Skin- and Eco-Friendly Hand Sanitizer: A Novel Composition of Natural Extracts to Prevent the Spread of Respiratory Viruses.

Respiratory diseases caused by viruses are a serious global health threat. Although the use of hand sanitizers containing alcohol and synthetic antiseptic agents is recognized as an effective, simple, and low-cost measure to combat viral transmission, they can harm human health and the environment. Thus, this work aimed to study the efficacy of combining Camellia sinensis and Chamomilla recutita extracts in a skin- and eco-friendly leave-on hand sanitizer to prevent the spread of respiratory viruses. An oil-in-water emulsion containing C. recutita oily extract (5.0%), C. recutita glycolic extract (0.2%) and C. sinensis glycolic extract (5.0%) showed virucidal activity against HAdV-2 (respiratory virus) and two surrogate viruses of SARS-CoV-2 (HSV-1 and MVH-3), showing great potential to prevent the spread of respiratory viruses. These natural extracts combined are also promising to combat a broad spectrum of other viruses, in the form of antiseptic mouthwashes or throat sprays, surface disinfectants, and veterinary products, among others. Complementally, the developed hand sanitizer demonstrated efficacy against bacteria and fungus.

SmartAnalysis: A sustainable digital-image colorimetry method for ethanol determination in alcohol-based hand sanitizer / SmartAnalysis: Un método sostenible de colorimetría de imagen digital para la determinación de etanol en desinfectante de manos a base de alcohol

Introducción: El consumo de desinfectantes de manos a base de alcohol ha aumentado significativamente después de la pandemia causada por el SARS-CoV-2. A pesar de la conclusión de la emergencia sanitaria declarada por la OMS en 2023, la costumbre de desinfectar las manos con geles sanitizantes a base de etanol ha sido adoptada a nivel mundial por la población. Dado que los métodos generales descritos en los compendios oficiales para la de-terminación del etanol, como la cromatografía de gases o la destilación, son laboriosos y no específicos para geles que contienen carbómero, este trabajo propone un método alternativo basado em la colorimetría de imágenes digitales. Método: La imagen digital (proporcionada por la reacción etanol-fenolftaleína) fue capturada y transformada en una señal analítica basada en el sistema de colores Rojo-Verde-Azul. Las adquisiciones de imágenes se realizaron utilizando un smartphone Samsung Galaxy J6, y las señales se generaron mediante el programa gratuito Photometrix Pro®. El método fue validado de acuerdo con las directrices de la ICH y se aplicó en muestras comerciales. Además, el método propuesto fue evaluado por su impacto ambiental utilizando la herramienta Índice del Proceso Analítico Verde (GAPI). Se generaron pictogramas utilizando el programa gratuito ComplexGAPI®.Resultados: El canal verde mostró una respuesta lineal en las curvas de calibración para concentraciones de etanol que van desde el 5 hasta el 40 % (p/p) en medio ácido. El método demostró linearidad, precisión, exactitud y robustez. Conclusiones: El método propuesto presentó como principales ventajas el uso de dispositivos de bajo costo y fáciles de manejar, así como un consumo reducido de reactivos, de acuerdo con los principios de la química analítica verde. (AU)

Introduction: The consumption of alcohol-based hand sanitizers has increased significantly after the pandemic caused by SARS-CoV-2. Despite the conclusion of the health emergency declared by the WHO in 2023, the habit of sanitizing hands with ethanol-based gel sanitizers has been globally adopted by the population. Since general methods described in official compendia for ethanol determination such as gas chromatography or distillation are laborious and not-specific to carbomer-containing gels, this work proposes an alternative method based on digital image colorimetry. Method: The digital image (provided by ethanol-phenolphthalein reaction) was captured and transformed into an analytical signal based on the Red-Green-Blue system. The image acquisitions were performed using a Samsung Galaxy J6 smartphone, and the signals were generated using the Photometrix Pro® free program. The method was validated in accordance with ICH and applied in commercial samples. Additionally, the proposed method was eval-uated for its environmental impact using the Green Analytical Process Index (GAPI) tool. Pictograms were generated using the ComplexGAPI® free program. Results: Green channel exhibited a linear response in the calibration curves for ethanol concentrations ranging from 5 to 40 % (w/w) in acidic medium. The method showed linearity, precision, accuracy, and robustness. Conclusions: The proposed method presented as main advantages the use of low-cost and easy-to-handle devices and reduced reagent consumption, in accordance with green analytical chemistry principles. (AU)

Purification and use of crude green glycerol from the transesterification of triglycerides in the formulation of an alcohol gel hand sanitizer.

The aim of this study was to produce an alcohol gel hand sanitizer containing green glycerol. Crude glycerol was purified using chemical and physical treatments. The sanitizer was prepared using 71.100 g of 99.3° GL ethanol, 28.0 g H2O, 0.5 g of Carboxypolymethylene [Carbopol 940® or Carbomer], 5 drops of triethanolamine (pH 5-7), and glycerol (1.5% w/w). The thermal behavior of the ethanol, carbopol, triethanolamine, glycerol, and alcohol gels were evaluated using Thermogravimetry and Differential Thermal Analysis. The apparent viscosity was obtained using a rotary viscometer. The determination of in vitro spreadability was achieved by an adaptation of the Knorst method. The ethanol content was measured by headspace gas chromatography using a flame ionization detector. The thermal behavior of the gels was influenced by the presence of glycerol, which confirms the possible network interactions formed. The relative densities of the samples were between 0.887 and 0.890 g/cm3. No alteration of the pH of the formulation resulted from the incorporation of glycerol. The apparent viscosities of the alcohol gels were greater than 20,000 cP. No alteration in the in vitro spreadability of the gel alcohol (530.6 mm2) resulted from the addition of glycerol. Hand sanitizer was produced using glycerol from a transesterification reaction. It represents an alternative use for the glycerol being produced in biodiesel processes. The product satisfied the requirements of WHO that preconize a formulation containing 1.45% glycerol as an humectant to protect skin against dryness and dermatitis.

Hand hygiene compliance in nursing home wards: the effect of increased accessibility of alcohol-based hand rub.

BACKGROUND: Elderly nursing home residents are vulnerable to infection from micro-organisms. Hand hygiene is considered one of the most important measures to prevent transmission. AIM: To determine the effect of increased accessibility to alcohol-based hand rub (ABHR) in nursing home wards by monitoring hand hygiene compliance (HHC) among healthcare workers (HCWs). METHODS: An 11-month intervention study was conducted in a Danish six-ward nursing home. Data were collected using an automatic hand hygiene monitoring system (AHHMS). After a baseline period, one extra ABHR dispenser was placed in each of the 150 apartments. Baseline HHC was compared with the HHC during an immediate intervention period and a long-term intervention period. FINDINGS: A total of 159 HCWs were included. The AHHMS registered 341,078 hand hygiene opportunities. Overall baseline HHC was 31% (95% confidence interval: 30-32). A significant +18% absolute immediate effect (first five months) (95% CI: 17-19; P < 0.0001) and +13 percentage points (95% CI: 11-14; P < 0.0001) long-term effect (another four months) were recorded. HCWs working day shifts and short-term employees had a higher baseline HHC than HCWs working evening/night shifts. However, HCWs working night shifts achieved the greatest long-term effect with a mean +27 percentage point difference (P < 0.0001). CONCLUSION: Placing an additional ABHR dispenser strategically within staff workflow significantly increased HHC among HCWs, demonstrating a noteworthy effect. The study is the first to report the effect on nursing home dispenser accessibility as a single intervention and to show a significant unmet potential.

Development of spray-dried powder hand sanitiser with prolonged effectivity.

Since the outbreak of the COVID-19 pandemic, the use of hand sanitisers has become an inseparable part of our personal hygiene. However, the short-term effect and the need for frequent application are shortcomings that impair the overall protection. Another aspect is that repeated use of some products (typically alcohol-based) may cause skin irritation or eventually more severe health problems. This work proposes spray-drying as a suitable method for the preparation of swellable chitosan carriers, allowing for encapsulation and sustained release of antibacterial chlorhexidine digluconate as a model active substance. After application to hands, micron-sized particles preferentially accommodate space between epidermal ridges, protected against attrition. Thanks to their small size (d < 10 µm), particles are comfortable to carry since they are not recognisable by somatosensory receptors. The performance of formulations with various amounts of chlorhexidine and cross-linker was tested and compared with selected commercial disinfectants available on the Czech market (ethanol gel and alcoholic solution with chlorhexidine) against E. coli and S. epidermidis. The real-life performance was investigated with twelve volunteers performing various activities for up to 2 h. Finally, a replica of the human index finger with accurately captured micro-topology was proposed and compared with volunteers' fingers concerning the total amount of adhered and detached particles.

Transmission of Viruses from Restroom Use: A Quantitative Microbial Risk Assessment.

Restroom use has been implicated in a number of viral outbreaks. In this study, we apply quantitative microbial risk assessment to quantify the risk of viral transmission by contaminated restroom fomites. We estimate risk from high-touch fomite surfaces (entrance/exit door, toilet seat) for three viruses of interest (SARS-CoV-2, adenovirus, norovirus) through eight exposure scenarios involving differing user behaviors, and the use of hand sanitizer following each scenario. We assessed the impacts of several sequences of fomite contacts in the restroom, reflecting the variability of human behavior, on infection risks for these viruses. Touching of the toilet seat was assumed to model adjustment of the seat (open vs. closed), a common touch point in single-user restrooms (home, small business, hospital). A Monte Carlo simulation was conducted for each exposure scenario (10,000 simulations each). Norovirus resulted in the highest probability of infection for all exposure scenarios with fomite surfaces. Post-restroom automatic-dispensing hand sanitizer use reduced the probability of infection for each virus by up to 99.75%. Handwashing within the restroom, an important risk-reduction intervention, was not found to be as effective as use of a non-touch hand sanitizer dispenser for reducing risk to near or below 1/1,000,000, a commonly used risk threshold for comparison.

The impact of alcohol hand sanitizer use on skin health between healthcare worker: Cross-sectional study.

BACKGROUND: 2020 Coronavirus disease 2019 (COVID-19) has become a global health crisis, so hand alcohol-based sanitizers have become essential to preventive measures. Previous studies reported that hand sanitizers could kill bacteria and viruses; however, using them excessively can lead to health problems if misused. In light of sanitizer overuse, the availability of various products and qualities in the market, and the absence of data on skin problems, we conducted a survey study about the impact of commonly used sanitizers on skin health, particularly on hands. The study aimed to determine the prevalence and the correlation between hand sanitizer and skin health during the COVID-19 pandemic at the National Guard Institute- Jeddah, Saudi Arabia. METHODS: A cross-sectional study was conducted using a self-administered online questionnaire by sending an invitation link to students and employees of the National Guard Institute- Jeddah, Saudi Arabia, in 2021. A chi-squared test was used to obtain differences concerning awareness of hand sanitizer use/type and hand skin health. RESULTS: In the total 216 participants, there were considerably more skin conditions reported by women (62.5%) and respondents ages 31-40 (36.6%). For the types of hand sanitizers, 89.8%, 40.9%, 30.2%, 4.7%, and 6% were recorded: gel, spray, wipes, foam, and others, respectively, and the survey applicants were filled by 60.6% of non-medical workers. According to the survey, 32.9% of participants experienced a hand crack, which was the most common hand side effect. The handwashing frequency was reported between 3 to 7 times per day during the COVID-19 pandemic, and 9.3% of participants used hand sanitizers more than 10 times daily. CONCLUSION: It was found that during the pandemic, skin changes were common among the NGHA population and healthcare workers. Consequently, the adverse health effects of these hand sanitizers on human health may result in multiple infections and toxicity. The present study provides appropriate knowledge on the types and ingredients of hand sanitizers as essential factors for skin health, preventing health risks during this pandemic.

Determination and Quantification of Acetaldehyde, Acetone, and Methanol in Hand Sanitizers Using Headspace GC/MS: Effect of Storage Time and Temperature.

Accurate determination of the concentration of alcohols and their metabolites is important in forensics and in several life science areas. A new headspace gas chromatography-mass spectrometry method has been developed to quantify alcohols and their oxidative products using isotope-labeled internal standards. The limit of detection (LOD) of the analytes in the developed method was 0.211 µg/mL for methanol, 0.158 µg/mL for ethanol, 0.157 µg/mL for isopropanol, 0.010 µg/mL for n-propanol, 0.157 µg/mL for acetone, and 0.209 µg/mL for acetaldehyde. The precision and accuracy of the method were evaluated, and the relative standard deviation percentages were found to be less than 3%. This work demonstrates the application of this method, specifically in quantifying the concentration of oxidative products of alcohol and other minor alcohols found in hand sanitizers, which have become an essential household item since the COVID-19 pandemic. Apart from the major components, the minor alcohols found in hand sanitizers include methanol, isopropanol, and n-propanol. The concentration range of these minor alcohols found in ethanol-based hand sanitizer samples was as follows: methanol, 0.000921-0.0151 mg/mL; isopropanol, 0.454-13.8 mg/mL; and n-propanol, 0.00474-0.152 mg/mL. In ethanol-based hand sanitizers, a significant amount of acetaldehyde (0.00623-0.231 mg/mL) was observed as an oxidation product, while in the isopropanol-based hand sanitizer, acetone (0.697 mg/mL) was observed as an oxidation product. The concentration of acetaldehyde in ethanol-based hand sanitizers significantly increased with storage time and temperature, whereas no such increase in acetone concentration was observed in isopropanol-based hand sanitizers with storage time and temperature. In two of the selected hand sanitizers, the acetaldehyde levels increased by almost 200% within a week when stored at room temperature. Additionally, exposing the hand sanitizers to a temperature of 45 °C for 24 h resulted in a 100% increase in acetaldehyde concentration. On the contrary, the acetone level remained constant upon the change in storage time and temperature.

Quality and safety of South African hand sanitisers during the COVID-19 pandemic.

Health agencies recommend using hand sanitisers as protection against the coronavirus. Thus far, the emphasis on hand sanitiser studies is limited to an analysis of disinfectant content only. This study aims to provide an extended analysis of 60 off-the-shelf alcohol-based hand sanitisers by using gas chromatography to report on alcohol content and the presence of impurities, a recombinant yeast estrogen screen to assess estrogenic activity, and an investigation into labelling compliance with the South African National Standard. Fifty hand sanitisers had an alcohol content of ≥60% v/v alcohol; however, most contained skin irritants and substances that could harm human and environmental health. Estrogenic activity was detected in 29 hand sanitisers and none of the products complied with all the labelling requirements. Since off-the-shelf hand sanitisers in South Africa are not regulated and monitored, evidence-based public awareness programmes on hand sanitiser quality and safety should become a priority.

A comparative study on the effect of alcohol-based hand sanitizers in spray and gel formulation on the skin: A prospective, randomised, crossover trial.

BACKGROUND: Many formulations of Alcohol-based hand rubs (ABHRs), such as liquid, gel, and spray have been developed and used for preventing infections. This study aimed to compare skin irritation from using ABHRs in gel and spray formulations. METHOD: This was a prospective, randomised, crossover trial conducted to investigate the effect of skin irritation caused by ABHRs in gel compared to spray formulation after 21 days of using each formulation. Clinical outcomes were assessed using subjective Larson's skin assessment score and Frosch and Kligman observer skin assessment score, as well as bioengineering measures: transepidermal water loss (TEWL) and skin capacitance on days 3, 7, 14, and 21. RESULTS: Among 38 participants, both formulations showed no significant change in clinical scores and skin capacitance during the study. However, TEWL increased significantly from baseline on day 3 (p = 0.029) for the spray formulation and on day 21 (p = 0.019) for the gel formulation, with no statistically significant difference between the formulations (p = 0.46). CONCLUSION: Our research supports the safety of gel and spray ABHRs for regular use, with the only potential issue being mild skin irritation. For those with sensitive skin, the gel formulation is preferable.

Availability of Hand Sanitizers in Food Establishments of New York City: An Observational Study.

Hand hygiene is a crucial tool to limit the transmission of common respiratory and gastrointestinal infections. While hand sanitizers were ubiquitous early in the COVID-19 pandemic, the number of food establishments that have adequately maintained them remains unknown. Through systematic observations in 89 New York City food establishments, we found that hand sanitizer dispensers were present in only 40% of the stores, and only 23% had functional ones. This scarcity highlights the necessity of providing ongoing support to small business owners nationwide to promote and maintain primary prevention measures at all times, extending beyond periods of public health crises.

Effectiveness of plant-based hand sanitizer incorporating Quercus infectoria gall extract.

AIMS: Quercus infectoria (Qi), a traditional herbal plant with a broad spectrum of activities on multidrug-resistant bacteria, has been developed for hand sanitizer applications. METHODS AND RESULTS: Antimicrobial activity was evaluated using agar-well diffusion and broth microdilution method. Bactericidal activity was determined following the European Standard 1276 antibacterial suspension test. Neutralization assay was performed to assess antirespiratory syncytial virus. Safety, stability, and skin permeation of Qi hand gel was investigated. Qi hand sanitizer gel inhibited microorganisms ranging from 99.9% to 99.999% against Enterococcus faecalis, Staphylococcus aureus, methicillin-resistant Staph. aureus, Staph. epidermidis, Staph. pseudintermedius, Staph. saprophyticus, Streptococcus pyogenes, Acinetobacter baumannii, Escherichia coli, Klebsiella pneumoniae, Pseudomonas aeruginosa, and Candida albicans. A significant reduction in main human dermatophytes including Microsporum canis, M. gypseum, and Talaromyces marneffei of ∼50% was observed (P < .05). Qi hand sanitizer gel inactivated >99% viral particles entering human laryngeal epidermoid carcinoma cells in a dose-dependent manner. Scanning electron micrographs further illustrated that Qi hand sanitizer gel disrupted microbial cell membrane after 1-min contact time resulting in cell death. Qi hand sanitizer gel delivered emollient compounds through simulated human skin layers and showed no cytotoxicity on fibroblast cells. Moreover, Qi hand sanitizer gel demonstrated stability under extreme conditions. CONCLUSIONS: Qi hand sanitizer gel was able to inhibit various microorganisms including bacteria, dermatophytes, and virus.

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.

Toxicity of chemical-based hand sanitizers on children and the development of natural alternatives: a computational approach.

The unintended exposure of children to hand sanitizers poses a high risk of potentially fatal complications. Skin irritation, dryness, cracking, peeling, hypoglycemia, apnea, and acidosis are examples of unintended consequences of hand sanitizer. The sanitizer reportedly kills normal microbial flora on hands, which usually promotes innate immunity among children under 12. Children are more susceptible to the toxicity associated with the chemical constituents of marketed chemical-based hand sanitizers; however, the studies to develop sanitizer formulations for children are rudimentary. The adverse events limit the use of hand sanitizers specifically in children because of their sensitive and delicate skin. Additionally, it is reported that many chemical-based hand sanitizer formulations, especially alcohol-based ones may also contain contaminants like methanol, acetaldehyde, benzene, isopropanol, and ethyl-acetate. These contaminants are found to be hazardous to human health exhibiting toxicity on ingestion, inhalation, or dermal exposure, especially in children. Therefore, it is important to design novel, innovative, safer sanitizer formulations for children. The study aims to discuss the toxic contaminants in chemical-based sanitizer formulations and propose a design for novel herbal formulations with minimal toxicity and adverse effects, especially for children. The review focuses on ADMET analysis of the common contaminants in hand sanitizers, molecular docking, Lipinski's rule of five analysis, and molecular simulation studies to analyze the efficacy of interaction with the receptor leading to anti-microbial activity and drug-likeness of the compound. The in silico methods can effectively validate the potential efficacy of novel formulations of hand sanitizers designed for children as an efficient alternative to chemical-based sanitizers with greater efficacy and the absence of toxic contaminants.

Current issues in hand hygiene.

BACKGROUND: Multiple aspects of hand hygiene have changed in recent years. METHODS: A PubMed search was conducted to identify recent articles about hand hygiene. RESULTS: The COVID-19 pandemic caused temporary changes in hand hygiene compliance rates and shortages of alcohol-based hand sanitizers (ABHSs), and in marketing of some products that were ineffective or unsafe. Fortunately, ABHSs are effective against SARS-CoV-2 and other emerging pathogens including Candida auris and mpox. Proper placement, maintenance, and design of ABHS dispensers have gained additional attention. Current evidence suggests that if an adequate volume of ABHS has been applied to hands, personnel must rub their hands together for at least 15 seconds before hands feel dry (dry time), which is the primary driver of antimicrobial efficacy. Accordingly, practical methods of monitoring hand hygiene technique are needed. Direct observation of hand hygiene compliance remains a challenge in many healthcare facilities, generating increased interest in automated hand hygiene monitoring systems (AHHMSs). However, several barriers have hindered widespread adoption of AHHMSs. AHHMSs must be implemented as part of a multimodal improvement program to successfully improve hand hygiene performance rates. CONCLUSIONS: Remaining gaps in our understanding of hand hygiene warrant continued research into factors impacting hand hygiene practices.

Outcomes of pediatric ingestions of alcohol-based hand sanitizers during the COVID-19 pandemic.

INTRODUCTION: In July 2020, an outbreak of methanol-contaminated hand sanitizers in the United States prompted our regional poison center to implement a more conservative triage guideline for hand sanitizer exposures. All pediatric hand sanitizer ingestions of more than a "taste" were referred to a healthcare facility for assessment. We then evaluated the effect of this change on identifying patients with methanol poisoning. METHODS: This was a single-center, retrospective review of pediatric (<19 years) hand sanitizer ingestions reported to our poison center from May 1, 2020 through January 28, 2022. Methanol and ethanol concentrations were collected if available. RESULTS: During the study period, we received 801 calls regarding hand sanitizer exposure, of which 140 children were referred to a healthcare facility for hand sanitizer ingestions. Of those, 88 (63%) had methanol and/or ethanol concentrations measured. No child had a detectable methanol concentration, 78 had ethanol testing, and 12 had a detectable ethanol concentration. CONCLUSIONS: In this sample, no patient tested had a detectable methanol concentration. Children who consumed enough to have a detectable ethanol concentration were symptomatic or had an intentional ingestion. Asymptomatic children with unintentional ingestion of hand sanitizer were at low risk for methanol toxicity.

Evaluating the antimicrobial efficacy of long-lasting hand sanitizers on skin.

BACKGROUND: The microbicidal efficacy of hand sanitizer formulations is usually measured through standardized quantitative suspension tests and fingerpad tests; these cannot evaluate long-lasting formulations or are impractical due to biological risks, high cost, or time required for testing. With increased numbers of long-lasting microbicidal activity claims of commercially available hand sanitizers, alternative testing strategies are required. AIM: To explore the use of a standardized ex-vivo pig skin model to reproducibly measure long-lasting efficacy of an alcohol-free hand sanitizer formulation. METHODS: The microbicidal efficacy of an alcohol-free hand sanitizer was tested against Staphylococcus aureus, Escherichia coli and Klebsiella pneumoniae, and the enveloped virus SARS-CoV-2 with quantitative suspension tests (EN13727 and EN14476) with a contact time of 5 min. The product was then tested over a 6 h period using an ex-vivo pig skin model with a modified version of PAS 2424 to simulate the impact of skin abrasion. FINDINGS: Quantitative suspension tests yielded a >5 log10 reduction for all organisms tested within a 5 min contact time. Pig skin tests showed reduced but consistent efficacy at all time points and indicated no significant impact of abrasion on efficacy. CONCLUSION: The use of the ex-vivo pig skin model provides a potentially viable and convenient model system to test long-lasting hand sanitizer formulations, providing a path for sustainable hand sanitizer formulation claims of activity on skin.

Development and efficacy assessment of hand sanitizers and polylactic acid films incorporating caffeic acid and vanillin for enhanced antiviral properties against HCoV-229E.

BACKGROUND: Although three years after the outbreak of SARS-CoV-2, the virus is still having a significant impact on human health and the global economy. Infection through respiratory droplets is the main transmission route, but the transmission of the virus by surface contact cannot be ignored. Hand sanitizers and antiviral films can be applied to control SARS-CoV-2, but sanitizers and films show drawbacks such as resistance of the virus against ethanol and environmental problems including the overuse of plastics. Therefore, this study suggested applying natural substrates to hand sanitizers and antiviral films made of biodegradable plastic (PLA). This approach is expected to provide advantages for the easy control of SARS-CoV-2 through the application of natural substances. METHODS: Antiviral disinfectants and films were manufactured by adding caffeic acid and vanillin to ethanol, isopropyl alcohol, benzalkonium chloride, and PLA. Antiviral efficacies were evaluated with slightly modified international standard testing methods EN 14,476 and ISO 21,702. RESULTS: In suspension, all the hand sanitizers evaluated in this study showed a reduction of more than 4 log within 2 min against HCoV-229E. After natural substances were added to the hand sanitizers, the time needed to reach the detection limit of the viral titer was shortened both in suspension and porcine skin. However, no difference in the time needed to reach the detection limit of the viral titer was observed in benzalkonium chloride. In the case of antiviral films, those made using both PLA and natural substances showed a 1 log reduction of HCoV-229E compared to the neat PLA film for all treatment groups. Furthermore, the influence of the organic load was evaluated according to the number of contacts of the antiviral products with porcine skin. Ten rubs on the skin resulted in slightly higher antiviral activity than 50 rubs. CONCLUSION: This study revealed that caffeic acid and vanillin can be effectively used to control HCoV-229E for hand sanitizers and antiviral films. In addition, it is recommended to remove organic matter from the skin for maintaining the antiviral activity of hand sanitizer and antiviral film as the antiviral activity decreased as the organic load increased in this study.

Exploitations of Schiff's test and iodoform test for an effective quality assessment of alcohol-based hand sanitizers.

In the period of the corona virus disease 2019 (COVID-19) outbreak, an alcohol-based hand sanitizer is one of the most in-demand products for disinfection purposes. Two major concerns are adulteration of methanol, which causes toxicity to human health, and the concentration of legal alcohol in hand sanitizers due to their effect on antivirus. In this work, the first report of the entire quality assessment of alcohol-based hand sanitizers in terms of detection of methanol adulteration and quantification of ethanol is presented. Detection of adulterated methanol is carried out based on Schiff's reagent after the oxidation of methanol to formaldehyde, giving a bluish-purple solution to detect at 591 nm. In cases where a colorless solution is observed, an iodoform reaction with turbidimetric detection is then performed for quantitative analysis of legal alcohol (ethanol or isopropanol). To comply with the regulation of quality assessment of alcohol-based hand sanitizers, a regulation chart with four safety zones is also presented, employing a combination of two developed tests. The coordinates of a point (x, y) obtained from the two tests are extrapolated to the safety zone in the regulation chart. The regulation chart also showed consistency of analytical results as compared with the gas chromatography-flame ionization detector.