IPN-Like Technology

Technology on the Move


All VIVACY’s products are hyaluronic acid-based. Hyaluronic acid (HA) is a naturally occurring molecule in the human body, particularly in the skin and mucous membranes. It can retain up to 1,000 times its weight in water2, consequently contributing to the hydration and toning of the concerned tissues3.

HA has a short life span and is soluble in water, meaning it needs to be stabilised before injection into skin tissues. To do so, a special technical process called “cross-linking” is used to bind HA molecules together to obtain a cohesive HA gel for a skin smoothing, lifting and/or volumising effect that will last for several months. The duration of the treatment depends on many factors, such as the patient’s skin type and structure, age, lifestyle, the area treated and the injection technique used by the practitioner.




Laboratoires VIVACY has developed “IPN-Like Technology” (InterPenetrated Networks), a unique cross-linking technology for hyaluronic acid that accurately defines each product’s viscoelastic properties4.

From a clinical standpoint, the main product characteristics sought after by Physicians are their ability to lift skin tissues, provide mechanical support and spread easily. To obtain these desired effects, the HA gel must have a unique combination of elasticity and viscosity5 .

These specific viscoelastic properties determine where the gel will be injected, allowing it to respond to the various mechanical stresses to which it will be subjected in the tissues.

As a result, the interpenetration of HA cross-linked networks4:

  • Optimises the products’ rheology, in particular the viscosity to guarantee good product injectability.
  • Preserves the partial independence of the interpenetrated HA networks, whilst increasing the density of chemical nodes.
  • Guarantees the cohesion of the HA gel and its monophasic properties.


During an intradermal injection, the invasive movement of the needle through the skin’s layers provokes an inflammatory response and the production of Free Radicals. These Free Radicals are harmful for hyaluronic acid molecules because they speed up their degradation3, causing the injected filler to break down more quickly and the duration of the correction effect to be reduced.

In order to protect the HA gel’s formulation during the injection, VIVACY has incorporated antioxidants into its filler products: Mannitol or Sorbitol. These antioxidant agents act as active scavengers6 against the most aggressive hydroxyl radicals generated during the injection process. As a result, they work to minimize the rapid break down of the injected hyaluronic acid gel7,8.


1- Papakonstantinou, E. & Al. Hyaluronic acid - A key molecule in skin aging. Dermato-Endocrinology 4:3, 253–258; July–December 2012.
2- Ulf Anderegg, J. C. S. & Al. More than just a filler – the role of hyaluronan for skin homeostasis. Experimental Dermatology, 2014, 23, 295–303.
3- Becker, L. C. & Al. “Final Report of the Safety Assessment of Hyaluronic Acid, Potassium Hyaluronate, and Sodium Hyaluronate” International Journal of Toxicology, 2009, volume 28 Number 4S, 5-67.
4- IPN-Like Technology Patent delivered WO2009/071697 in 2008.
5- Sundaram, H. & Al., “Biophysical characteristics of hyaluronic acid soft-tissue fillers and their relevance to aesthetic applications”. American Society of Plastic Surgeons, Plast. Reconstr. Surg. 132: 5S, 2013.
6- Smirnoff, N., Cumbes, Q. J. “Hydroxyl radical scavenging activity of compatible solutes”. Journal of Phytochemistry, Vol. 28, no. 4, pp. 1057-1060, 1989.
7- Mendoza G & Al. “Inhibitory effects of different antioxidants on hyaluronan depolymerisation” Carbohydr Res. 2007 Jan 15;342(1):96-102.
8- Mongkhon, J.-M. & Al. “Sorbitol-modified hyaluronic acid reduces oxidative stress, apoptosis and mediators of inflammation and catabolism in human osteoarthritic chondrocytes”. Inflamm. Res., 2014.