Sontra Medical Corporation announced that the U.S. Patent and Trademark Office has issued patent (No. 6,491,657) covering Sontra's methods for enhancing transdermal transport. The patent describes the use of Sontra's SonoPrep hand-held ultrasound device to permeate the skin followed by the use of a driving force such as an osmotic pressure gradient, iontophoresis, electroporation, suction or mechanical pressure for transdermal drug delivery and the non-invasive diagnosis of interstitial analytes. The patent also describes a method of using an external electrochemical sensor to measure analytes drawn from the skin.

"This patent significantly broadens the proprietary technology platform that we are employing to develop products for the transdermal drug delivery and non-invasive diagnostic markets," stated Sontra's Chief Executive Officer and President, Dr. Thomas Davision. Sontra's unique ultrasound mediated skin permeation technology consistently increases skin permeability by 100 fold compared to untreated skin, and we have combined this core technology with our active transport and sensing technologies in developing our Symphony Diabetes Management System for continuous, non invasive glucose monitoring. In drug delivery, our SonoPrep device can significantly accelerate the onset of action of topically applied local drugs and transdermal systemic drugs. We have also demonstrated the potential of using our SonoPrep technology to deliver large molecule drugs and biopharmaceuticals transdermally."

Ultrasound-mediated skin permeation is a non-invasive and painless method for enhancing the flow of fluids and molecules across the skin's protective membrane. A fifteen second application of ultrasonic energy to the skin using the SonoPrep device creates reversible channels for up to twenty four hours through which analytes can be extracted and large molecules can be delivered.