The ‘saliva’ has been created in the laboratory by researchers at the University of Leeds in the UK. Made up of two layers of gel, it is able to bind to the mucous membranes inside the mouth with a longer-lasting effect and greater ‘strength’ than other substances used until now.
A dry mouth (the medical name for which is xerostomia), resulting from insufficient saliva production, is a common condition affecting one in ten people. It can adversely impact quality of life, making talking and eating tricky for some. This disorder is very often associated with using certain medicines (more than 400 have been listed as having this side effect), and with cancer treatments in particular (chemotherapy and radiotherapy). But ‘dry mouth’ is also prevalent among older people, and can make oral and dental diseases worse.
Various remedies exist to try to alleviate a dry mouth, depending on the individual’s circumstances. Among these are substances that can stimulate saliva production, but ‘substitutes’ of the saliva itself are also prescribed. However, many of these products fail to have a truly curative, long-lasting effect, and need to be reapplied or used frequently. But now, an 'artificial’ saliva developed by researchers at the University of Leeds in the UK holds promise of having properties that could represent a real breakthrough: this new compound appears able to remain in the oral cavity for a long time, and the British scientists say it is four to five times more effective than similar substances as a result.
A two-layered gel to combat dry mouth
As written in the Nature Portfolio journal Scientific Reports, the new ‘saliva’ is made up of two types of gel: a more inner microgel, and a more outer hydrogel (with a higher water content). Together, these create a lattice-like network — or a sponge, we could say — with the capacity to bind firmly to the mucous membranes.
The new artificial saliva has demonstrated its innovative properties through testing on laboratory materials that replicate the characteristics of the human tongue, and has been benchmarked against eight of the most common commercially available compounds. The researchers write that while the reference products instantly lose 23% to 58% of their lubricant, the ‘saliva’ designed in Leeds loses only 7%. This is because the structure of the novel substance allows it to bind effectively to the mucous membranes, and it is not ‘rinsed’ away quickly (in technical terms, it is said to have excellent ‘adsorption’). It also shows outstanding performance in terms of lubrication (which is vital for eating), moistness and, of course, strength.
There’s even a vegan version
To produce commercially viable products, the researchers have made two versions: one containing milk proteins, which is slightly more effective, and one for vegans that contains purely plant proteins (mainly extracted from potatoes). In any case, these ingredients are non-toxic to humans and are free from calories, the scientists assure. Trials in volunteers will start soon.
