Of many cosmetics and personal care products that are used in everyday life, most contain different types of PEGs. PEG stands for polyethylene glycol and is not a single chemical as such, but a mixture of bonded polymers. One of these compounds is PEG-7, which has, among others, softening, stabilizing and moisturising properties. Products containing PEG-7 are drugs, ointments, oral hygiene preparations and dermocosmetics.
One of the substances belonging to the group of polyoxyethylene glycols is a compound with the INCI name PEG-7 (CAS No. 25322-68-3). Its chemical name is polyoxyethylene glycol, but the term macrogol 300 is also used. It belongs to the group of macrogols (the pharmacopoeial name of polyethylene glycols for pharmaceutical use) due to the fulfilment of strict quality requirements, which have been defined in the latest edition of the European Pharmacopoeia. Very frequently, a number appears following the abbreviation PEG, for example PEG-8 or PEG-7. This number represents the approximate molecular weight of the compound. Typically, PEGs with a lower molecular weight are used in cosmetics and pharmaceutical preparations.
General characteristics of PEG-7:
PEG-7 has several key roles in products where it is one of the ingredients. First of all, it is a solvent for other components of a given formulation. Another role of PEG-7 is inherently linked to the physical process of dissolving. Te compound is referred to as a solubilizer. Solubilizers are surfactants co-responsible for introducing insoluble or sparingly soluble substances into an aqueous solution. Examples of such substances are: fragrance oils, plant extracts or fatty substances. PEG-7, in pharmaceutical formulations, improves the rheological properties of liquid preparations as well as ointments. The rheological properties, regulating the sedimentation rate of solid particles, significantly influence the stability of pharmaceutical suspensions. The accurately assured viscosity, due to the presence of PEG-7 in the composition, among others, contributes to the accuracy of dosing and facilitates the application of the preparation. Otherwise (when the substance particles sediment too quickly) it will be impossible to even deliver the required dose of the drug from the package. Macrogols such as PEG-7 also act as binding agents or active substances. Their other role is to act as humectants, i.e. agents which main role is to bind water contained in the pharmaceutical preparation. Due to this effect, it is possible to ensure even distribution of all ingredients. This compound is also used as a half-product for the synthesis of active substances. PEG-7 is safe and non-toxic. Moreover, a negative impact on the natural environment has not been found.
PEG-7 is one of the ingredients of the following products:
