Nanoparticle delivery maximizes drug defense against bioterrorism agent

Posted on

Zink Jeffreysmall

Professor Jeffrey Zink and graduate student Zilu Li are part of a team that has developed a method for improving antibiotic’s efficacy while reducing side effects.         

Their research was published in the October 5th issue of the journal ACS Nano in a paper titled “Mesoporous Silica Nanoparticles with pH-Sensitive Nanovalves for Delivery of Moxifloxacin Provide Improved Treatment of Lethal Pneumonic Tularemia”. 

The team’s research shows how the nanoparticle system targets the precise cells infected by the bacteria and maximizes the amount of drug delivered to those cells.

The other members of the research team are Professor Daniel Clemens, UCLA Department of Medicine; co-senior author Professor Marcus Horwitz, Department of Medicine Infectious Diseases and Microbiology, Immunology & Molecular Genetics; and Horwitz group members Bai-Yu Lee, an associate researcher, and Barbara Jane Dillon, a staff research associate.

From UCLA Newsroom (by Shaun Mason):

Scientists from the California NanoSystems Institute at UCLA have developed a nanoparticle delivery system for the antibiotic moxifloxacin that vastly improves the drug’s effectiveness against pneumonic tularemia, a type of pneumonia caused by inhalation of the bacterium Francisella tularensis.

The study, which appears in the journal ACS Nano, shows how the nanoparticle system targets the precise cells infected by the bacteria and maximizes the amount of drug delivered to those cells.

Horwitz Zink%20team

The Horwitz/Zink research team (left to right): Daniel Clemens, Bai-Yu Lee, Marcus Horwitz, Jeffrey Zink, Barbara Jane Dillon and Zilu Li. 

Jeffrey Zink, distinguished professor of chemistry and biochemistry and a senior author on the study, developed the mesoporous silica nanoparticles used for drug delivery. Zink and his research team conducted an exhaustive process to find the best particle for the job.

“The nanoparticles are full of deep empty pores,” Zink said. “We place the particles in drug solution overnight, filling the pores with drug molecules. We then block the pore openings on the nanoparticle’s surface with molecules called nanovalves, sealing the drug inside the nanoparticle.”

When the drug-bearing nanoparticles are injected into the infected animal, in this case a mouse, the drug stays in the nanoparticles until they reach their target: white blood cells called macrophages. Macrophages ingest nanoparticles into compartments that have an acidic environment. The nanovalves, which are designed to open in response to the more acidic surroundings, then release the drug.

“We tested several different particles and nanovalves until we found the ones that would carry the maximum amount of drug and release it at just the right pH value,” Zink said.

Read full article here.

To learn more about Professor Zink’s research visit his group’s website.

Photo by Tunde Akinloye for CNSI.