The term biopolymer refers to covalent monomer chain constructions obtained by chemically modifying natural biological substances or generated through biotechnological processes. They are generally nontoxic, biocompatible and biodegradable materials.
Unlike synthetic polymers, they are not produced by chemical synthesis and do not retain precise shapes or structures. Biopolymers are essential ingredients in cosmetic formulations. They act as rheology modifiers, emulsifiers, conditioners, filmogens, fixing agents, foam stabilizers, moisturizers and antimicrobials. Recently, they have also attracted interest because of their conspicuous metabolic activity on skin and skin adnexa.
Biopolymers used for cosmetic applications can be classified into two main types: polysaccharide-based and consisting of proteins.
The review
This paper, published in the International Journal of Cosmetic Science, provides an overview of the main biopolymers used in beauty and describes their sources, recently derived structures, new applications, and safety aspects of use.
The review opens with a distinction between protein biopolymers and biopolymers composed of polysaccharides. Regarding protein-based materials, collagen and derivatives, elastin and derivatives, silk and keratin are reviewed.In the polysaccharide category, however, the review focuses on chitosan and derivatives, hyaluronic acid and derivatives, sodium alginate and derivatives, starch and derivatives, xanthan gum, and carrageenan and derivatives.
Conclusions
Polymers of natural or synthetic origin have different characteristics and therefore have a variety of applications in cosmetics.Protein and polysaccharide structures are frequently included in conventional formulations as emulsifiers, rheology modifiers, film-forming agents, and foam stabilizers.
In the age of nanotechnology, the development of new carriers and modifications to classical biopolymers have produced raw materials capable of enhancing the stability of molecules or the finished product, improving its sensory characteristics, and providing technological and/or marketing advantages.
The biodegradability, biocompatibility and non-toxicity of the raw materials under study are valuable peculiarities. Indeed, they can be exploited in the design of beauty products that require safety and environmental compatibility claims.
Extensive test results support the low toxicity and safety of biopolymers as cosmetic ingredients.
It is, however, necessary to pay attention to the concentrations used, consumer idiosyncrasies, and the possibility of incorrect quantification of harmful residues from natural sources.In the future, promising applications of such materials are expected in the form of coatings, hydrogels, nanocarriers, and dermal fillers, some with antioxidant properties.
Presumably, new regulations will tend to insist on the use of sophisticated methodologies to analyze compounds derived from relatively new natural sources (e.g., marine species) to ensure that they meet quality parameters and in no way affect consumer health or customer satisfaction.
Mendoza-Muñoz N, Leyva-Gómez G, Piñón-Segundo E, Zambrano-Zaragoza ML, Quintanar-Guerrero D, Del Prado Audelo ML, et al.; Trends in biopolymer science applied to cosmetics; Int J Cosmet Sci. 2023; 00: 1–26. https://doi.org/10.1111/ics.12880