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Queries bioRxiv/medRxiv preprints via REST API without authentication. Searches by DOI, category, or date range; returns metadata (title, abstract, authors, DOI) and PDFs.
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bioRxiv (biology) and medRxiv (health sciences) are free preprint servers hosting 200,000+ and 50,000+ manuscripts, respectively, before or alongside peer review. The unified REST API provides programmatic access to preprint metadata (title, abstract, authors, category, DOI, version history) without authentication. Preprints are available as PDF and can be retrieved by DOI, date range, or categ...
bioRxiv (biology) and medRxiv (health sciences) are free preprint servers hosting 200,000+ and 50,000+ manuscripts, respectively, before or alongside peer review. The unified REST API provides programmatic access to preprint metadata (title, abstract, authors, category, DOI, version history) without authentication. Preprints are available as PDF and can be retrieved by DOI, date range, or category.
pubmed-database; for all disciplines use openalex-databaserequests, pandaspip install requests pandas
import requests
BASE = "https://api.biorxiv.org"
# Retrieve recent bioinformatics preprints
r = requests.get(f"{BASE}/details/biorxiv/2024-01-01/2024-01-07/0",
params={"category": "bioinformatics"})
r.raise_for_status()
data = r.json()
print(f"Total preprints: {int(data['messages'][0]['total'])}") # API returns total as a string
for article in data["collection"][:3]:
print(f"\n{article['title'][:80]}")
print(f" Authors : {article['authors'][:60]}")
print(f" DOI : {article['doi']}")
print(f" Category: {article['category']}")
Retrieve all preprints posted within a date range, optionally filtered by category.
import requests, pandas as pd
BASE = "https://api.biorxiv.org"
def get_preprints(server, date_from, date_to, cursor=0, category=None):
"""
server: 'biorxiv' or 'medrxiv'
date_from, date_to: 'YYYY-MM-DD' strings
cursor: page offset (increments of 100)
"""
url = f"{BASE}/details/{server}/{date_from}/{date_to}/{cursor}"
r = requests.get(url)
r.raise_for_status()
return r.json()
data = get_preprints("biorxiv", "2024-01-01", "2024-01-03")
total = int(data["messages"][0]["total"]) # API returns total as a string — cast for arithmetic
print(f"bioRxiv preprints Jan 1-3, 2024: {total}")
rows = []
for article in data["collection"][:10]:
rows.append({
"doi": article["doi"],
"title": article["title"],
"authors": article["authors"][:80],
"category": article["category"],
"date": article["date"],
"version": article["version"],
})
df = pd.DataFrame(rows)
print(df[["title", "category", "date"]].head())
# Paginate through all results for a date range
def get_all_preprints(server, date_from, date_to, max_results=500):
all_articles = []
cursor = 0
while len(all_articles) < max_results:
data = get_preprints(server, date_from, date_to, cursor)
collection = data["collection"]
if not collection:
break
all_articles.extend(collection)
total = int(data["messages"][0]["total"]) # cast: API returns total as string
cursor += 100
if cursor >= total:
break
return all_articles[:max_results]
articles = get_all_preprints("biorxiv", "2024-01-01", "2024-01-07")
print(f"Retrieved {len(articles)} preprints from first week of 2024")
Retrieve full metadata and version history for a specific preprint by DOI.
import requests
BASE = "https://api.biorxiv.org"
# Retrieve specific preprint by DOI
doi = "10.1101/2024.01.01.000001" # Replace with real DOI
def get_by_doi(server, doi):
r = requests.get(f"{BASE}/details/{server}/{doi}")
r.raise_for_status()
return r.json()
# Generic example using bioRxiv DOI pattern
r = requests.get(f"{BASE}/details/biorxiv/10.1101/2024.05.28.596311")
if r.ok:
data = r.json()
articles = data.get("collection", [])
if articles:
art = articles[-1] # Latest version
print(f"Title : {art['title']}")
print(f"Authors : {art['authors'][:100]}")
print(f"Category: {art['category']}")
print(f"Date : {art['date']}")
print(f"Version : {art['version']}")
print(f"DOI : {art['doi']}")
print(f"Abstract (first 300): {art['abstract'][:300]}")
Check if a preprint has been published in a peer-reviewed journal.
import requests
BASE = "https://api.biorxiv.org"
def check_published(server, doi):
"""Check if a preprint DOI has a corresponding published article."""
r = requests.get(f"{BASE}/publisher/{server}/{doi}")
r.raise_for_status()
data = r.json()
return data.get("collection", [])
# Check one known preprint
doi = "10.1101/2024.05.28.596311"
published = check_published("biorxiv", doi)
if published:
pub = published[0]
print(f"Published in: {pub.get('published_journal')}")
print(f"Published DOI: {pub.get('published_doi')}")
else:
print(f"Preprint {doi} has not been published yet (or not tracked)")
Monitor preprints by specific research category.
import requests, pandas as pd
from datetime import date, timedelta
BASE = "https://api.biorxiv.org"
# bioRxiv categories include: bioinformatics, genomics, neuroscience,
# immunology, cell-biology, biochemistry, microbiology, etc.
def weekly_category_digest(category, days_back=7):
"""Get preprints from last N days for a specific category."""
today = date.today()
date_from = (today - timedelta(days=days_back)).strftime("%Y-%m-%d")
date_to = today.strftime("%Y-%m-%d")
all_articles = []
cursor = 0
while True:
r = requests.get(f"{BASE}/details/biorxiv/{date_from}/{date_to}/{cursor}")
data = r.json()
batch = [a for a in data["collection"] if category.lower() in a["category"].lower()]
all_articles.extend(batch)
if len(data["collection"]) < 100:
break
cursor += 100
return pd.DataFrame(all_articles)[["doi", "title", "authors", "date"]] if all_articles else pd.DataFrame()
df = weekly_category_digest("genomics", days_back=3)
print(f"Recent genomics preprints: {len(df)}")
print(df[["title", "date"]].head())
Query medRxiv for health and clinical science preprints.
import requests, pandas as pd
BASE = "https://api.biorxiv.org"
# medRxiv categories: infectious diseases, epidemiology, oncology,
# cardiology, neurology, psychiatry, public and global health, etc.
r = requests.get(f"{BASE}/details/medrxiv/2024-01-01/2024-01-07/0")
r.raise_for_status()
data = r.json()
total = int(data["messages"][0]["total"]) # cast: API returns total as string
print(f"medRxiv preprints Jan 1-7, 2024: {total}")
# Group by category
from collections import Counter
category_counts = Counter(a["category"] for a in data["collection"])
print("\nTop categories:")
for cat, count in category_counts.most_common(5):
print(f" {cat}: {count}")
Retrieve abstracts for a list of bioRxiv DOIs.
import requests, time, pandas as pd
BASE = "https://api.biorxiv.org"
dois = [
"10.1101/2024.05.28.596311",
"10.1101/2023.11.28.569048",
"10.1101/2023.03.07.531523",
]
rows = []
for doi in dois:
r = requests.get(f"{BASE}/details/biorxiv/{doi}")
if r.ok:
collection = r.json().get("collection", [])
if collection:
art = collection[-1] # Latest version
rows.append({
"doi": doi,
"title": art.get("title"),
"category": art.get("category"),
"date": art.get("date"),
"abstract": art.get("abstract", "")[:300],
})
time.sleep(0.2)
df = pd.DataFrame(rows)
if not df.empty:
df.to_csv("preprint_abstracts.csv", index=False)
print(df[["doi", "title", "category"]].to_string(index=False))
else:
print("No valid preprints found for provided DOIs")
The bioRxiv API follows the pattern: https://api.biorxiv.org/details/{server}/{interval}/{cursor}
server: biorxiv or medrxivinterval: either a DOI (for single record) or date_from/date_to (for date range)cursor: pagination offset (0, 100, 200…)Preprints can be updated; each update creates a new version (v1, v2, v3…). The API returns all versions chronologically; the last item in collection is always the most recent.
Goal: Automatically collect last week's preprints in target categories and export for review.
import requests, time, pandas as pd
from datetime import date, timedelta
BASE = "https://api.biorxiv.org"
TARGET_CATEGORIES = ["bioinformatics", "genomics", "systems biology"]
DAYS_BACK = 7
today = date.today()
date_from = (today - timedelta(days=DAYS_BACK)).strftime("%Y-%m-%d")
date_to = today.strftime("%Y-%m-%d")
print(f"Fetching bioRxiv preprints from {date_from} to {date_to}")
all_articles = []
cursor = 0
while True:
r = requests.get(f"{BASE}/details/biorxiv/{date_from}/{date_to}/{cursor}")
r.raise_for_status()
data = r.json()
batch = data["collection"]
if not batch:
break
all_articles.extend(batch)
total = int(data["messages"][0]["total"]) # cast: API returns total as string
cursor += 100
if cursor >= total:
break
time.sleep(0.1)
# Filter by target categories
filtered = [a for a in all_articles
if any(cat in a.get("category", "").lower() for cat in TARGET_CATEGORIES)]
df = pd.DataFrame(filtered)[["doi", "title", "authors", "category", "date"]]
df = df.drop_duplicates(subset="doi") # Remove duplicate versions
output_file = f"biorxiv_digest_{date_to}.csv"
df.to_csv(output_file, index=False)
print(f"\nSaved {len(df)} preprints across {len(TARGET_CATEGORIES)} categories → {output_file}")
print(df[["title", "category", "date"]].head(5).to_string(index=False))
Goal: For a list of preprint DOIs, check which have been published and retrieve publication details.
import requests, time, pandas as pd
BASE = "https://api.biorxiv.org"
preprint_dois = [
"10.1101/2024.05.28.596311",
"10.1101/2023.11.28.569048",
]
results = []
for doi in preprint_dois:
# Get preprint metadata
r_meta = requests.get(f"{BASE}/details/biorxiv/{doi}")
meta = {}
if r_meta.ok and r_meta.json().get("collection"):
art = r_meta.json()["collection"][-1]
meta = {"title": art["title"], "category": art["category"],
"preprint_date": art["date"]}
# Check publication status
r_pub = requests.get(f"{BASE}/publisher/biorxiv/{doi}")
published = {}
if r_pub.ok and r_pub.json().get("collection"):
pub = r_pub.json()["collection"][0]
published = {"journal": pub.get("published_journal"),
"pub_doi": pub.get("published_doi")}
results.append({"preprint_doi": doi, **meta, **published})
time.sleep(0.25)
df = pd.DataFrame(results)
print(df.to_string(index=False))
df.to_csv("preprint_publication_status.csv", index=False)
| Parameter | Module | Default | Range / Options | Effect |
|---|---|---|---|---|
server | URL path | required | "biorxiv", "medrxiv" | Select preprint server |
date_from | URL path | required | "YYYY-MM-DD" | Start of date range |
date_to | URL path | required | "YYYY-MM-DD" | End of date range |
cursor | URL path | 0 | 0, 100, 200… | Pagination offset (100 per page) |
category | Filter | — | e.g., "bioinformatics" | Category name substring match (post-filter) |
version | — | all versions | — | API returns all versions; use [-1] for latest |
Always take the last element for latest version: The collection array is sorted oldest-to-newest version. Use collection[-1] to get the most current version of a preprint.
Post-filter by category: The API does not natively filter by category; retrieve all preprints for a date range and filter client-side using if category in article["category"].lower().
Respect server resources: Add time.sleep(0.2) between individual DOI lookups; avoid bulk hammering the API.
Cross-check with PubMed: The publisher endpoint reveals when a preprint is published; use pubmed-database to retrieve the full peer-reviewed article metadata.
Handle missing abstracts: Some preprints have empty abstract fields. Always guard with art.get("abstract", "") or "No abstract available".
When to use: Retrieve full-text PDF for a bioRxiv preprint. Caveat: as of 2026, www.biorxiv.org is fronted by Cloudflare's anti-bot challenge — direct requests.get(..., headers={"User-Agent": "Mozilla/5.0"}) consistently returns HTTP 403 ("Just a moment...") even with a Session and a landing-page warmup. The pattern below attempts a best-effort download with realistic browser headers, then falls back to EuropePMC for metadata if blocked.
import requests
def download_biorxiv_pdf(doi, out_path=None):
"""Best-effort PDF download. If Cloudflare blocks, return False so the caller
can fall back to EuropePMC metadata or open the landing page in a browser."""
pdf_url = f"https://www.biorxiv.org/content/{doi}.full.pdf"
s = requests.Session()
s.headers.update({
"User-Agent": ("Mozilla/5.0 (X11; Linux x86_64) AppleWebKit/537.36 "
"(KHTML, like Gecko) Chrome/124.0.0.0 Safari/537.36"),
"Accept": "text/html,application/xhtml+xml,application/xml;q=0.9,application/pdf,*/*;q=0.8",
"Accept-Language": "en-US,en;q=0.5",
})
# Warm up the landing page first (sometimes lets Cloudflare's "trust" cookie set)
s.get(f"https://www.biorxiv.org/content/{doi}v1", timeout=30)
r = s.get(pdf_url, timeout=60)
if r.ok and r.content.startswith(b"%PDF"):
out = out_path or f"{doi.replace('/', '_')}.pdf"
with open(out, "wb") as f:
f.write(r.content)
print(f"Downloaded {out} ({len(r.content)//1024} KB)")
return True
print(f"PDF blocked (HTTP {r.status_code}); falling back to metadata-only via EuropePMC")
return False
def europepmc_metadata(doi):
"""Fetch preprint metadata via EuropePMC when bioRxiv PDF is blocked.
EuropePMC indexes bioRxiv as source 'PPR' and exposes a stable landing URL."""
r = requests.get("https://www.ebi.ac.uk/europepmc/webservices/rest/search",
params={"query": f"DOI:{doi}", "format": "json"}, timeout=30)
r.raise_for_status()
hits = r.json().get("resultList", {}).get("result", [])
if not hits:
return None
h = hits[0]
return {
"source": h.get("source"), # 'PPR' for preprints
"epmc_id": h.get("id"), # e.g. 'PPR860608'
"title": h.get("title"),
"landing_url": f"https://europepmc.org/article/{h.get('source')}/{h.get('id')}",
}
doi = "10.1101/2024.05.28.596311"
if not download_biorxiv_pdf(doi):
meta = europepmc_metadata(doi)
print(f" EuropePMC landing: {meta['landing_url']}")
print(f" Title: {meta['title'][:80]}")
When to use: Analyze the distribution of preprints across bioRxiv categories in a time window.
import requests, pandas as pd
from collections import Counter
r = requests.get("https://api.biorxiv.org/details/biorxiv/2024-01-01/2024-01-07/0")
data = r.json()
total = int(data["messages"][0]["total"]) # cast: API returns total as a string
# Fetch all pages
all_articles = data["collection"]
for cursor in range(100, min(total, 1000), 100):
r2 = requests.get(f"https://api.biorxiv.org/details/biorxiv/2024-01-01/2024-01-07/{cursor}")
all_articles.extend(r2.json()["collection"])
counts = Counter(a["category"] for a in all_articles)
df = pd.DataFrame(counts.most_common(), columns=["category", "count"])
print(df.head(10).to_string(index=False))
When to use: Quick single-preprint publication check.
import requests
doi = "10.1101/2024.05.28.596311"
r = requests.get(f"https://api.biorxiv.org/publisher/biorxiv/{doi}")
collection = r.json().get("collection", [])
if collection:
print(f"Published: {collection[0]['published_journal']} | DOI: {collection[0]['published_doi']}")
else:
print("Not published or not tracked")
| Problem | Cause | Solution |
|---|---|---|
collection is empty | DOI not found or date range has no results | Verify DOI format (starts with 10.1101/); check date range |
| Duplicate preprints in results | Multiple versions returned | Deduplicate by DOI: df.drop_duplicates(subset='doi', keep='last') |
| Missing abstract field | Some preprints don't have structured abstracts | Guard with art.get("abstract", "") or "N/A" |
total count vs retrieved mismatch | New preprints added during pagination | Accept approximate totals; preprints are added continuously |
| PDF download blocked (HTTP 403 "Just a moment...") | Cloudflare anti-bot on www.biorxiv.org/.../*.full.pdf (cannot be bypassed by a Mozilla/5.0 UA alone, nor by a Session + landing-page warmup) | Try the Session + warmup recipe; if still blocked, fall back to EuropePMC (source=PPR) for metadata, or fetch the PDF interactively from the bioRxiv landing page in a browser |
cursor >= total never triggers; loop runs forever | data['messages'][0]['total'] is returned as a string (e.g. '1119'); int_cursor >= str_total raises TypeError or compares lexically | Cast explicitly: int(data["messages"][0]["total"]) in every pagination loop |
collection empty for a specific DOI | The DOI never resolved to a real preprint (e.g. fake placeholder like 2023.01.01.000001, or a stale/withdrawn DOI) | Verify the DOI on https://www.biorxiv.org/content/{doi}v1 first; recent DOIs from a date-range listing are the safest examples |
| Slow pagination for large date ranges | Large number of preprints | Use narrower date windows (3-7 days) for busy periods |
pubmed-database — Peer-reviewed biomedical literature for verifying published versions of preprintsopenalex-database — Broader scholarly index including bioRxiv content after indexing lagliterature-review — Guide for incorporating preprints into systematic reviewsscientific-brainstorming — Using preprint alerts as input for hypothesis generationnpx claudepluginhub jaechang-hits/sciagent-skills --plugin sciagent-skillsSearches and retrieves preprints from bioRxiv by keywords, authors, date ranges, or categories. Supports metadata extraction and PDF downloads for literature reviews.
Searches bioRxiv preprints by keywords, authors, DOI, date ranges, or categories and retrieves metadata or downloads PDFs. Useful for life sciences literature reviews.
Fetches and keyword-filters preprints from bioRxiv/medRxiv within a date window. Handles pagination, deduplication, and normalization.