Two UPC researchers create a new generation of smart surgical meshes to treat abdominal and groin hernias

Every year, over 20 million surgeries are performed worldwide to repair hernias, most of which are in the abdominal or groin areas. The most effective technique to repair the damaged tissue, whether through open surgery or laparoscopy, is the insertion of a surgical mesh.

Now, as part of the European project 4D-POLYSENSE, the Innovation in Materials and Molecular Engineering Group (IMEM), associated with the Barcelona East School of Engineering (EEBE) of the Universitat Politècnica de Catalunya · BarcelonaTech (UPC), has developed a new generation of non-absorbable surgical meshes, with a biocompatible hydrogel layer, designed to help to reduce problems relating to the implantation of rigid polymer materials in areas that are in contact with delicate tissues of the abdominal wall. The key is the smart material with which they are designed: a thermosensitive polymeric gel that can respond to changes in temperature and adapt to the soft tissues by changing shape.

How does the thermosensitive hydrogel act?
Hydrogels are a type of polymeric material that can retain a large quantity of liquid without dissolving. Thermosensitive hydrogels have swelling properties that are modulated by temperature changes. Therefore, in contact with body temperature, the material can expand or contract to adapt to the implantation area. This effect, called the ‘4D response’ or dynamic effect, is achieved by the hydrogel coating on the polypropylene threads of the mesh, which give it the capacity to respond to changes in temperature and humidity.

As explained by the main researcher on the project, Elaine Armelin, from the IMEM, “for the first time, a non-absorbable surgical mesh has been obtained that can offer properties of adaptability depending on the temperature and humidity in the local environment where it will be implanted.” This is the first surgical mesh that can respond to changes in temperature of 25 to 40 degrees centigrade.

The research is currently in the laboratory phase (in vitro). In an article published recently in the scientific journal Advanced Functional Materials, the UPC researchers explained how a static polypropylene mesh could become a dynamic system and how its structural properties change. As Armelin stated, “the manufacture of conventional surgical meshes is based on textile technology, which is widely known, and transforms polymer fibres (1D) into a two-dimensional textile structure (2D). Due to the hydrogel deposition, the 2D structure becomes a smart material that can respond to various stimuli, such as changes in local temperature, to provide an active, dynamic structure with movement capacity so that it can adapt to the environment. It is what is known as 4D technology”.

This capacity for modulation and adaptation of the material will be very useful in surgery. It will facilitate manipulation by the medical team during implantation, and post-operatively it will enable better adaptation of the surrounding tissue and minimization of the risk of pain post-implantation for the patient. “The adaptive effect of the mesh is designed to help to reduce the risk of inflammatory processes that could occur after the surgical intervention, which would lead to an improvement in the quality of life of operated patients, as well as savings for the health system, as it would minimise the risk of reintervention or reduce the medication required for chronic pain”, stated the researcher.