Skip to Main Content

Strategic Business Insights (SBI) logo

Nanobiotechnology July 2014 Viewpoints

Technology Analyst: Lucy Young

RNAi Transportation

Why is this topic significant?

RNAi is a promising technique for suppressing the expression of genes. Nanotechnology has found use as a delivery vehicle for RNAi therapeutics, but researchers have struggled to deliver the siRNA to target locations with safe doses. New research may have discovered a way of achieving this feat by changing the chemistry of the nanoparticles.

Description

Researchers at the Massachusetts Institute of Technology (MIT) have created nanoparticles for delivering small interfering ribonucleic acid (siRNA) to a number of organs in the body. The team had previously demonstrated the delivery of siRNA to liver cells via nanoparticles. The liver cells absorbed the nanoparticles because of their resemblance to fatty droplets. The liver-cell-targeting ribonucleic-acid-interference (RNAi) therapeutic is in clinical development. However, nanoparticles in the bloodstream are likely to end up in the liver anyway. To deliver sufficient quantity of the nanoparticles and the RNAi therapy to other organs, researchers have relied on high doses of the therapeutic. These doses increase the risk to the patient.

In response, the MIT researchers created nanoparticles comprising at least three concentric spheres. These spheres consist of short chains of a chemically modified polymer. The scientists tested the ability of 2400 variants of the nanoparticle to prevent a gene in cervical cancer cells from creating an identifiable protein. Then they evaluated the best nanoparticles' ability to reduce gene expression of the TIE2 gene, which endothelial cells—cells that line most organs—express. The optimal particles—in a dosage one-hundredth the size of current RNAi therapies for endothelial cells—reduced the TIE2 gene expression by more than 50%. The nanoparticles performed best in lung endothelial cells but were also successful in other organs, including the heart and kidneys. The researchers also successfully demonstrated that their RNAi therapeutics could reduce the expression of VEGF receptor 1 and DII4—which causes blood vessels that feed tumors to grow—in the lungs of mice.

Implications

RNAi occurs in cells naturally to aid the cells' regulation of genes. It has great potential for targeting therapeutics to treat illnesses by switching off those genes that scientists know contribute to the disease. The small size and capabilities of nanoparticles make them excellent candidates for the specific transportation of the siRNA. The work of the MIT researchers has demonstrated that altering the chemistry of the nanoparticles can help to determine which parts of the body they travel to. Importantly, these nanoparticles now enable safer levels of dosage, increasing the likelihood of RNAi therapeutics' becoming commercially available. The nanoparticles also open up the opportunity for treating other diseases, including atherosclerosis and diabetic retinopathy.

Impacts/Disruptions

RNAi—along with other gene-expression-manipulating techniques—could have a significant impact on medicine and other biotechnology application areas such as genetically modified food. However, such techniques must undergo rigorous testing before they become commercially available. And, although the MIT nanoparticle may result in safer doses of RNAi therapeutics, the underlying general concerns about the toxicity of nanomaterials add another dimension to the regulatory process.

Scale of Impact

  • Low
  • Medium
  • High
The scale of impact for this topic is: Medium

Time of Impact

  • Now
  • 5 Years
  • 10 Years
  • 15 Years
The time of impact for this topic is: 10 Years to 15 Years

Opportunitites in the following industry areas:

Pharmaceuticals, medicine, food

Relevant to the following Explorer Technology Areas:

Plasmonic Interferometry and Diabetes

Why is this topic significant?

A new nanoscale technique is enabling the creation of very sensitive sensors. Researchers are using the technology to develop a noninvasive device for monitoring glucose levels in saliva.

Description

Researchers are finding nanotechnology useful for improving the techniques for measuring glucose. For example, Brown University scientists have used nanoscale plasmonic interferometry to detect 0.1-micromole-per-liter changes in glucose concentration—which improves the sensitivity of standard interferometry tenfold. A plasmonic interferometer consists of two 200-nanometer-wide grooves straddling a slit of 100 nanometers' width in a thin silver film. In the researchers' glucose-analysis work, they placed the silver film—with thousands of plasmonic interferometers etched on it—onto quartz. When light hits a plasmonic interferometer, the grooves create a surface-plasmon polariton—consisting of a wave of free electrons—in the silver that moves toward the slit and interferes with the light propagating through the slit. Detectors measure the patterns of interference that the grooves and slits cause. For a liquid sample, the light and free electrons will travel through the liquid before they interfere with one another, resulting in different interference patterns that vary depending on the chemical composition of the liquid. The Brown University researchers altered the distances between the grooves and slits in order to detect glucose molecules specifically.

The researchers were aiming to create a noninvasive form of glucose detection by using their device with saliva. However, enzymes and salts complicate plasmonic interferometry in saliva because they interfere with the detection process. To overcome the interference, the scientists introduced two enzymes—glucose oxidase and horseradish peroxidase—via microfluidic channels to cause the glucose to generate the molecule resorufin. Resorufin absorbs and emits red light, so the scientists altered the plasmonic interferometers to be sensitive to resorufin.

Implications

The researchers' development of the device to analyze saliva is a significant step forward for the technology. The scientists have tested the device with artificial saliva but aim to test it with real saliva and eventually build a self-contained chip for the noninvasive monitoring of glucose levels for diabetics. Plasmonic inferometry is very new, and—although its principles are based on well-established techniques—the technology will need to prove its worth in usefulness and commercial viability.

Impacts/Disruptions

In the wake of Google's announcement concerning its ongoing development of a contact lens that monitors glucose levels, technology that eases the burden of diabetes has received much press. However, development of implantable—as well as noninvasive—devices for monitoring glucose levels has been happening for many years. Regardless of publicity, the devices will still need to go through rigorous testing before they come to the market. Nevertheless, plasmonic interferometry offers a wide range of opportunities for numerous sensing applications.

Scale of Impact

  • Low
  • Medium
  • High
The scale of impact for this topic is: Medium

Time of Impact

  • Now
  • 5 Years
  • 10 Years
  • 15 Years
The time of impact for this topic is: 15 Years

Opportunitites in the following industry areas:

Medical, environmental, food and drink, defense

Relevant to the following Explorer Technology Areas: