Nano 'cargo ship' searches and destroys tumors

Scientists have built a nanometer-sized 'cargo ship' that can swim throughout the body through the blood stream without being detected by the immune radar system. It transports anticancer drugs to tumors that may not be detected or untreated.

Scientists at UC San Diego, UC Santa Barbara and MIT report that the nano-cargo ship system, incorporating healing and diagnostic functions into a single device, can avoid system rejection. body immunity.

Michael Sailor, UCSD biochemist, who led the team of chemists, biologists and engineers turned the amazing concept into reality, said: 'This idea encapsulates Image and pharmaceutical agents into a 'mother boat' are protected to avoid the natural cycle of removing similar devices if they are not protected. Mother boats have a diameter of 50 nanometers, or 100 times smaller than human hair; and equipped with a number of molecules on the surface that allow them to search and invade y cells in the body. '

These micro cargo ships could one day provide a means to effectively deliver anticancer drugs to tumors without causing harmful effects to other parts of the body.

Sangeeta Bhatia, a physicist and bioengineer and professor of technology and health sciences at MIT, who plays an important research role, said: 'Many types are very promising in the room experiment but not successful on people because they cannot reach the infected tissue in time or the concentration is not high enough to be effective. These types of products are unable to avoid the body's natural defenses or distinguish diseased tissue from healthy tissue. In addition, we lack the tools to diagnose diseases such as cancer at an early stage, the time of treatment is most effective. '

To avoid detection, the researchers designed the hull with specially modified lipids - the basic component of the natural cell surface. These lipids are modified in a way that allows them to circulate in the bloodstream for hours before being excluded. This has been proven by researchers in a series of experiments with mice. The material used to design the hull is strong enough so that the cargo inside does not leak out when circulating in the blood. Attached to the surface of the hull is the F3 protein, which binds to the cancer cell. In the laboratory of Erkki Ruoslahti, cell biologist and professor at Burnham Medical Research Institute at UC Santa Barbara, F3 is designed to attach itself to the surface of tumor cells and gradually move into the nucleus. cell.

Ruoslahti: 'We are building the next generation of smart nano devices. We hope that these devices will improve the diagnosis of cancer by imaging and allow the targeted direction of treatments for cancer tumors. '

A glass jar containing anti-cancer nano ships turns red under black light.The particles turn red because they contain fluorescent fluorescent 'quantum dots'.(Photo: Luo Gu, UCSD).

Researchers loaded their ships with three types of cargo before injecting them into mice.Two types of nanoparticles, superparamagnetic iron oxide and fluorescent quantum dots, were placed in the cargo compartment, along with the cancer drug doxorubicin. Iron oxide nanoparticles allow the ship to appear on a magnet resonance imaging device, or MRI; whereas the self-quantum dot can be observed by another imaging device, the fluorescence scanner. Sailor said: 'The fluorescence image has a higher resolution than MRI. A surgeon can identify the specific location of a tumor in the body before performing an MRI surgery, then use a fluorescence image to find and remove all parts of the tumor in when surgery '. The team was surprised to find that a mother ship could carry multiple iron oxide nanoparticles at the same time and thereby increase the brightness of the MRI image.

"The ability to carry multiple superparamagnetic nanoparticles of these nanostructures makes it easier to observe them on MRI, which means that small tumors can be found," Sailor said . The fact that the ship can contain non-uniform ingredients - a male element, an optical quantum dot, and a drug molecule - is truly amazing. '

The researchers stressed that the construction of a 'hybrid nanotechnology system' contains many different types of nanoparticles studied by many other scientific groups. Although re-creation is used for many laboratory applications outside the living system, Sailor said, however, the number of studies done on living organisms is very limited, especially for treatment. and recording cancer pictures.

He added: 'It is because of the instability and short circulation time in the blood that is often seen in those complex nanostructures' . Therefore, this latest research is special and unique.

Ji-Ho Park, a graduate student at the Sailor Lab, a member of the research team, said: 'The study provides the first example of nanomaterials used to simultaneously deliver drugs and write copy pictures of diseased tissue in living organisms' . Geoffrey von Maltzahn, a graduate student working at Bhatia's lab, also participated in this project. National Academy of Cancer and Academy of Health sponsors research.

The nano-vessel looks like a chocolate-covered nut cluster in which biocompatible lipids form a crust of chocolate; Magnet nanoparticles, quantum dots and doxorubicin are nuts. They swim in the bloodstream and under the electron microscope tube, which looks like little pearl strands broken.

Researchers are developing methods to attach to the outer layer of the specific nano 'chemical code' ship, allowing them to transmit to certain tumors, organs or parts of the body.

Refer:

Ji-Ho Park et al.Micellar Hybrid Nanoparticles for Simultaneous Magnetofluorescent Imaging and Drug Delivery.Angewandte Chemie International Edition, Volume 47 Issue 38, Pages 7284 - 7288 DOI: 10.1002 / anie.200801810