Assistant professor Omathanu Perumal of SDSU's Department of Pharmaceutical Sciences, shown here in the foreground of his laboratory, works with graduate student Satheesh Podaralla in research to deliver cancer medications using a protein from distillers grains.

The key to a better drug delivery method for cancer patients may be growing all across the Midwest, South Dakota State University research suggests.

Assistant Professor Omathanu Perumal and his team in SDSU's Department of Pharmaceutical Sciences have been working with submicroscopic particles to deliver medications using the corn protein, zein.

Zein is a protein found in distillers grains, a co-product of ethanol production . It is different from other proteins in its unique ability to prevent water absorption. This quality of zein has found applications ranging from food packaging to chewing gums.

Researchers at SDSU are preparing tiny zein particles nanoparticles for drug delivery. The nanoparticles are so small they can only be seen with an electron microscope.

SDSU scientists are working on entrapping a medication inside the nanoparticles, which Perumal notes are approximately 500 times smaller than the diameter of a strand of human hair.

The tiny size of these particles could lend assistance to new cancer therapies, where one challenge is treating the cancer cells without affecting the normal cells around it.

"We can utilize size," explains Perumal. "In general, the cancerous tissue is physiologically different from the normal tissue.

"One of the things we see in the tumor tissue is that the blood vessels are much 'leakier,' whereas normal blood vessels don't allow particles to be transported through them. Therefore, if you have really small particles, they will not go into normal tissue, but they can go into the cancerous tissue. This is called passive targeting." The drug-loaded zein nanoparticles are being delivered by injection in animal experiments , but future tests may explore oral, topical and other delivery methods, according to the State researchers.

When outside objects, including medications, get inside the body, the body's immune system tries to get them out of the body. This, in turn, affects the length of time that drugs can work in the body before being expelled. But the nanoparticles Perumal and his team are studying are so tiny that the body doesn't recognize and excrete them. Biodegradable alternative

In the technique SDSU is exploring, drugs are encapsulated within the nanoparticles and delivered to the affected site. Perumal became interested in using corn zein to form nanoparticles because it satisfied a safe, biodegradable alternative to using a synthetic ingredient and could target specific areas because of its size. Helps reduce dosage

The dosage frequency is also reduced because the medication stays longer in the body. Perumal adds that many people, because of religious reasons, don't take in animal proteins. That is one more reason to develop treatment options that use plant-based zein.

The team is currently working with a drug commonly used in treating breast cancer. They are experimenting with how much of the dose is delivered and its effectiveness compared to traditional methods of delivery. Perumal said the results show the treatment is meeting expectations.

Perumal's work has been funded by the South Dakota Corn Utilization Council. SDSU has filed a provisional patent and the researchers are moving forward with early pre-clinical studies using mice. Corn-based heart stents?

Although his team is now working with human breast cancer cells, Perumal anticipates the possibility of expanding nanoparticle treatment for other conditions . For those with artery blockage around the heart, synthetic stents are inserted to help keep the artery open. Because the stent is a foreign object, the body sometimes tries to combat its existence, causing inflammation. By coating the stent with drug-loaded nanoparticles, Perumal hopes that this would be prevented.

As the research enters its third year, Perumal will continue trials with support from the South Dakota Board of Regents.