PAS Stain Service: Highlight Carbohydrates, Glycogen, and Fungi with Precision

At iHisto, we provide validated PAS staining (Periodic Acid–Schiff) for clear visualization of carbohydrates, glycoproteins, glycogen, mucins, and fungal cell walls. This technique is essential for renal and liver pathology, fungal infection analysis, and tumor subtyping in both research and clinical studies.

🧪 Overview 

The PAS stain detects carbohydrate-rich structures through a chemical oxidation and Schiff reaction, producing a vivid magenta color that sharply contrasts against nuclei and background.

Used in kidney, liver, GI, and tumor tissues, PAS staining is critical for:

• Identifying basement membranes

• Highlighting fungal organisms

• Detecting glycogen storage

• Visualizing mucin production

• Characterizing epithelial lesions

🎯 How PAS Staining Works 

1. Periodic acid oxidizes carbohydrate molecules to form aldehyde groups.

2. These aldehydes react with Schiff reagent, producing a bright magenta chromogen.

3. Optional hematoxylin counterstaining provides nuclear detail.

Color Results:

• Glycogen, mucins, basement membranes → magenta

• Fungi (e.g., Candida, Histoplasma) → magenta

• Nuclei → blue or purple

• Background → pale or clear

🧬 Step-by-Step Staining Process

1. Fixation and Sectioning – FFPE tissue cut at 4–6 µm

2. Deparaffinization and Hydration – Slides processed into distilled water

3. Oxidation with Periodic Acid – Converts carbohydrates to aldehydes

4. Schiff Reagent Application – Forms magenta-colored sites

5. Counterstaining – Hematoxylin added for nuclei

6. Dehydration and Coverslipping – Slides cleared and sealed for review

⚙️ Our Optimized Workflow 

iHisto uses a semi-automated staining workflow for consistency and reproducibility:

• Leica ST5020 Autostainer – Uniform reagent application

• TS5025 Transfer Station – Controlled reaction timing

• CV5030 Coverslipper – Crisp slide sealing and minimal artifacts

We maintain optimal magenta intensity and minimal background staining.

🔬 Applications of PAS Staining 

Common use cases include:

• Renal biopsies – Glomerular basement membrane (GBM), brush borders

• Liver pathology – Glycogen accumulation, alpha-1-antitrypsin globules

• Fungal detection – Candida, Aspergillus, Histoplasma identification

• GI pathology – Barrett’s esophagus, mucin-secreting tumors

• Tumor analysis – PAS-positive adenocarcinomas and other mucinous lesions

Also available with PAS-D (diastase digestion) to remove glycogen for enhanced specificity.

✅ Why Choose iHisto 

• ✅ Brilliant magenta staining of glycogen, mucin, and fungal walls

• ✅ Compatible with PAS-D for glycogen differentiation

• ✅ Works with human, rodent, and NHP tissue

• ✅ High-resolution digital slide scanning available

• ✅ Optional pathologist interpretation and semi-quant scoring

iHisto provides rapid, reliable PAS staining to support your pathology, infectious disease, or metabolic research.

❓ FAQs 

• What does PAS stain detect?
  Carbohydrates, glycogen, mucins, basement membranes, and fungal cell walls.

• What is the difference between PAS and PAS-D?
  PAS-D includes diastase treatment, which digests glycogen — allowing better visualization of non-glycogen targets like mucins or fungal walls.

• Is PAS used in kidney and liver pathology?
  Yes — it's a cornerstone stain for GBM analysis, glycogen storage diseases, and inclusion body detection.

• Can I get scanned slides?
  Absolutely. We offer whole-slide imaging with secure cloud or USB delivery.

📩 Request a Quote or Consultation

Whether you're analyzing basement membranes, diagnosing fungal infections, or classifying tumors, iHisto’s PAS staining delivers clarity and confidence — every time.

👉 Request a Quote or email info@ihisto.io