Scientists are developing a dissolvable "tampon" that could protect women against HIV

Researchers have created a high-tech fabric that can deliver women HIV drugs, and potentially contraceptive, quickly and easily.

For years researchers have been developing anti-HIV gels or creams known as microbicides, which women can apply to their vagina to help protect them against the virus. But the problem is the treatments can leak, are messy, inconsistent and take a long time to absorb, so women need to apply them at least 20 minutes before sex.

Now scientists at the University of Washington in Seattle have developed an electrically spun fabric that can deliver these drugs quickly and easily to a woman in the form of a dissolvable tampon.

Each thread of the polymer is around 200 times smaller than a human hair, and the researchers have found that high concentrations of HIV-preventing microbicide can be interwoven into the fabric. Importantly, it also dissolves quickly when it gets wet, so it can release high doses of the medication directly to a woman's vagina within six minutes.

"That means women don't have to apply it far in advance of having sex," bioengineer Cameron Ball, who worked on the new fabric, told Diane Cole at NPR. "There's a race between the anti-HIV microbicide to get to the tissue before the virus does. So the more quickly it dissolves, the better."

Studies in South Africa have shown that certain microbicide gels can reduce the transmission of HIV by around 54 percent. But scientists have so far have only managed to make creams and gels that contain 3 percent of the active drugs.

The University of Washington team have shown that the new nano-fibres, on the other hand, can successfully have almost 30 percent of their mass made up of microbicides thanks to their high surface area to volume ratio. Their results are published in the journal Antimicrobial Agents and Chemotherapy.

Although a tampon is one of the obvious ways this fabric could be structured at the moment, the team is also looking into other shapes.

"It's a matter of giving women enough choices and options of what products are available and how they are used," Ball told NPR. "So you meet the needs of as many women as possible." The scientists are also looking into ways this material can deliver the drug anally.

The team also wants to combine contraceptive spermicide and other microbicides into the fabric to create a device that can be discreetly inserted a few minutes before sex to protect against pregnancy, HIV, herpes and other sexually transmitted diseases all at the same time.

The bad news is that the material, which is used for pharmaceutical applications already, still needs to be tested in other animals before clinical trials in humans begin, all of which will take around 10 years. And even though the drug used in this original study already has US Food and Drug Administration (FDA) approval, some of the microbicides that could infuse the tampon are still undergoing clinical trials.

But the new technology is a big step forward in the control of HIV and will hopefully lead to a range of new prevention options.