Transmission of SARS-CoV-2 – the causative agent of COVID-19 – can be prevented through   nonpharmaceutical interventions such as observing proper hand hygiene using   alcohol-based hand rubs/sanitisers (ABHRs) as recommended by the WHO and   local health authorities. However, this recommendation has led to high demand   for ABHRs and proliferation of sub-standard products, which do not contain   the recommended amount of alcohol. Fifty products of different origins and   formulations obtained off-the-shelf and in public places in and around   Pretoria (South Africa) were analysed for their alcohol content using gas   chromatography. Ethanol was the most common alcohol used in the products,   followed by isopropanol. Only 21 (42%) of the products analysed contained at   least 70% alcohol; of these only 14 (28%) met the WHO recommended 80±5% alcohol content to have a virucidal effect on SARS-CoV-2. Of the 41   commercial off-the-shelf products analysed, 27 (66%) contained less than 70%   alcohol in comparison to 13% of homemade products. Only 18% of gel products   contained 70% alcohol, compared with 47% for liquid-based products. Most of   the products did not contain the appropriate or correct declaration as   recommended by the South African National Standards (SANS 289 and 490). The   proliferation of substandard ABHRs is of great public health concern and   calls for stricter regulations and enforcement in order to protect consumers,   their rights and well-being during and post the COVID-19 pandemic period.   However, in the interim, formulation of ABHRs using the WHO guidelines should   be mandatory, as such formulations, when made correctly, do have the required virucidal effect against SARS-CoV-2.

Determination of alcohols in hand sanitisers: Are off-the-shelf hand sanitisers what they claim to be?

Alcohol-based hand sanitisers

Commercially available liquid- and gel-based ABHRs hereafter ‘off the shelf’ were   purchased from stores or sampled from hand sanitising points at public places (schools, offices, shopping malls, restaurants, places of worship) in and   around Pretoria, Gauteng Province, South Africa. Another set of ABHRs that were made based on WHO recommendations for hand rubs using locally available   ingredients at home by persons or in the laboratory for the daily use of   personnel (hereafter referred to as ‘homemade’) were solicited from and   provided by volunteers. The ABHRs were sampled directly from the container   (in the case of those purchased) or collected in 1.5-mL sterile Eppendorf   tubes. Overall, 50 ABHR products were analysed, of which 38 were liquids, 11   were gels and 1 was a spray-based formulation.

Gas  chromatographic analysis of alcohols in ABHRs

For   the analysis, a 6890 Agilent gas chromatograph fitted with a flame ionisation   detector and an Agilent HP-INNOWax polyethylene glycol (model number Agilent   19091N-102) column (25 m × 200 µm × 0.20 µm) was used. Samples were injected   in the split mode with a split ratio of 30:1 at 140 °C and a pressure of   24.14 psi. The temperature of the flame ionisation detector was set at 200   °C, the flow rates for hydrogen, air and nitrogen were set at 40, 150 and 25   mL/min, respectively, and that of the carrier gas helium was set at 1.4   mL/min. The oven was programmed as follows: 35 °C for 1 min, increased by 5 °   per min to 40 °C, held for 1 min ramped at 15 °C to 75 °C with a 1 min hold   and finally increased at 25 °C per min to 220 °C. To validate the method, a   mixture of seven alcohols containing methanol, ethanol, isopropanol,   pentanol, isobutanol, butanol and octanol was analysed. Thereafter, 1 µL of   each ABHR was analysed on the gas chromatograph and the alcohol content   quantified using an external calibration curve made up of either ethanol or   isopropanol (the two main alcohols recommended by the WHO for use in ABHRs)   in the range of 10–100% (v/v). The concentration of either ethanol or   isopropanol was determined using the equation of the trend line , The   equation of the trend line y=mx+c, where y = measured peak intensity of   alcohol, m = gradient, x = unknown concentration of alcohol and c =   intercept. As a reference and quality control standard check, a 91% ethanol   standard was analysed with each batch of samples. All samples were analysed   in duplicate and the composition of alcohols presented as mean proportions ±   standard errors. Comparisons between ABHR formulation types and sources were   made using a chi-square (X2 ) test of proportions using the Proc FREQ command   in the statistical software SAS version 9.4 (SAS Inc, USA).

Alcohol-based hand sanitisers & Gas chromatographic analysis of alcohols in ABHRs

Co-Founder of Sci Find–The scientific collaboration network.

COVID-19

Biology

Featured Guilds

Bioinformatics

CRISPR

Molecular Biology

Neuroscience

Synthetic Biology

Guild Members

Guy Rohkin

Have a question?