Polymer-nucleic acid conjugates

Recently, many other examples of well-defined drug- and nucleic acid-conjugated ROMP polymers have also been reported [86-89]. 

Xu H, Wu HP, Huang F, Song SP, Li WX, Cao Y, Fan CH (2005) Magnetically assisted DNA assays high selectivity using conjugated polymers for amplified fluorescent transduction. Nucleic Acids Res 33 e83... 

Functional Polymer Conjugates for Medicinal Nucleic Acid Delivery... 

Other systems like electroporation have no lipids that might help in membrane sealing or fusion for direct transfer of the nucleic acid across membranes they have to generate transient pores, a process where efficiency is usually directly correlated with membrane destruction and cytotoxicity. Alternatively, like for the majority of polymer-based polyplexes, cellular uptake proceeds by clathrin- or caveolin-dependent and related endocytic pathways [152-156]. The polyplexes end up inside endosomes, and the membrane disruption happens in intracellular vesicles. It is noteworthy that several observed uptake processes may not be functional in delivery of bioactive material. Subsequent intracellular obstacles may render a specific pathway into a dead end [151, 154, 156]. With time, endosomal vesicles become slightly acidic (pH 5-6) and finally fuse with and mature into lysosomes. Therefore, polyplexes have to escape into the cytosol to avoid the nucleic acid-degrading lysosomal environment, and to deliver the therapeutic nucleic acid to the active site. Either the carrier polymer or a conjugated endosomolytic domain has to mediate this process [157], which involves local lipid membrane perturbation. Such a lipid membrane interaction could be a toxic event if occurring at the cell surface or mitochondrial membrane. Thus, polymers that show an endosome-specific membrane activity are favorable. 

Gaylord BS, Massie MR, Feinstein SC, Bazan GC (2005) SNP detection using peptide nucleic acid probes and conjugated polymers applications in neurodegenerative disease identification. Proc Natl Acad Sci USA 102 34—39... 

Gaylord BS, Heeger AJ, Bazan GC (2002) DNA detection using water-soluble conjugated polymers and peptide nucleic acid probes. Proc Natl Acad Sci USA 99 10954—10957... 

Hameed AAA, Jean N, Stephen O, Andy PM (2008) Improved single nucleotide polymorphisms detection using conjugated polymer/surfactant system and peptide nucleic acid. Biosens Bioelectron 23 1466-1472... 

Another coupling method, i.e. cross-linking or entrapment in polymeric films, which has been used to create a more permanent nucleic acid surface, is described in some chapters (e.g. conductive electroactive polymers for DNA immobilization and self-assembly DNA-conjugated polymers). One chapter reviews the basic characteristics of the biotin-(strept)avidin system laying the emphasis on nucleic acids apphcations. The biotin-(strept)avidin system can be also used for rapid prototyping to test a large number of protocols and... 

The chemical modification of nucleic acids at specific sites within individual nucleotides or within oligonucleotides allows various labels to be incorporated into DNA or RNA polymers. This labeling process can produce conjugates having sensitive detec-... 

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