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bioRxiv · 10.1101/2025.05.01.651707

STREAMLINING HISTOPATHOLOGY: INSTAPRESERVE TISSUESAFE A SINGLE-STEP FIXATIVE THAT IMPROVES TISSUE QUALITY AND WORKFLOW EFFICIENCY

Vangala, R. K.·Vangala, A. B.·Kanukollu, S.·Sankarnarayanan, P. M.·Shankar, A.·Murugaian, E. E.
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Abstract

In clinical pathology, tissue processing is crucial in generating a valuable report for faster diagnosis. Formalin-fixed paraffin-embedded tissues are the standard specimens for clinical and molecular analyses. Though the demand persists for faster diagnosis, neutral buffered formalin (NBF) -based fixation and processing have not been replaced with a simple, faster, and user-friendly method. The alcohol-based fixatives were evaluated as an alternative to formalin, yet none have replaced formalin for various reasons. InstaPRESERVE Tissuesafe is an alcohol-based, biodegradable, and user-friendly fixative solution. The clinical specimens are well preserved and suitable for histopathology, genomics, and proteomics studies. The efficacy of instaPRESERVE Tissuesafe with ethanol or isopropyl alcohol and a modified tissue processing method without alcohol dehydration steps was studied. The pigs organs, brain, and liver tissues were fixed with NBF and InstaPRESERVE Tissuesafe solutions (ethanol/isopropyl alcohol). Based on the alcohol content of instaPRESERVE Tissuesafe, the dehydration step(s) were skipped during tissue processing. Serial sections from fixed tissues were processed and stained with H&E. The intactness of the sections with instaPRESERVE Tissuesafe fixation was comparable to that of NBF fixation. No autolysis/ decomposition was observed with InstaPRESERVE Tissuesafe (both) and NBF. The H&E staining scoring was satisfactory with well-preserved cell boundaries and organelles in both liver and brain tissue sections. The key factors of any fixative are its penetration, temperature, and time taken for fixation. In this study, the penetration rate of InstaPRESERVE Tissuesafe with either ethanol or isopropyl alcohol was the same as NBF within 6 to 12 hrs. The results indicated that increased concentration of alcohol in instaPRESERVE Tissuesafe did not affect the histology, and overall quality of the tissue sections processed was comparable to formalin fixation. The cytoplasmic and nuclear details, erythrocyte integrity, and lymphocytic appearance were well maintained. The time was reduced to 6 hrs from 9 hrs of the standard method. This study has addressed the modification of tissue processing with reduced time in histopathology with instaPRESERVE Tissuesafe. The outcome of this study has shown that instaPRESERVE Tissuesafe may be an alternative to formalin and helps in faster diagnosis.

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Vangala, R. K., Vangala, A. B., Kanukollu, S., Sankarnarayanan, P. M., Shankar, A., Murugaian, E. E.. 2025-05-08. STREAMLINING HISTOPATHOLOGY: INSTAPRESERVE TISSUESAFE A SINGLE-STEP FIXATIVE THAT IMPROVES TISSUE QUALITY AND WORKFLOW EFFICIENCY. https://doi.org/10.1101/2025.05.01.651707

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