Future tampons could absorb 3 TIMES more menstrual blood than current feminine products – thanks to a new hydrogel sheet that absorbs an ounce of liquid in 60 seconds
- Scientists created a gelatin-like material containing a polymer that they then formed into a soft, flexible sheet
- Tests have shown it can absorb three times more than traditional tampons
- Scientists are now looking to strengthen the material and develop reusable sheets for the market
A new superabsorbent bandage that can absorb three times more liquid will transform traditional tampons and sanitary napkins.
The sheet is made of a gelatin-like material containing a polymer, which can absorb more than an ounce of blood in 60 seconds – current gauze dressings only capture 55% of the amount.
The gel sheet also worked well with syrup, blood, and even liquids that are a million times thicker than water.
Scientists are now looking to strengthen the material and develop reusable sheets for the market.
Professor Srinivasa Raghavan from the University of Maryland and co-author of the study said: “In principle, gel sheets could be a superior form of paper towels.”
Scientists have created a superabsorbent hydrogel sheet. The group claims it can hold three times as much blood as current plasters
There are generally two materials that absorb liquids: porous materials and hydrogels.
Cloth and paper are porous materials and although they are flexible, they are not very absorbent.
On the other hand, superabsorbent polymer hydrogels, a fabric of large molecules, can absorb more than 100 times their weight in water.
However, once dried, these hydrogels become brittle solids that crumble.
“We’ve reinvented what a hydrogel can look like,” Raghavan told SWS.
“What we’ve done is combine the desired properties of a paper towel and a hydrogel.”
The road to super-absorbent began with the team mixing a chemical cocktail – including acid – in a zip-lock bag.
“Like vinegar meets baking soda, carbon dioxide bubbles developed in the gel,” the researchers said.
Once a foam-like material formed from the concoction, the team sandwiched it between slabs of glass until it developed into a sheet, which has then exposed to UV light. The liquid settles around the bubbles – leaving the pores behind.
Finally, the leaf was soaked in alcohol and glycerol and air dried, which kept it soft and flexible.
“To our knowledge, this is the first hydrogel reported to have such tactile and mechanical properties,” Raghavan said.
The gel sheets also remained soft and flexible under ambient conditions for one year, indicating stability.
“We try to achieve unique properties with simple raw materials,” Raghavan said.
Compared to a commercial cloth pad and a paper towel, the same size gel sheet can absorb more than three times the amount of liquid.
The sheet is made of a gelatin-like material containing a polymer, which can absorb over an ounce of blood in 60 seconds. The left is the new sheet and the right is a traditional dressing
The new gel sheet (left) also picked up all the fluid in testing, while the gauze dressing (right) barely absorbed any fluid
When the researchers placed it over 0.8 ounces of spilled water, the leaf swelled and absorbed it within 20 seconds, retaining the water without dripping.
The cloth pad only absorbed about 60% and left some drips.
The gel sheet also holds its liquid well, while the blood-soaked gauze drips off. It absorbs more than twice as much blood as sanitary napkins, sponges and gauze.
Raghavan and his colleagues now plan to optimize the product by increasing absorption.
Due to their flexible and absorbent nature, gel sheets can also potentially stop bleeding from severe wounds as a dressing.