The Quantitative Analysis of Ethanol-based Hand Sanitizers and Prediction of Methanol Adulteration Using FTIR-ATR Technique

Background - In this paper, a spectroscopic method is used to quantify the methanol and ethanol together present in the hand sanitizers with the help of the FTIR-ATR spectrometer using the Beers law quant method. Objective - The aim of this study is to determine the content of methanol as an adulterant in the ethanol-based hand sanitizers which are commercially available in the local market of Hapur with the help of FTIR –ATR technique. Method - In order to find out the methanol, seven synthetic hand sanitizers of ethanol contaminated with methanol were prepared and three for cross-validation as per the formulation of WHO for hand sanitizers. The calibration curves were constructed using Beers law by finding the peak area in the range 1020-1022 cm -1 & 1044-1046 cm -1 for methanol and ethanol respectively using Quant software. The linear curves so obtained have shown the correlation coefficient 0.997 and 0.996 for methanol and ethanol respectively. Five branded ethanol-based hand sanitizers were analyzed by FTIR-ATR. Result- The analysis of the locally purchased hand sanitizers shows less content of ethanol than claimed in most of them. However, none of the brands shows the presence of methanol as an adulterant. The validity of the method can be verified by the three synthetic sanitizers which were adulterated by methanol. Conclusion - With the widespread of Covid-19 the presence of methanol in hand sanitizers cannot be ruled out which can be harmful to health. In this paper, we have used a technique that is fast, cost-effective, and accurate to evaluate the adulteration of methanol in hand sanitizers.