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Stimuli-responsive controlled-release system using quadruplex DNA-capped silica nanocontainers.

Chen C, Pu F, Huang Z, Liu Z, Ren J, Qu X - Nucleic Acids Res. (2010)

Bottom Line: Start from simple conformation changes, the i-motif DNA cap can open and close the pore system in smart response to pH stimulus.A pH-switchable nanoreactor has also been developed to validate the potential of our system for on-demand molecular transport.This proof of concept might open the door to a new generation of carrier materials and could also provide a general route to use other functional nucleic acids/peptide nucleic acids as capping agents in the fields of versatile controlled delivery nanodevices.

View Article: PubMed Central - PubMed

Affiliation: Laboratory of Chemical Biology and State Key laboratory of Rare Earth Resources Utilization, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun, 130022, PR China.

ABSTRACT
A novel proton-fueled molecular gate-like delivery system has been constructed for controlled cargo release using i-motif quadruplex DNA as caps onto pore outlets of mesoporous silica nanoparticles. Start from simple conformation changes, the i-motif DNA cap can open and close the pore system in smart response to pH stimulus. Importantly, the opening/closing and delivery protocol is highly reversible and a partial cargo delivery can be easily controlled at will. A pH-switchable nanoreactor has also been developed to validate the potential of our system for on-demand molecular transport. This proof of concept might open the door to a new generation of carrier materials and could also provide a general route to use other functional nucleic acids/peptide nucleic acids as capping agents in the fields of versatile controlled delivery nanodevices.

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Schematic representation of proton-fueled release of guest molecules from the pores of MSN capped with i-motif DNA.
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Figure 1: Schematic representation of proton-fueled release of guest molecules from the pores of MSN capped with i-motif DNA.

Mentions: An i-motif DNA which carries a piece of the human telomeric sequence was attached on the exterior of MCM-41 particles as a model system in this work. I-Motif DNA is a four-stranded DNA structure with stretches of cytosine base (20). It undergoes a precise structural change driven by a pH change with significant force (8–10 pN) (5,21–22). We then sought to take advantage of this unique feature to control the gate operation. The working principle of the system is illustrated in Figure 1. At low pH, the C residues are partially protonated and the DNA folds into the closed i-motif structure, the pores are capped by the quadruplex and the release of the cargo is strongly inhibited. When the pH is increased to basic, the C+ residues are deprotonated and the DNA unfolds to a single-stranded form, the silica nanopores are spontaneously unblocked which results in rapid delivery of the cargo from the pore voids into the aqueous solution. Thus, the interconversional cycles of the closed and open states of the gated system could be demonstrated by measuring the pH-dependent release of the loaded dye molecules.Figure 1.


Stimuli-responsive controlled-release system using quadruplex DNA-capped silica nanocontainers.

Chen C, Pu F, Huang Z, Liu Z, Ren J, Qu X - Nucleic Acids Res. (2010)

Schematic representation of proton-fueled release of guest molecules from the pores of MSN capped with i-motif DNA.
© Copyright Policy - creative-commons
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC3045591&req=5

Figure 1: Schematic representation of proton-fueled release of guest molecules from the pores of MSN capped with i-motif DNA.
Mentions: An i-motif DNA which carries a piece of the human telomeric sequence was attached on the exterior of MCM-41 particles as a model system in this work. I-Motif DNA is a four-stranded DNA structure with stretches of cytosine base (20). It undergoes a precise structural change driven by a pH change with significant force (8–10 pN) (5,21–22). We then sought to take advantage of this unique feature to control the gate operation. The working principle of the system is illustrated in Figure 1. At low pH, the C residues are partially protonated and the DNA folds into the closed i-motif structure, the pores are capped by the quadruplex and the release of the cargo is strongly inhibited. When the pH is increased to basic, the C+ residues are deprotonated and the DNA unfolds to a single-stranded form, the silica nanopores are spontaneously unblocked which results in rapid delivery of the cargo from the pore voids into the aqueous solution. Thus, the interconversional cycles of the closed and open states of the gated system could be demonstrated by measuring the pH-dependent release of the loaded dye molecules.Figure 1.

Bottom Line: Start from simple conformation changes, the i-motif DNA cap can open and close the pore system in smart response to pH stimulus.A pH-switchable nanoreactor has also been developed to validate the potential of our system for on-demand molecular transport.This proof of concept might open the door to a new generation of carrier materials and could also provide a general route to use other functional nucleic acids/peptide nucleic acids as capping agents in the fields of versatile controlled delivery nanodevices.

View Article: PubMed Central - PubMed

Affiliation: Laboratory of Chemical Biology and State Key laboratory of Rare Earth Resources Utilization, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun, 130022, PR China.

ABSTRACT
A novel proton-fueled molecular gate-like delivery system has been constructed for controlled cargo release using i-motif quadruplex DNA as caps onto pore outlets of mesoporous silica nanoparticles. Start from simple conformation changes, the i-motif DNA cap can open and close the pore system in smart response to pH stimulus. Importantly, the opening/closing and delivery protocol is highly reversible and a partial cargo delivery can be easily controlled at will. A pH-switchable nanoreactor has also been developed to validate the potential of our system for on-demand molecular transport. This proof of concept might open the door to a new generation of carrier materials and could also provide a general route to use other functional nucleic acids/peptide nucleic acids as capping agents in the fields of versatile controlled delivery nanodevices.

Show MeSH
Related in: MedlinePlus