Investigation into a new softening agent for use on formalin-fixed, paraffin wax-embedded tissue.

The use of tissue softening agents to improve microtomy of keratotic tissues is employed widely. Many of these softeners contain hazardous constituents such as phenol. In this study, the use of non-ionic surfactants or non-toxic ingredients are investigated with the aim of creating a new softening agent. The new agent should be more effective in facilitating the sectioning of hardened tissue while reducing toxicity and complications associated with sectioning hard tissue compared to a commercially available phenol-based formulation. Four formulations are compared against the commercial product for their capability to section routinely processed paraffin-embedded tissue under standard operating procedure parameters. The trial formulations were shown to be fast acting and enabled improved serial sectioning of hard keratotic tissue in nearly all the cases tested. There was no evidence of adverse staining using either tinctorial or immunohistochemical methods. The new formulations had advantages over the commercially available solutions, improving on the number and quality of sections attainable from the tissue blocks, as well as offering a composition less toxic than phenol-based products.