Siberian scientists know how to protect eyes from chemical burns – they developed “contact lenses”, which turn dangerous liquids (like acids and alkalies) into safe ones (like water) – seems that magic is involved.

New development looks like small thin plates, reminding of contact lenses. Their structure contains particles of so-called ion exchange resin. Such plate, put under lower lid, is able to remove acid or alkali, eliminating or minimizing their damage of delicate eye tissues.

Of course, not magic does all mentioned things. Eye medical ion exchange pillows (EMIOPs) are based upon properties of ion exchange resins – polymers, which can change anions or cations, bound with polymer chain, to similar ions from surrounding solution. Such resins are called anion or cation exchangers, depending on the type of exchanged ions. This technique is well-known in chemistry, for instance, ion exchangers can purify a substance from unwanted ions by replacing them with required ions with same charge. By the way, despite resin is associated with something black and sticky, ion exchangers are usually solid translucent beads of pale yellow colour.

 

 

These are resins, which Russian scientists suggest using in ophthalmology. Chemical eye burns, caused by acids and alkalies, are very dangerous, and no treatment for them exists to the moment. Traditional techniques prescribe washing damaged eye first with fresh water, and then – with neutralizing solution. Say, when acid enters an eye, you should use sodium bicarbonate, and when damaging agent is alkaline, you should take boric acid instead. However, this technique almost always has no effect.

Of course, damaged eye should be washed with water, but it is not enough. Acids and alkalies tend to penetrate eye tissues very fast and keep attacking them from inside. Simple water washing won’t help. What is more, neutralization is a chemical reaction, which not only changes pH (pH is the measure of the acidity or alkalinity of a solution) of the environment, but also leads to formation of new reaction products, which may also be toxic.

 

 

Siberian researchers suggest new technique, which forms no reaction products, except water. Let us imagine that alkali somehow got into an eye. Alkali is a solution, containing cations of an alkali metal (usually potassium or sodium) and hydroxyl ions (which are responsible for high pH). In this case we need a resin, which absorbs metal cations, replacing them with hydrogen ions (protons), which immediately react with hydroxyl ions, forming water. We can also change hydroxyl ions to chloride ions, which are anions too, resulting in sodium chloride (table salt) solution, which is found in blood and in eyes and everywhere. Moreover, ion exchanger keeps working until all unwanted ions move from eye tissues and surroundings to polymer particles.

Sad aspect here is that lack of funds forced researchers to stop investigating and producing such useful plates. We hope that situation improves and EMIOPs will enter pharmacies to help all those, who need it.

Source: Russian Science News

Kizilova Anna