Features | Partner Sites | Information | LinkXpress
Sign In
GLOBETECH PUBLISHING
JIB
GLOBETECH PUBLISHING

Nanoparticles Designed to Deliver Drugs to Targeted Cells

By BiotechDaily International staff writers
Posted on 16 Jul 2014
Image: The nanoparticles, which are capable of delivering and exchanging complementary molecules, emit a fluorescent signal that can be observed with a microscope (Photo courtesy of the University of Miami).
Image: The nanoparticles, which are capable of delivering and exchanging complementary molecules, emit a fluorescent signal that can be observed with a microscope (Photo courtesy of the University of Miami).
Investigators are exploring the use and behavior of nanoparticles to deliver molecules to target cells.

There is a great demand for the development of nanoparticles that can transport and deliver drugs to target cells in the human body. Researchers from the University of Miami (UM; Coral Gables, USA) have created nanoparticles that, under favorable settings, can self-assemble, ensnaring complementary guest molecules within their structure. These adaptable nanocarriers can travel in the aqueous environment encircling cells and transport their passenger molecules through the membrane of living cells to sequentially deliver their payload.

Although the transport of molecules inside cells with nanoparticles has been earlier achieved using various methods, researchers have developed nanoparticles capable of delivering and exchanging complementary molecules. For practical applications, these nanocarriers are highly desirable, reported Francisco Raymo, professor of chemistry in the University of Miami College of Arts and Sciences and lead investigator of the project. “The ability to deliver distinct species inside cells independently and force them to interact, exclusively in the intracellular environment, can evolve into a valuable strategy to activate drugs inside cells,” said Prof. Raymo.

The new nanocarriers are 15 nm in diameter. They are supramolecular constructs comprised of amphiphilic polymers. These nanocarriers hold the guest molecules within the boundaries of their water-insoluble core and use their water-soluble exterior to move through an aqueous environment. As a result, these nanovehicles are is suitable for transferring molecules, which would otherwise be insoluble in water, across a liquid environment.

“Once inside a living cell, the particles mix and exchange their cargo. This interaction enables the energy transfer between the internalized molecules,” said Prof. Raymo, director of UM’s laboratory for molecular photonics. “If the complementary energy donors and acceptors are loaded separately and sequentially, the transfer of energy between them occurs exclusively within the intracellular space. As the energy transfer takes place, the acceptors emit a fluorescent signal that can be observed with a microscope.”

Crucial for this process are the noncovalent bonds that loosely hold the supramolecular constructs together. These weak bonds exist between molecules with complementary shapes and electronic characteristics. They are responsible for the ability of supramolecules to assemble spontaneously in liquid environments. Under the right conditions, the reversibility of these weak noncovalent contacts allows the supramolecular constructs to exchange their components as well as their cargo.

The research was conducted with cell cultures. It is not yet known if the nanoparticles can actually travel through the bloodstream. “That would be the dream, but we have no evidence that they can actually do so,” said Prof. Raymo. “However, this is the direction we are heading.”

The next step of this study involves demonstrating that this method can be used to do chemical reactions inside cells, instead of energy transfers. “The size of these nanoparticles, their dynamic character, and the fact that the reactions take place under normal biological conditions [at ambient temperature and neutral environment] makes these nanoparticles an ideal vehicle for the controlled activation of therapeutics directly inside the cells,” Prof. Raymo concluded.

The study’s findings were published in the Journal of the American Chemical Society.

Related Links:

University of Miami



comments powered by Disqus

Channels

Genomics/Proteomics

view channel
Image: Diagram illustrates the innovative process that could lead to more effective drugs against influenza infection (Photo courtesy of the Hebrew University of Jerusalem).

Researchers Show How the Influenza Virus Blocks Natural Killer Cell Recognition

A team of molecular virologists has described how the influenza virus evolved a defense mechanism to protect it from attack by the immune system's natural killer (NK) cells. The recognition of pathogen-infected... Read more

Drug Discovery

view channel
Image: Synthetic ion transporters can induce apoptosis by facilitating chloride anion transport into cells (Photo courtesy of the University of Texas, Austin).

Experimental Drug Kills Cancer Cells by Interfering with Their Ion Transport Mechanism

An experimental anticancer drug induces cells to enter a molecular pathway leading to apoptosis by skewing their ion transport systems to greatly favor the influx of chloride anions. To promote development... Read more

Therapeutics

view channel
Image: Liver cells regenerated in mice treated with a new drug (right) compared with a control group (center) after partial liver removal. Healthy liver cells are shown at left (Photo courtesy of Marshall et al, 2014, the Journal of Experimental Medicine).

New Drug Triggers Liver Regeneration After Surgery

Investigators have revealed that an innovative complement inhibitor decreases complement-mediated liver cell death, and actually stimulates postsurgery liver regrowth in mice. Liver cancer often results... Read more

Business

view channel

Partnership Established to Decode Bowel Disease

23andMe (Mountain View, CA,USA), a personal genetics company, is collaborating with Pfizer, Inc. (New York, NY, USA), in which the companies will seek to enroll 10,000 people with inflammatory bowel disease (IBD) in a research project designed to explore the genetic factors associated with the onset, progression, severity,... Read more
 
Copyright © 2000-2014 Globetech Media. All rights reserved.