Molecular Condom Helps Protect Against HIV.

Judit Fabian / University of Utah

Bioengineers from the University of Utah have developed a "molecular condom" that women can use to protect themselves against the AIDS virus:

These images reflect how the substance, known as a hydrogel, behaves at various temperatures and pHs (pH measures acidity or alkalinity). A woman would insert the substance vaginally as a liquid at room temperature. At body temperature and at the vaginal fluid pH of 4.2, it would become gel coating. Then, in the presence of male seminal fluid with a pH of 7.7, it would become a liquid again and release an antiviral drug to block infection by the human immunodeficiency virus.

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