The aim of our study was to evaluate the efficacy of n-Heptane (C7H16) as a xylene substitute for clearing, deparaffinizing and staining procedures in routine histopathology. 30 biopsied oral tissues were divided in two halves, each half was processed by xylene and n-Heptane respectively.
To substitute toxic aromatic solvents with nonhazardous aliphatic derivatives.
The second part of the study was conducted with the objective to reduce the concentration of comparatively expensive n-Heptane.
A sample size of 20 was considered for immunohistochemistry (IHC), with Cytokeratin and Vimentin as epithelial and connective tissue markers respectively.
Kappa statistical analysis established agreement between observers in all criteria's with significant p value < 0.05. The p value (> 0.05) was not statistically significant with Mann-Whitney U Test, for all criteria's indicating comparable results between n-Heptane and xylene. The clarity, uniformity, crispness, section quality as well as cellular parameters of nuclear & cytoplasmic staining, nuclear cytoplasmic contrast, cell morphology were found comparable between n-Heptane and xylene.
n-Heptane is not as hazardous and toxic as aromatic or chlorinated solvents. Thus it can be considered as a convenient substitute to xylene.