Mycobacterium tuberculosis "
    "including MDR-TB and XDR-TB. This compound was identified through "
    "whole-cell screening and targets the energy metabolism pathway."
)
result = extractor.extract(text)
result

# Flat list of all entities
for entity in result.all_entities():
    print(f"{entity.entity_type:20s} | {entity.text}")

compound_name        | Bedaquiline
compound_name        | TMC207
target               | ATP synthase subunit c
disease              | MDR-TB
disease              | XDR-TB
accession_number     | Rv1305
functional_category  | energy metabolism pathway
screening_method     | whole-cell screening

Batch extraction

Pass a list of texts to extract from multiple documents at once:

texts = [
    "Imatinib inhibits BCR-ABL with IC50 = 0.6 µM in CML.",
    "Trastuzumab targets HER2 in breast cancer patients.",
    "Remdesivir (GS-5734) is an antiviral with EC50 = 0.77 µM against SARS-CoV-2.",
]

results = extractor.extract(texts)

--- Text 1 ---
  compound_name        | Imatinib
  target               | BCR-ABL
  disease              | CML
  bioactivity          | IC50 = 0.6 µM

--- Text 2 ---
  compound_name        | Trastuzumab
  target               | HER2
  disease              | breast cancer

--- Text 3 ---
  compound_name        | Remdesivir
  compound_name        | GS-5734
  disease              | SARS-CoV-2
  bioactivity          | EC50 = 0.77 µM

Fast Dictionary-Based NER (Mode 2)

FastNERExtractor uses curated YAML gazetteers with a three-phase matching strategy for deterministic, high-speed extraction when LLMs are not available. These run extremely fast, however they are fuzzy based matches to predefined patterns and so it does not understands context.

from structflo.ner.fast import FastNERExtractor

fast = FastNERExtractor()

text = (
    "Bedaquiline (TMC207) is a diarylquinoline that inhibits the "
    "mycobacterial ATP synthase subunit c encoded by atpE (Rv1305). "
    "It shows potent activity against Mycobacterium tuberculosis "
    "including MDR-TB and XDR-TB. This compound was identified through "
    "whole-cell screening and targets the energy metabolism pathway."
)

result = fast.extract(text)
result

How matching works

Phase	Method	What it catches
1	Exact match	Case-sensitive and normalized dictionary lookups with word-boundary enforcement
1b	Regex patterns	Auto-derived patterns from accession number seeds (Rv tags, UniProt, PDB, etc.)
2	Fuzzy match	Typos and minor variants via rapidfuzz (configurable threshold)

# Fuzzy matching catches typos
result = fast.extract("Bedaquilne showed activity against TB")
# "Bedaquilne" -> canonical: "Bedaquiline" (method: fuzzy)

# Disable fuzzy matching for strict mode
strict = FastNERExtractor(fuzzy_threshold=0)

Built-in gazetteers

The fast extractor ships with curated gazetteers for TB drug discovery:

Gazetteer	Examples
accession_number	Rv1305, B586_RS00005
gene_name	atpE, InhA, DprE1
screening_method	whole-cell screening, fragment-based screening
target	InhA, DprE1, MmpL3
compound_name	Bedaquiline, Delamanid, Pretomanid
functional_category	DNA replication, cell wall biosynthesis
strain	M. tuberculosis H37Rv
product	enoyl-ACP reductase, ATP synthase subunit c
disease	TB, MDR-TB, XDR-TB

Custom gazetteers

Extend the built-in dictionaries with your own terms:

custom = FastNERExtractor(
    extra_gazetteers={
        "target": ["MyNovelTarget", "KinaseX"],
        "compound_name": ["CompoundABC"],
    }
)

Or drop a new YAML file into the gazetteers directory — the filename (without .yml) maps to an entity type.

Performance

Single abstract:  ~393 ms
8 abstracts:      ~862 ms

Profiles

Profiles control which entity types are extracted. Use them to focus the model on specific categories.

Built-in profiles

Profile	Entity classes
FULL (default)	compounds, targets, diseases, bioactivities, assays, mechanisms
CHEMISTRY	compound names, SMILES, CAS numbers, molecular formulas
BIOLOGY	targets, gene names, protein names
BIOACTIVITY	bioactivity measurements, assays
DISEASE	diseases and clinical indications
TB	TB drug discovery (compounds, targets, diseases, accessions, strains, screening methods, functional categories)

from structflo.ner import NERExtractor, CHEMISTRY

extractor = NERExtractor(api_key="YOUR_GEMINI_KEY")
result = extractor.extract(text, profile=CHEMISTRY)

Merging profiles

Combine multiple profiles for broader extraction:

from structflo.ner import CHEMISTRY, BIOLOGY

combined = CHEMISTRY.merge(BIOLOGY)
result = extractor.extract(text, profile=combined)
# Profile: chemistry+biology
# Entity classes: compound_name, smiles, cas_number, molecular_formula, target, gene_name, protein_name

Custom profiles

Define your own extraction schema:

from structflo.ner import NERExtractor, EntityProfile

my_profile = EntityProfile(
    name="kinase_inhibitors",
    entity_classes=["compound_name", "smiles", "target", "bioactivity"],
    prompt="Extract kinase inhibitor names, SMILES, targets, and potency values.",
    examples=my_examples,
)
result = extractor.extract(text, profile=my_profile)

Working with Results

Both extractors return identical NERResult objects:

# Typed entity lists
result.compounds        # [ChemicalEntity(...)]
result.targets          # [TargetEntity(...)]
result.diseases         # [DiseaseEntity(...)]
result.bioactivities    # [BioactivityEntity(...)]
result.assays           # [...]
result.mechanisms       # [...]
result.accessions       # [AccessionEntity(...)]

# Flat list of all entities
result.all_entities()

# Export to pandas DataFrame
df = result.to_dataframe()

# Serialize to dict (JSON-friendly)
result.to_dict()

Notebooks

Explore worked examples in the notebooks/ directory:

Notebook	Description
01_quickstart.ipynb	End-to-end extraction with cloud and local models, profiles, batch extraction
02_fast_ner.ipynb	Fast dictionary-based NER — matching strategies, custom gazetteers, performance

Contributing

Pull requests are welcome. For major changes, please open an issue first to discuss what you would like to change.

# clone and install dev dependencies
git clone https://github.com/structflo/structflo-ner.git
cd structflo-ner
pip install -e ".[dataframe]" --group dev

# run tests
pytest

# lint
ruff check .
ruff format .

Citation

If you use structflo.ner in your research, please cite:

BibTeX

@software{structflo_ner,
  title  = {structflo.ner: Zero-config NER for Drug Discovery},
  url    = {https://github.com/structflo/structflo-ner},
  year   = {2026}
}

License

This project is licensed under the Apache License 2.0.