Knowledge Base › Troubleshooting Atlas › Special stains
Masson trichrome collagen not staining
What it looks like
Collagen appears blue, muscle and cytoplasm appear red. Poor staining may show pale or absent blue areas where collagen should be.
Where it usually appears: Commonly used in tissue sections to visualize collagen in various connective tissues and fibrotic lesions.
Likely causes
- Inadequate fixation of tissue
- Improper pH of staining solutions
- Old or degraded reagents
- Insufficient staining time
- Inaccurate dilution of reagents
Immediate checks
- Verify fixation time and method
- Check pH of staining solutions
- Inspect reagents for expiration or degradation
Corrective action
- Re-fix tissue samples if inadequate
- Adjust pH of solutions as needed
- Replace old reagents
- Increase staining time for better results
Preventive action
- Regularly check and replace reagents
- Ensure proper fixation protocols are followed
- Maintain accurate pH levels in solutions
This atlas is for educational purposes for laboratory professionals. It does not replace your institutional SOPs, manufacturer instructions, validated protocols or pathologist judgment. Adapt any action to your laboratory and equipment.
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