Perinelli Diego R, Berardi Alberto, Bisharat Lorina, Cambriani Alessandra, Ganzetti Roberta, Bonacucina Giulia, Cespi Marco, Palmieri Giovanni F
School of Pharmacy, University of Camerino, Camerino, MC 62032, Italy.
Faculty of Pharmacy, Applied Science Private University, Amman 11931, Jordan.
Int J Pharm. 2021 Jul 15;604:120769. doi: 10.1016/j.ijpharm.2021.120769. Epub 2021 Jun 3.
Cellulosic-based thickeners are commonly used in the preparation of hydro-alcoholic hand sanitisers. Yet, little is known about the behaviour of these polymeric dispersions in hydro-alcoholic mixtures. Here, we studied the dispersion ability and rheology of hydroxyethyl cellulose, hydroxypropyl cellulose, hydroxypropyl methylcellulose and sodium carboxymethyl cellulose in water-ethanol mixtures. Hydroxypropyl cellulose formed transparent dispersions across the entire range of ethanol concentrations, while a critical ethanol concentration (CEC), above which dispersions became turbid, was found for all the other polymers. At and below the CEC, all the rheological parameters followed a bell-like shape profile as a function of ethanol concentration. Moreover, the molecular weight and degree of substitution of the polymers influenced the rheological properties. The CEC and rheological behaviour of the dispersions were both dependent on the ethanol/polymer and water/polymer interactions. As hand disinfectants should contain 60-95% ethanol, polymers of higher CEC, such as hydroxypropyl cellulose and hydroxypropyl methylcellulose, are recommended.
纤维素基增稠剂常用于制备水醇型洗手液。然而，对于这些聚合物分散体在水醇混合物中的行为知之甚少。在此，我们研究了羟乙基纤维素、羟丙基纤维素、羟丙基甲基纤维素和羧甲基纤维素钠在水 - 乙醇混合物中的分散能力和流变学特性。羟丙基纤维素在整个乙醇浓度范围内形成透明分散体，而对于所有其他聚合物，发现了一个临界乙醇浓度（CEC），高于该浓度分散体变得浑浊。在CEC及以下，所有流变参数随乙醇浓度呈钟形曲线。此外，聚合物的分子量和取代度影响流变性能。分散体的CEC和流变行为均取决于乙醇/聚合物和水/聚合物相互作用。由于手部消毒剂应含有60 - 95%的乙醇，推荐使用CEC较高的聚合物，如羟丙基纤维素和羟丙基甲基纤维素。
