Orapuh Journal | Journal of Oral & Public Health
Development of a ‘drop-count’ method for the screening of the ethanol content in hand sanitisers using oxalic acid and potassium permanganate titrimetry
Orap J Vol 3 Issue 1 2022


hand sanitiser
oxalic acid
potassium permanganate

How to Cite

Monts’o, K. E., Ts’emane , R., Mpakanyane , T. E., Masiloane-Bohloko, S. C., Ramashamole , T. V., & George, M. (2022). Development of a ‘drop-count’ method for the screening of the ethanol content in hand sanitisers using oxalic acid and potassium permanganate titrimetry. Orapuh Journal, 3(1), e901. https://doi.org/10.4314/orapj.v3i1.1


The demand for ethanol-based sanitisers has increased dramatically since the dawn of the COVID-19 era, making it very difficult for health regulators to ensure the quality of the products and the safety of unsuspecting consumers. This article reports the development and application of a simple 'drop-count' titrimetry method for the determination of ethanol in hand sanitisers.
Materials and Methods
This method follows the classical potassium permanganate-oxalic acid titrimetry but uses very small volumes of the reagents – 0.5 mL of ethanol sample solution, 6 mL of acidified 0.1 M potassium permanganate, and a few counted drops of 0.1M oxalic acid.
This method achieved satisfactory figures of merit, namely, linearity (R2 ≥ 0.9667), reproducibility, and importantly very little matrix effect in the alcohol concentration range of 50 to 80%.
The small volumes (< 10 mL in total) of the reagents required make this method considerably safe and cost-effective and applicable for fieldwork even by untrained personnel, not just chemists as is often the case for field applications.



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