Through-container quantitative analysis of hand sanitizers using spatially offset Raman spectroscopy

Advancing ethanol content determination in hydrogels: non-destructive and operational methods for health and criminal inspections

The significance of accurate determination of ethanol content in hydrogel formulations was accentuated during COVID-19 pandemic coinciding with the heightened demand for sanitizing agents. The present article proposes three robust methodologies for this purpose: Fourier Transform Infrared Spectroscopy (FTIR), Raman spectroscopy, and Densitometry with matrix effect correction by Near-Infrared Spectroscopy (NIR). All three methods demonstrated outstanding linearity (R2 ≥ 0.99) and minimal errors (< 1.7%), offering simplicity and operational efficiency. FTIR and Raman, being non-destructive and requiring minimal preparation, enable practical on-site analysis capabilities, underscoring the potential of the spectroscopic methods to expedite health investigations and inspections, empowering on-site ethanol determination, and relieving the burden on official laboratories. Additionally, the densitometry with NIR-based approach showcased superior accuracy and precision compared to spectroscopic methods, meeting validation criteria while offering operational advantages over the costly official distillation-based method. Therefore, it stands as a reliable and reproducible technique for comprehensive health and criminal compliance assessments, making it a compelling alternative for both industry and official laboratories.

Quality of New Domestic Hand Sanitizer Drug Product Manufacturers During COVID-19

The FDA initiated a cross-sectional, statistically based sampling and testing study to characterize the quality of marketed alcohol-based hand sanitizer (ABHS) by evaluating the alcohol content and impurities present in ABHS products manufactured by establishments that registered with the FDA during March-April 2020. A stratified sampling design divided the population of manufacturers into independent groups based on each establishment's level of experience with FDA oversight and its geographic location. ABHS products were collected and analyzed by spatially offset Raman spectroscopy and gas chromatography with mass spectrometry (GC-MS). The GC-MS results for 310 products, from 196 newly registered domestic manufacturers, showed that 71.6% (± 5.7%) of these manufacturers had violative products. In 104 (33.5%) cases, the alcohol content did not meet label claim assay specifications but still fell within CDC efficacy ranges. Ethanol ABHS products failed more often overall (assay and impurities) (84.3%) and for impurities (84.3%), than isopropanol ABHS products (11.2% and 6.2%, respectively). Differences in test results across active ingredients were statistically significant. Ethanol ABHS products often (63.5% of cases) failed due to the presence of acetal or acetaldehyde, particularly in products with pH ≤ 6. Other impurities were also detected in several ABHS products, suggesting the use of low-grade alcohol in the manufacture of these products. Evidence was insufficient to conclude that having experience manufacturing FDA-regulated products, or lack thereof, influenced product-level violative results. This study highlights the importance of sourcing and testing active pharmaceutical ingredients to produce quality drug products.

Assessment of quality of commercial hand sanitizers using Fourier transform infrared spectroscopy and gas chromatography

Since the beginning of the COVID-19 pandemic, the use and manufacture of alcohol-based hand sanitizers increased exponentially. Efficacy of hand sanitizers mainly depends on active ingredients like ethanol and isopropanol (IPA). Even though methanol is extremely hazardous to people, it is still illegally used in hand sanitizers in Bangladesh. Developing a quick and simple analytical method for detecting and quantifying ethanol/IPA/methanol is crucial. Here, Fourier transform infrared spectroscopy (FTIR) was used to identify and quantify alcohol content in commercially available hand sanitizers in a quick and easy way. Comparing the FTIR and GC data, provided quite similar results. Unlike previous studies by FTIR, C-H, CH₃-C-CH₃ stretching, and C-H bending vibrational modes were employed to construct analytical calibration curves to detect and quantify alcohol in hand sanitizers. According to FTIR and GC findings, ethanol and IPA content were found to be 43-82% and 40-69%, and 56-64% and 61-66%, respectively, whereas ethanol was labeled at 66-80% and IPA at 65-70%. FTIR and GC revealed methanol content ranging from 37 to 98 and 19 to 81%, respectively. Also, the FTIR was significantly faster than the GC. Therefore, FTIR can be used to commercially analyze the quality of hand sanitizers.•FTIR was used to identify and quantify alcohol content in commercially available hand sanitizers in a quick and easy way.•Comparing the FTIR and GC data, provided quite similar results.•Out of ten samples, five contained ethanol, three IPA, and two methanol.

Alcohol-based Hand Sanitizers amid COVID-19: Chemical Formulation, Analysis, Safety

Alcohol-based hand sanitizers (ABHSs) containing ethanol (EtOH) or isopropyl alcohol (IPA) to inactivate microorganisms help prevent the spread of respiratory diseases. These products have become very popular during the COVID-19 pandemic. Apart from vaccines or other preventative antiseptic measures, the majority of consumers have relied on different types of ABHSs to disinfect their hands. As a result, there has been a global rush in the demand for these ABHSs and other antiseptic hygiene products. This has resulted in the formation of many new commercial sanitizer producers. There are around fifty companies of varying sizes that have been marketing their ABHSs in Bangladesh, most of which have only been manufacturing their products for the first time since the COVID-19 pandemic. To monitor the quality and components of these products, the Bangladesh Council of Scientific and Industrial Research (BCSIR) analyzed approximately 200 different hand sanitizer samples using GC-FID method. All samples were alcohol-based except for 3 which were alcohol-free aqueous hand sanitizers. Of the supplied formulated ABHSs, 80 samples were found to contain only IPA and 54 contained only EtOH. However, 28 samples were found to be contaminated with methanol (MeOH), 7 samples contained only MeOH and 18 samples contained both EtOH and IPA. This is the first study to explore the analysis of alcohol content in formulated ABHSs and their marketing status in Bangladesh, but the findings could be of use in other jurisdictions as similar issues have been raised in many parts of the world.

Application of a headspace GC-MS method to evaluate the product quality of alcohol-based wipe hand sanitizers (ABHS)

The investigation of marketed wipe hand sanitizers presented an analytical challenge due to the extraction from the solid matrix of the products. The present work describes the development of a new sample preparation method for the extraction of analytes from wipe hand sanitizer matrix into dimethyl sulfoxide for analysis by headspace GCMS. ABHS wipe products labeled to contain ethanol or isopropanol as active ingredients were tested, varying in the size and weight of the wipes. The spike recovery assay was confirmed using spiking solutions containing the impurities at concentrations equivalent to 50%, 100% and 200% of the interim concentration limits. All tested analytes showed recovery within the allowable limits (80%-120%). Six marketed ABHS wipe products were tested and no impurities above the FDA interim limits were observed. One product contained ethanol below the 60% v/v limit and another product was mislabeled for isopropanol and was found to contain ethanol instead. Four of the six ABHS products did not meet the label claim, which may affect the product quality. The analytical method and sample preparation procedures will provide the FDA and ABHS manufacturers with the capability to conduct quality assurance testing of wipe hand sanitizers for active ingredient content and impurities.

Development and validation of a headspace GC-MS method to evaluate the interconversion of impurities and the product quality of liquid hand sanitizers

The COVID-19 pandemic has led to increased usage of hand sanitizer products by the public to prevent the spread of COVID-19 and decrease the likelihood of acquiring the disease. The increase in demand has also led to an increase in the number of manufacturers. This work describes the FDA's Center for Drug Evaluation and Research (CDER) laboratories efforts to develop tests to assess the quality of hand sanitizer products containing ethanol or isopropanol as the primary active ingredient. The products were evaluated for the active ingredient content and determination of the 12 impurities listed in the FDA Hand Sanitizer Temporary Guidance, followed by a spike recovery assay performed to verify the test results. Extensive method development was conducted including an investigation into the stability of ethanol, isopropanol, and the 12 impurities. Stability and kinetic studies confirmed the instability of acetal in acidic liquid hand sanitizer products during spike recovery assay testing. The headspace GC-MS method was validated according to ICH Q2 (R1) guidelines and the spike recovery assay was validated using three concentrations of standards for the drug product. During method application, six liquid hand sanitizer products were tested and all were determined to have ethanol or isopropanol above 70% v/v. Two liquid hand sanitizer products were determined to contain acetaldehyde as an impurity above the FDA recommended safety levels.

SUPPLEMENTARY INFORMATION

The online version contains supplementary material available at 10.1186/s41120-021-00049-8.