Comparative study of the dewaxing and clearing effect of isopropyl alcohol and xylene in histopathological staining

Dewaxing and clearing are essential steps in histological staining that impact morphology and staining quality. Xylene, a synthetic product, is a conventional agent in achieving these processes, but has toxicity and environmental concerns. This study compares the efficacy of isopropyl alcohol (IPA), an alternative and less toxic product, and xylene as dewaxing and clearing agents in histopathological staining of paraffin-embedded liver and kidney tissues. Eight paraffin-embedded tissue blocks were used, four of which were liver samples and the other four kidney samples. The control group was dewaxed in two changes of xylene for 5 minutes each. The test group was divided into three subgroups and was dewaxed in two changes of IPA for 5, 10, and 15 minutes, r e s p e c t i v e l y. A l l s a m p l e s u n d e r w e n t haematoxylin and eosin (H&E) staining. After staining and before mounting, the control group was cleared in two changes of xylene for 5 minutes each, while the test group was cleared in two changes of IPA for five minutes each. Photomicrographs were taken at 100x magnification and assessed qualitatively and quantitatively for proper dewaxing, clearing and staining clarity. Xylene scored 4/4, indicating excellent staining. IPA at 10 minutes scored 2/4 (poor), but IPA at 20 and 30 minutes scored 4/4, comparable to xylene. In conclusion, IPA used for 20–30 minutes is an effective and safer alternative to xylene for dewaxing and clearing in histopathology.