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. 2022 Jan 29;8(2):87.
doi: 10.3390/gels8020087.

Alcohol-Based Hand Sanitizers: Does Gelling Agent Really Matter?

Ivana d'Angelo  1 , Romina Provenzano  2 , Ettore Florio  3 , Chiara Pagliuca  4 , Giuseppe Mantova  4 , Elena Scaglione  4 , Mariateresa Vitiello  4 , Roberta Colicchio  4 , Paola Salvatore  4   5   6 , Francesca Ungaro  2 , Fabiana Quaglia  2 , Agnese Miro  2
Affiliations

Alcohol-Based Hand Sanitizers: Does Gelling Agent Really Matter?

Ivana d'Angelo et al. Gels. .

Abstract

Hand hygiene, social distancing, and face covering are considered the first protection against Coronavirus spreading. The high demand during the COVID-19 emergency has driven a frenetic production and marketing of hand sanitizer gels. Nevertheless, the effect of the gelling agent and its amount on the effectiveness of alcohol-based hand sanitizers (ABHSs) needs to be clarified. We presented a systematic study on the effect of the characteristics and concentration of the most employed excipients on the properties and antimicrobial activity of ABHSs. Three different gelling agents, carbopol, hydroxypropylmethylcellulose (HPMC), and hydroxyethylcellulose (HEC), at four different concentrations were used to prepare ABHSs. Viscosity, spreadability, delivery from commercial dispensers, evaporation rate, rubbing time, and hand distribution of the ABHSs were then explored. Biocidal activity of selected ABHSs was evaluated in vitro on ATCC and clinical strains. The studied ABHS can be considered bioactive and comfortable. Nevertheless, the cellulose polymers and ethanol interactions led to a slight but significant reduction in the biocidal activity compared with carbopol-based formulations. Our results underline the importance of the gelling agent properties and support the choice of carbopol as one of the best thickener agents in ABHS formulations.

Keywords: COVID-19; alcohol-based hand sanitizers; thickener agents.

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Conflict of interest statement

The authors declare no conflict of interest.

Figures

Figure 1
Figure 1
Viscosity vs. shear-rate curves of alcohol-based gel sanitizers. The curve is the average of three measures. (a,b) Carbopol-based gels; (c,d) HPMC-based gels; (e,f) HEC-based gels.
Figure 2
Figure 2
Viscosity and spreadability of alcohol-based hand sanitizers. (a) Carbopol-based ABHS; (b) HPMC-based ABHS; and (c) HEC-based ABHS.
Figure 3
Figure 3
Relationship between viscosity and spreadability of the alcohol-based gels. Spreadability plotted against the viscosity of gel based on carbopol (a), HPMC (b), and HEC (c).
Figure 4
Figure 4
The hydro-alcoholic solvent evaporation rate from gels. The results are reported as weight of gel percentage in the time. (a,b) Carbopol-based gels; (c,d) HPMC-based gels; (e,f) HEC-based gels.
Figure 5
Figure 5
Gel amount delivered by the commercially available bottles: (a) push pump and (b) spray dispenser.
Figure 6
Figure 6
The gel dry time by rubbing. The results are reported as time needed to achieve complete drying by rubbing a known amount of gel on the hands of volunteers. (a) Carbopol-based gels; (b) HPMC-based gels; (c) HEC-based gels.
Figure 7
Figure 7
Distribution of fluorescent gels on hands after rubbing. (a) Carbopol-based gels containing 2% Glycerin (Carb_Gly 2%); (b) carbopol-based gels containing 0.5% Glycerin (Carb_Gly 0.5%); (c) HPMC-based gels containing 2% Glycerin (HPMC_Gly 2%); (d) HPMC-based gels containing 0.5% Glycerin (HPMC_Gly 0.5%); (e) HEC-based gels containing 2% Glycerin (HEC_Gly 2%); (f) HEC-based gels containing 0.5% Glycerin (HEC_Gly 0.5%). Representative images are shown.
Figure 7
Figure 7
Distribution of fluorescent gels on hands after rubbing. (a) Carbopol-based gels containing 2% Glycerin (Carb_Gly 2%); (b) carbopol-based gels containing 0.5% Glycerin (Carb_Gly 0.5%); (c) HPMC-based gels containing 2% Glycerin (HPMC_Gly 2%); (d) HPMC-based gels containing 0.5% Glycerin (HPMC_Gly 0.5%); (e) HEC-based gels containing 2% Glycerin (HEC_Gly 2%); (f) HEC-based gels containing 0.5% Glycerin (HEC_Gly 0.5%). Representative images are shown.
Figure 7
Figure 7
Distribution of fluorescent gels on hands after rubbing. (a) Carbopol-based gels containing 2% Glycerin (Carb_Gly 2%); (b) carbopol-based gels containing 0.5% Glycerin (Carb_Gly 0.5%); (c) HPMC-based gels containing 2% Glycerin (HPMC_Gly 2%); (d) HPMC-based gels containing 0.5% Glycerin (HPMC_Gly 0.5%); (e) HEC-based gels containing 2% Glycerin (HEC_Gly 2%); (f) HEC-based gels containing 0.5% Glycerin (HEC_Gly 0.5%). Representative images are shown.
Figure 7
Figure 7
Distribution of fluorescent gels on hands after rubbing. (a) Carbopol-based gels containing 2% Glycerin (Carb_Gly 2%); (b) carbopol-based gels containing 0.5% Glycerin (Carb_Gly 0.5%); (c) HPMC-based gels containing 2% Glycerin (HPMC_Gly 2%); (d) HPMC-based gels containing 0.5% Glycerin (HPMC_Gly 0.5%); (e) HEC-based gels containing 2% Glycerin (HEC_Gly 2%); (f) HEC-based gels containing 0.5% Glycerin (HEC_Gly 0.5%). Representative images are shown.
Figure 8
Figure 8
In vitro antimicrobial activity of alcohol-based gels against Gram-negative bacteria (a) and Gram-positive bacteria (b) (* p < 0.05, ** p < 0.01, *** p < 0.001 and **** p < 0.0001).
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References

    1. World Health Organization . World Alliance for Patient Safety: Forward Programme, 2005. World Health Organization; Geneva, Switzerland: 2004.
    1. Lopez A.D., Mathers C.D., Ezzati M., Jamison D.T., Murray C.J. Global and Regional Burden of Disease and Risk Factors, 2001: Systematic Analysis of Population Health Data. Lancet. 2006;367:1747–1757. doi: 10.1016/S0140-6736(06)68770-9. - DOI - PubMed
    1. World Health Organization (WHO) WHO Guidelines on Hand Hygiene in Health Care: First Global Patient Safety Challenge Clean Care Is Safer Care. World Health Organization; Geneva, Switzerland: 2009. - PubMed
    1. Kac G., Podglajen I., Gueneret M., Vaupré S., Bissery A., Meyer G. Microbiological Evaluation of Two Hand Hygiene Procedures Achieved by Healthcare Workers during Routine Patient Care: A Randomized Study. J. Hosp. Infect. 2005;60:32–39. doi: 10.1016/j.jhin.2004.10.014. - DOI - PubMed
    1. Golin A.P., Bhsc D.C., Ghahary A. Hand Sanitizers: A Review of Ingredients, Mechanisms of Action, Modes of Delivery, and Efficacy against Coronaviruses. Am. J. Infect. Control. 2020;48:11062–11067. doi: 10.1016/j.ajic.2020.06.182. - DOI - PMC - PubMed

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