Drug-delivering tampons could protect women against HIV

The silk-line fibers dissolve within six minutes of contact with moisture, delivering the dosage necessary for maximum protection before sexual contact.

"This could offer women a potentially more effective, discreet way to protect themselves from HIV infection by inserting the drug-loaded materials into the vagina before sex," says lead author Cameron Ball, a UW doctoral student in bioengineering.

Now that a recipe exists for such topical drugs that prevent HIV, called microbiocides, delivering them has been a quandary due to the quantity required, which creates a high probability of leakage.

"The effectiveness of an anti-HIV topical drug depends partially on high-enough dosages and quick release," says Ball. "We have achieved higher drug loading in our material such that you wouldn't need to insert a large amount of these fibers to deliver enough of the drug to be helpful."

The research was inspired by bioengineering assistant professor Kim Woodrow's study in which her team found that electrically spun cloth could be dissolved to release drugs.

The tampons are fabricated by a process called electrospinning, which is roughly comparable on the large scale to the traditional spinning of yarn from wool.

Electrospinning, according to researchers, turns the liquid into extremely fine fibers, measurable on the micro-scale or even the nanoscale, and large or complex molecules are particularly suitable to the process.

A variety of topical HIV-prevention drugs are available and researchers say they are currently testing the effectiveness of several.

"We think the fiber platform technology has the capability of being developed into multifunctional medical fabrics that address simultaneously challenges related to biological efficacy and user preferences," says Woodrow.

Although it is currently referred to as a tampon, and could be inserted by means of a cardboard applicator as with conventional tampons, the method is not to be confused with menstrual hygiene, for the material is not meant to absorb blood.

Researchers are exploring other delivery methods such as a vaginal ring similar to the contraception device and so far the product has not been tested on humans.

Woodrow says the method could eventually expand into other domains of sexual health, even contraception.

"Our dream is to create a product women can use to protect themselves from HIV infection and unintended pregnancy," she said in an interview upon the publication of her paper on electrospinning.