There is growing interest in active ingredients of natural or biotechnological origin, such as hyaluronic acid, which is used in dermo-aesthetic products such as anti-ageing products for the skin and dermal fillers, among others. But how do you measure this ingredient in a formulation?

How is hyaluronic acid measured in products ?

Hyaluronic acid (HA) or sodium hyaluronate (NaHA) is a dermo-aesthetic active ingredient currently in vogue. HA, often of biotechnological origin, is a hydrogel belonging to the glycosaminoglycan class. These are complex polysaccharides that constitute a class of natural polymers made up of linked monosaccharide molecules, but whose structure and properties vary considerably from one group of substances to another.

In recent years, this ingredient has been used in all areas of activity linked to health and the quest for ‘eternal youth’. From medical applications to filling injections, to food supplements of all kinds (drinkable solutions, capsules, etc.) and cosmetic products.

The presence of these molecules in all these fields highlights the complexity of analysing them using unique methods.

However, quantitative analysis of HA can be performed accurately and reliably over a wide concentration range (μg/g to mg/g) regardless of its molecular weight. This property is the result of a homogeneous overall electrical charge throughout the chain of this polysaccharide. The charge/size ratio is therefore independent of molecular weight and does not affect the resolving power of this analysis for this molecule.

In addition to measuring hyaluronic acid, it is also possible to measure the molecular weight of HA chains.

Modification of hyaluronic acid – what is it ?

Although natural hyaluronic acid has interesting properties such as hydration and biocompatibility, it has certain limitations:

– Rapid degradation in the body by enzymes (hyaluronidases).
– Insufficient viscosity for certain applications.
– Instability over time or under certain physiological conditions.

To overcome these limitations, chemical modifications can be made to the functional groups of hyaluronic acid (generally hydroxyl or carboxyl groups). These modifications can include cross-linking, grafting of side chains, or substitution by specific chemical groups.

Measuring the rate of modification

Measuring the rate of modification of hyaluronic acid (HA) refers to the quantification of chemical modifications made to this molecule to alter its physico-chemical properties, in order to make it more suitable for specific applications. These modifications are often introduced to improve its stability, biocompatibility or duration of action. Here too, analysis can guide formulation choices.

 

 

CONCLUSION

Ready to innovate with hyaluronic acid? Quantitative and qualitative analysis can help you get the most out of your innovations and/or developments. Hyaluronic acid is an active ingredient of natural or biotechnological origin, which has not finished seducing.

If you want to work with experts to innovate around hyaluronic acid, call on our services

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