Analysis of Alcohol Levels in Hand Sanitizer

Importance of the Topic

The accurate measurement of alcohol levels in hand sanitizers is essential for ensuring product efficacy, safety, and regulatory compliance. During the COVID-19 pandemic, demand for alcohol-based sanitizers rose sharply, leading authorities such as the US FDA, CDC, and WHO to define minimum alcohol content requirements. Routine verification guards against dilution, contamination, and fraudulent products, protecting public health.

Aims and Study Overview

This study presents a rapid, reliable method for quantifying ethanol and isopropyl alcohol in hand sanitizer formulations using Agilent FTIR instrumentation. It demonstrates method development, calibration, sample analysis, and pass/fail evaluation in both laboratory and field settings.

Methodology and Instrumentation

The method employs attenuated total reflection FTIR spectroscopy based on Beer’s law. Calibration standards of ethanol and isopropyl alcohol were prepared in glycerol, hydrogen peroxide, and water. Key spectral features in the fingerprint region (880 cm-1 for ethanol and 950 cm-1 for isopropyl alcohol) were used for identification, while the C-O stretch band (1000–1120 cm-1) supported quantitation.

• Agilent Cary 630 FTIR with ATR accessory for laboratory analysis
• Agilent 4500 Portable FTIR for on-site, battery-powered measurements
• Agilent MicroLab software for guided workflows, calibration, and color-coded results

Main Results and Discussion

Calibration and method setup require less than 15 minutes. Sample analysis, including data acquisition and pass/fail assessment, takes under one minute per sample. Measured concentrations for test samples closely matched target values, with deviations within ±1.9% and well under the WHO tolerance of ±5%. A threshold of 60% alcohol content was applied, displaying results in red or green to indicate compliance.

Practical Benefits and Applications

The FTIR method offers:

• Rapid identification of alcohol type and concentration
• Minimal sample preparation and reagent usage
• Portable and flexible deployment at production sites or delivery points
• Automated pass/fail reporting to support quality control workflows

Future Trends and Opportunities

Advancements may include expanded multicomponent analysis for additives such as fragrances and antimicrobials, integration with cloud-based data management, and AI-driven spectral interpretation. Portable FTIR platforms will continue to support decentralized quality assurance in supply chains and regulatory inspections.

Conclusion

The Agilent FTIR approach provides a fast, accurate, and user-friendly solution for verifying alcohol content in hand sanitizers. Its simplicity, portability, and compliance with international guidelines make it an effective tool for manufacturers, regulators, and quality control teams.

Reference

1. WHO Guide to Local Production: WHO-recommended Handrub Formulations, 2010.
2. CDC Show Me the Science: Hand Sanitizer Effectiveness, accessed June 2020.
3. FDA Temporary Policy for Preparation of Alcohol-Based Hand Sanitizer, June 2020.