Nanotechnology Now - Press Release: Nanorod-Aptamer Combo Targets Tumors

Home > Press > Nanorod-Aptamer Combo Targets Tumors

Abstract:
Aptamers, short stretches of DNA or RNA that can act much like antibodies, have shown promise as targeting agents for selective nanoparticle trafficking to tumors. Their ability to recognize and bind to tumor-specific molecules is undisputed, but the strength with which aptamers bind to their molecular targets is often insufficient to act as an effective targeting agent under clinically relevant conditions.

Nanorod-Aptamer Combo Targets Tumors

Bethesda , MD | Posted on January 16th, 2008

Now, a research team headed by Weihong Tan, Ph.D., at the University of Florida has shown that adding up to 80 aptamers on a single gold/silver nanorod increases the binding ability of this construct by at least 26-fold compared with that of an individual aptamer. Using dye-labeled aptamers, the investigators also were able to produce a cancer-detecting probe whose fluorescent signal is more than 300 times greater than that produced by individual dye-labeled aptamers. This work was published in the journal Analytical Chemistry.

In earlier work, Tan and his colleagues had shown that aptamer-labeled magnetic nanoparticles could be used to separate cancer cells from a mixture of normal and malignant cells. In the current study, he and his colleagues have extended the utility of aptamer targeting by demonstrating that multiple copies of an aptamer, when distributed along the surface of a nanorod, dramatically increase the binding affinity of the nanoscale construct through cooperative binding.

Cooperative binding works in much the same way as the multiple hooks and loops on Velcro®. If the interaction between one hook and loop, or one aptamer and its cellular target, is disrupted, other binding pairs maintain the connection between the two objects, whether it be the nanorod and cancerous cell or the two halves of a Velcro® pair. These findings, the investigators note, suggest that even aptamers that bind weakly, but specifically, to a cancer-related target could still prove useful as nanoparticle targeting agents. Indeed, the use of multiple weak-binding aptamers could reduce nonspecific binding of targeted nanoparticles or nanorods to healthy cells.

This work, which was supported in part by the NCI, is detailed in the paper "Cancer cell targeting using multiple aptamers conjugated on nanorods." An investigator from National Taiwan University in Taipei, Taiwan, also participated in this study. An abstract of this paper is available through PubMed.

####

About National Cancer Institute
To help meet the goal of reducing the burden of cancer, the National Cancer Institute (NCI), part of the National Institutes of Health, is engaged in efforts to harness the power of nanotechnology to radically change the way we diagnose, treat and prevent cancer.

The NCI Alliance for Nanotechnology in Cancer is a comprehensive, systematized initiative encompassing the public and private sectors, designed to accelerate the application of the best capabilities of nanotechnology to cancer.

Currently, scientists are limited in their ability to turn promising molecular discoveries into benefits for cancer patients. Nanotechnology can provide the technical power and tools that will enable those developing new diagnostics, therapeutics, and preventives to keep pace with today’s explosion in knowledge.

For more information, please click here

Contacts:
National Cancer Institute
Office of Technology & Industrial Relations
ATTN: NCI Alliance for Nanotechnology in Cancer
Building 31, Room 10A49
31 Center Drive , MSC 2580
Bethesda , MD 20892-2580

If you have a comment, please Contact us.

Issuers of news releases, not 7th Wave, Inc. or Nanotechnology Now, are solely responsible for the accuracy of the content.

Bookmark: