A solution for removal of resin from epoxy sections

Area of Science:

• Biomedical research
• Histopathology
• Materials science

Background:

• Epoxy resins like Epon 812 are commonly used for embedding biological tissues, including kidney biopsies.
• Complete removal of embedding resin is crucial for effective histological staining and accurate diagnosis.
• Existing resin removal methods often require harsh conditions or are time-consuming.

Purpose of the Study:

• To develop an efficient and mild solution for dissolving Epon 812 resin from tissue specimens.
• To evaluate the effectiveness of the developed solution in complete resin removal.
• To assess the compatibility of the resin removal process with standard histopathological staining techniques.

Main Methods:

• A novel solution was formulated by dissolving crown ether in dimethyl-sulfoxide (DMSO) to generate a superbasic alkoxide anion.
• Kidney biopsy specimens embedded in Epon 812 were treated with the developed solution for five minutes.
• Treated specimens were stained using Loeffler's methylene blue, periodic acid-methenamine silver (PAS), and Giemsa stains.
• Periodic acid-Schiff (PAS) reaction followed by hematoxylin counterstaining was also performed.

Main Results:

• The developed solution achieved complete removal of Epon 812 resin within a five-minute treatment period.
• Tissue specimens retained their structural integrity after resin dissolution.
• Staining with Loeffler's methylene blue, PAS, and Giemsa yielded good results.
• The PAS reaction and hematoxylin counterstaining were practicable for diagnostic purposes.

Conclusions:

• A novel, low-alkali resin-dissolving solution using crown ether in DMSO is effective for Epon 812 removal.
• This method offers a rapid and efficient approach to prepare kidney biopsy specimens for histopathological analysis.
• The technique preserves tissue morphology and is compatible with multiple diagnostic stains, facilitating accurate diagnosis.