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Lego-like gene delivery system is child's play
12 May 2010
Functionalised gold nanoparticles make a more efficient and versatile delivery system for use in gene therapy and cancer treatment, claim Korean scientists.
Gold nanoparticles are non-toxic and easily made and so provide an effective way to deliver therapeutic antisense DNA to disease causing genes. Antisense DNA that is covalently attached to the nanoparticles will bind to messenger RNA of a disease causing gene, preventing translation and therefore inactivating it. But previous systems could deliver only antisense DNA that was covalently cross-linked to gold nanoparticles, which needed to be individually synthesized for each gene of interest.
Now, Kangseok Lee and Min Su Han at Chung Ang University, Seoul along with colleagues at CHA University, Seongnam, demonstrate a new method which enables any DNA sequence to be attached to one core particle allowing easier and more versatile gene targeting and delivery. The team functionalised their nanoparticles with an oligonucleotide bearing a partial sequence of RNA I, which is involved in the replication of ColE1-type plasmid in Escherichia coli. Human cells do not contain nucleic acids complementary to the sequence of RNA I oligonucleotide therefore it won't interfere with expression of any human genes, explain Han and Lee. Antisense DNA specific to any gene of interest can be picked up by the olignucleotide and loaded onto the functionalised nanoparticles.
Antisense DNA specific to any gene of interest is picked up and delivered by the nanoparticles
Vincent Rotello, an expert in supramolecular chemistry and nanodelivery agents at the University of Massachusetts in Amherst, US, is impressed with this new system. 'This approach is lego-like, allowing any DNA sequence to be plugged into a single particle scaffold, providing an incredibly versatile delivery system,' he says. 'It presents a very clever supramolecular approach to creating an effective antisense delivery vehicle.'
'This method can be used for many therapeutic purposes such as tumour regression and gene therapy in living organisms that include humans and animals,' says Lee. Han and Lee also hope to move the project forward so that gene expression in the nucleus can be regulated. 'We think that the development of an efficient gene delivery system for regulating the activities of RNA and DNA in the nucleus is challenging work,' Lee concludes.
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Link to journal article
A functionalized gold nanoparticles-assisted universal carrier for antisense DNA
Jae-Hong Kim, Hyun Hye Jang, Sang-Mi Ryou, Sudeok Kim, Jeehyeon Bae, Kangseok Lee and Min Su Han, Chem. Commun., 2010, 46, 4151
Also of interest
UK chemists have used smart polymers to deliver DNA into cells.
Researchers' dreams of automated gene synthesis could soon become a reality, predict Jingdong Tian and colleagues