Bionanomachines

Why BIO nanomachines?

• Challenge : Enduring nanoassemblies • Bio approach: Self-organization and bioengineering

Any disadvantages of using bionanomachines?• communication between classical microsystems (in

particular electronic systems) and the nanoscaled biomolecules

• Biomaterials are less stable than organic and semiconductor structures

Protein based bionanomachines

• Motor proteins : Myosine, Kinesin, Microtubules, dynein,

• Molecular motor assemblies: flagellar motor, ATPase, Polymerase etc.

• Synthetic protein based nanomachines: – Molecular motors – Molecular propellers – Molecular switch – Molecular tweezers– Molecular receptors and recognition system – Molecular logic gates

Nucleic acid based nanomaterial

• Principle of DNA nanotechnology : specific base pairing

• Different DNA structures used:– Periodic lattices– DNA nanotubes – Polyhedra

Double-crossover

• Application of DNA nanotechnology– DNA machines – Molecular recognition – Nano medinces

MOLECULAR MOTORS

• The integration of biomolecular motors with nanoscale engineered systems enables the development of hybrid organic-inorganic devices capable of using ATP as an energy source.

Functionalization of Nanoparticles

• Why? – For targeted drug/gene delivery – For specific bio-images – For specific detection

• Approach :– Bioconjugation: Bioconjugation can be described as any

procedure that links a nanoparticle to a biomolecule under mild conditions

– Biocompatible coating :• Prevention of nanoparticle aggregation in a biological environment,• Effective suppression of non-specific adsorption of biomolecules at the

nanoparticle surface or their accumulation close to the surface• Low cytotoxicity

A, Physisorption of biomoleculesB, Assisted physisorptionC, Using linker moleculeD, Direct chemical coupling E, Targeted binding of biotinylated biomolecules to streptavidincoated nanoparticles via biotin–streptavidin coupling

• Different groups used for Nanoparticle-stabilizing Coatings– PEG : Flu. Nanoparticles– BSA: Flu. Nanoparticles– Oligo or polypeptides: metallic nanoparticles – Oligonucleotides: metallic nanoparticles – Antisense or sense RNA molecules : DNA NP– Antibodies: Core shells – Cell surface receptors : Core shells

• Low Cytotoxicity Coatings– They will reduce the oxidation potential of highly

reactive quantum dots

Functionalization • PEGylation: – GNPs are coated with a layer of PEG alone or in

conjunction with other molecules such as biotin, peptides or oligonucleotides, thereby helping the internalization of these GNPs to the target cells.

• Peptide/Amino Acid Conjugation: – GNPs functionalized with amino acids such as lysine,

polylysine and glycine bind DNA with higher efficiency for gene delivery without toxicity.

– GNPs functionalized with peptides are used as effective cell-targeting agents.

– Peptide functionalized GNPs are also activate macrophages, holding promise to be used as adjuvants for vaccine delivery

– Bioconjugated GNPs are used as probes for imaging

• Oligonucleotide Functionalized Nanoparticles:– Aptamer-GNP conjugation are used to target

cancer cells– DNA functionalized GNPs were employed to

design a chip based DNA bio bar code sensor• Antibody Functionalized Nanoparticles– For biosensor studies

Viral Based nanoparticles

• Virus are used to organize nanoparticle in supra-molecular architecture

• Template mineralization: Wild-type and recombinant tobacco mosaic virus (TMV) hollow cylinders have been used as templates to generate inorganic-organic nano-tube composites