Between each PEG ligand, molecules of a photodynamic chemotherapy drug (Pc 4) are attached to the Au NP. The Pc 4 drug (a phthalocyanine compound) was developed at Case Western Reserve by Malcolm Kenney, professor of chemistry.
When the nanoparticle reaches the cancerous tissue the drug molecules are released and uploaded to the diseased area. Focused red light is used to energize the drug in the patient once it has been delivered to the tumor.
Burda says that a potential future research project would look at providing a time-release administration of the drug rather than a more all-at-once release. In the long term, Burda hopes to make the Au NP delivery system applicable to a broad range of diseases.
The Au NP has a diameter of 5 nm. The addition of PEG ligands expands the total diameter to 32 nm, larger than some other nanoparticles currently in use, but still small enough to pass unencumbered through the bloodstream.
A single 1/4-mL injection holds approximately 100 million Au NPs, each carrying approximately 100 drug molecules.
Tail to Tumor in Two Minutes
In the laboratory of Baowei Fei, assistant professor of radiology and biomedical engineering at Case Western Reserve, these Au NPs have been used to treat mice with cancerous tumors. Once the Au NPs have been injected into the tail, the Pc 4 is uploading into the diseased area within minutes. The accelerated speed of drug administration in mice is due in part to the much more efficient dispersion of the NP delivered drug.
When tested on human cells called HeLa a line of laboratory-grown human cells used in testing most of the dru
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Case Western Reserve University