Developing a novel formulation for gel hand sanitisers using hypochlorous acid

Funding for the project was secured from the University of Edinburgh’s EPSRC Impact Acceleration Account as a part of the Rapid Response initiative to tackle challenges arising due to the COVID-19 pandemic. ECFP first carried out a literature review to determine which gelling agents would be worthwhile testing. From here, protocols were developed to formulate HOCl-based sanitiser samples to test in the lab using 10 different gelling agents.

ECFP performed steady shear rheology measurements to determine the flow behaviour of the gels. Understanding and characterising this behaviour is key to developing a final product that can be bottled and transported but retain a suitable viscosity and drying time upon application. The stability of the gel formulations, both chemically and physically, was also assessed over a period of days to months.

Cryo-FIB-SEM was used to examine the gels’ surface structure (below) and polymer networks. Finally, colleagues at the Roslin Institute carried out virucidal experiments using influenza and herpes viruses. These determined the minimum concentration of HOCl needed in a formulation to retain effective biocide properties.

The knowledge gained during the project helped guide Aqualution to a suitable gelling agent for their formulation. This has enabled the company to launch a new product to market: Salvesan Skin, the first gel hand sanitiser produced using hypochlorous acid.

The hand gel is also approved in the UK for use as a hand sanitiser by the Health and Safety Executive (HSE) and gained Article 55 derogation for use as a PT1 hand sanitiser, being the only hypochlorous based hand sanitiser authorised to be sold in the UK. The product is also Halal-certified.

Salvesan Skin hand gel has been used by the NHS for booster vaccinations clinics where it is at the forefront of keeping patients safe in Wiltshire via the Sarum Cathedral Primary Care Network, made up of Harcourt Medical Centre and Salisbury Medical Practice. The Network dispensed Salvesan Skin via Gelpoles to over 25,000 patients in October and November who were attending the clinic for their Covid-19 boosters.

Recognising that Salvesan’s HOCl-based gel innovation is spearheading a revolution in infection control, the product has won Aqualution a national prestigious award at the Business Insider Made In Scotland awards, for Best New Product. This award is for a new product designed and/or manufactured in Scotland and put on the market from November 2020 to December 2021 which has the potential to drive significant new sales. The award ceremony was held on Thursday 19th May 2022 at the Glasgow Science Centre, sponsored by Scottish Business Insider and the National Manufacturing Institute of Scotland.