Gene delivery, polyion complex

Keywords Biocompatibility Biosignal sensitivity Gene delivery Nonviral carriers Oligodeoxynucleotide (ODN) delivery Polyion complex (PIC) micelle Polymeric carriers siRNA dehvery... 

Figure 5 The PIC (polyion complex) micelles from varying block polycations and DNA for delivery of genes.

Scaffolds can also be used for the delivery of genes. Kido et al. prepared scaffolds of gelatin and (3-tricalcium phosphate ((3-TCP) to search their gene transfection capabilities. The scaffolds were loaded with a spermine-pullulan luciferase plasmid DNA polyion complex and then stem cells were seeded into the scaffolds. It was shown that the level of plasmid DNA transfection was dependent on the method of the scaffold preparation. ... 

PEG-polyelectrolyte block polymers were also found to form polyion complex (PIC) micelles with negatively charged DNA through electrostatic interactions. This is particularity important in the field of gene and DNA/ RNA delivery, as the PIC micelles exhibit an excellent... 

PECs are the association complexes mainly formed between oppositely charged particles (e.g., polymer-polymer, polymer-drug, polymer-surfactant, polymer-protein). These complexes are formed due to electrostatic interaction between oppositely charged polyions. This interaction avoids the use of chemical cross-linking agents that can reduce the possible toxicity and other undesirable effects of the reagents. The PECs formed between a poly acid and poly base are less affected by the pH variation of the dissolution medium. The complexation, between DNA and chitosan, has been extensively studied in the development of delivery vehicle for gene therapy and oral vaccination. 

The physicochemical behavior of the PECs was studied at low polyion concentrations that were in the range generally used in the case of the administration of macromolecular prodrugs or of complexes for drug delivery via nanodispersed amphiphilic systems and gene transfection (11-13). 

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