Scientists develop targeted laser therapy to deactivate acne-causing glands

More work needs to be done to analyse the potential side effects of the therapy, such as follicular damage, but the ‘photothermolysis’ method developed by researchers at UC Santa Barbara, is particularly suited to patients with advanced, severe or difficult-to-treat acne.

The research, published in the Journal of Controlled Release​, has gone from concept to clinical trials in a relatively short amount of time and sees a combination of ultrasound, gold-covered particles and lasers, potentially lessen the frequency and intensity of breakouts.

Targeted therapy​

"Through this unique collaboration, we have essentially established the foundation of a novel therapy,"​ says Samir Mitragotri, professor of chemical engineering at UCSB.

The new technology builds on Mitragotri's specialties in targeted therapy and transdermal drug delivery.

It uses a low-frequency ultrasound in which gold-coated silica particles are pushed through the follicle into the sebaceous glands, where they are then heated by the laser.

The heated particles essentially cause deactivation of the sebaceous glands. The sebum, pore-blocking substances and particles are excreted normally.

"The unique thing about these particles is that when you shine a laser on them, they efficiently convert light into heat via a process called surface plasmon resonance,"​ continues Mitragotri.

This also marks the first time ultrasound, which has been proved for years to deliver drugs through the skin, has been used to deliver the particles into humans.

Samir Mitragotri

"If you deactivate these overproducing glands, you're basically treating the root cause of the acne."

Research method​

Postdoctoral research associate Byeong Hee Hwang, now an assistant professor at Incheon National University, conducted research at UCSB.

Called selective photothermolysis, the method does not irritate or dry the skin's surface. In addition, it poses no risk of resistance or long-term side effects that can occur with antibiotics or other systemic treatments.

"It's highly local but highly potent as well,"​ Mitragotri says of the treatment. "I think this would be beneficial in addressing the concerns regarding other, conventional treatments."​

Spot the problem​

Pimples form when follicles get blocked by sebum, an oily, waxy substance secreted by sebaceous glands located adjacent to the follicle. Excretion of sebum is a natural process and functions to lubricate and waterproof the skin.

Occasionally, however, pores get blocked, typically by bits of hair, skin, dirt or other debris mixed in with the sebum. Overproduction of sebum is also a problem, which can be caused by hormones or medications.

Changes in the skin, such as its thickening during puberty, can also contribute to follicle blockage. Whatever the cause, the accumulating sebum harbours bacteria, which results in the inflammation and local infection that we call acne.