Transcript note 4b

nanobiotechnology
&
bionanotechnology
Intro
• Two of most promising technologies of future:
– Biotechnology: Use of living in the creation of wealth (products
or processes)
– Nanotechnology: creation, investigation and utilisation of
systems that are 1000 times smaller than the components
currently used in the field of microelectronics.
• The interface of these two worlds lies Nanobiotechnology
– It uses nanotechnology to analyse and create biological
nanosystems
– It uses biological materials and structural plans to produce
technical, functional nanosystems
Intro
• Functional biological assemblies are inspiration for
nanotechnological systems and devices
• Molecular recognition btw. building blocks
self-assembly
formation of functional devices
• motors, pumps, cables, etc, all functioning at the nano-scale
What we should know and what are the
possibilities??
• Interaction between biological and non-biological devices???
– Interactions with biological as well as non-biological substrates
– Toxicity
– How does nature make use of adhesive and anti-adhesive interactions?
• Screening methods in biology
– Bio-Chips
– Lab-on-a-chip
• Nanotechnologically modified biomaterials
– Nano aspects of biological systems
– Nanotechnological tools to improve biomaterials
• Nanoparticles as therapeutic drug carriers and diagnostics
– Drug, oligonucleotide, imaging agents
• Nanodevices in medicine, pharmacy and biology
Bionano-DNA as template
Gazid E., FEBS Journal, 2006
DNA is very suitable for nanotechnological applications from the
material science point of view:
1.
The diameter of ssDNA is less than 1 nm
2.
DNA molecules are chemically very robust
3.
Low cost of large-scale chemical DNA synthesis
4.
Easy modification: for example, by biotinylation or thiolation
Bionano-DNA as template
Gazid E., FEBS Journal, 2006
Examples:
• DNA used in the formation of nanowires (1998): Metallization of
dsDNA btw two gold electrodes to form conductive silver nanowire
• DNA-binding proteins (Figure)
DNA Codes for Nanoscience
a)
b)
c)
d)
Holliday junction
Assembly of gold nanoparticles
Immobilization of gold NP
PCR mediated introduction of new
fuctionalities to create DNAprotein hybrids
e) Self-replication of connectivity
Inspired by Nature-1
Yusko, E.C et. al, Nature Nanotechnology, 6:253–260, 2011
Challenges to reach the full potential of nanopore-based sensing:
• reliable fabrication of synthetic nanopores on the sub-nanometre
scale
• better control of translocation times of single-molecule analytes
• methods to control the surface chemistry inside synthetic pores:
reduce non-specific interactions of analytes with the pore walls and
prevent pore clogging
• low frequency of translocation events at low analyte concentrations
and the poor specificity of the nanopores for analytes need to be
improved
Inspired by Nature-2
Yusko, E.C et. al, Nature Nanotechnology, 6:253–260, 2011
Fig 1: Insects detect pheromones by
translocating odorant molecules
through lipid-coated nanopores (D:
6–65 nm)
Fig 2: Lipid coatings are thought to
participate in the capture, preconcentration and subsequent
translocation of odorants to specific
receptors
Fig 3: Capture, affinity-dependent
pre-concentration and translocation
of specific proteins after binding to
ligands on mobile lipid anchors
Inspired by Nature-3
Yusko, E.C et. al, Nature Nanotechnology, 6:253–260, 2011
• Clogging Problem: Amyloidogenic peptides: e.g.
Alzheimer's disease-related amyloid-beta (Aβ) peptides
Self-Assembly of a Viral Molecular
Machine from Purified Protein and RNA
Constituents
Poranen et al, Molecular Cell, Vol. 7, 845–854,
2001
• Understanding of self-assembly in
nature…
Cellular imaging
in Cell
Cell tracking: Different
population of cells in
tissue
in Cell
in Cell
Photo-thermal therapy
in Cell
MRI and Cell Tracking
 Fate of cells in the implanted
area
Anticancer therapy
in Cell
Nanotech in Drug Delivery
• Controlled drug-delivery systems deliver drugs in the optimum
dosage for long periods
– increasing the efficacy of the drug
– maximizing patient comfort
– enhancing the ability to use highly toxic, poorly soluble or relatively
unstable drugs
• Nanoscale materials can be used as drug delivery vehicles to
develop highly selective and effective therapeutic and diagnostic
systems
• Nano vs micro
– nanoscale particles can travel through the blood stream without
sedimentation or blockage of the microvasculature
– Small nanoparticles can circulate in the body and penetrate tissues
– nanoparticles can be taken up by the cells through natural means such
as endocytosis
Nanotech in Drug Delivery
•
•
•
Particle Size, Surface-to-Volume Ratio, Surface Area, and Surface Free
Energy
Biological Reactivity
Opsonisation: thought to be the greatest threat
engulfment of foreign
particles injected into the blood stream by specific macrophages cells of
RES (reticulo endothelial system)
Modifications:
• Nonadhesive surface coatings
• Attachment of molecules for targetting
• Layer-by-layer methods: shown to regulate nanoparticle biodistribution:
cationic pegylated liposomes are preferantially uptaken by the liver and
tumor vessels in stead of spleen and blood accumulation
• Synthesis from amphiphilic polymers
Nano-Layered Microneedles for Transcutaneous Delivery of Polymer
Nanoparticles and Plasmid DNA
DeMuth et al, 2010, Advanced Materials
Luciferase gene and lipid-coated
PLGA NPs were delivered
seperately.
A) SEM micrograph of uncoated
PLGA microneedle arrays
B) Polyelectrolyte layers
A)
B)
C)
D)
24 bilayers for 5 min
1 bilayer for 24 h
5 bilayers for 24 h
24 bilayers for 24 h
Nanoparticles for ex vivo siRNA delivery to dendritic cells for cancer
vaccines: Programmed endosomal escape and dissociation
Akita et al (2010) and Kogure et al (2007) J. Cont. Rel
Solution??
• Programmed packaging
Targeted PLGA nano- but not microparticles specifically
deliver antigen to human dendritic cells via DC-SIGN in vitro
Cruz et al (2010), J. Cont. Rel.
• Specific targeting of NPs to human
DCs enhances antigen presentation
Nanotech in Medicine: Oncology
• It can complement existing technologies for detection,
prevention, diagnosis and treatment
• Useful in the area of biomarker research and increase
sensitivity in assays with relatively small sample volume
Jain, KK, BMC Medicine 2010, 8:83
Nanotech in Tissue Engineering
• For proper function and organization, we should
mimic native tissues at the nanoscale
– Fabrication: top-down, bottom-up
– Modification: Microfabrication and nanofabrication to
modify surface properties with resolutions as small as
50 nm
control of cell behavior, orienting cells and
guiding cell migration, differentiation??
Cell interactions with hierarchically structured nanopatterned adhesive surfaces
Arnold, M, et al, Soft Matter, 2009, 5, 72
• Counting the number of clustering cell adhesion based
transmembrane proteins is performed by molecular
defined, biofunctionalised nanopatterns of defined single
protein binding sites confined in micrometre large areas,
i.e. hierarchically organised micro-nanopattern
Nanotech in Bio-Sensing
Nanotech in Medicine: AMPs
Review: Calderon et al, Amino Acids (2011) 40:29–49
• Cationic nanoparticles formed by the conjugation of
cholesterol and antimicrobial peptides (AMPs): to
cross the blood–brain barrier for treatment of fatal
Cryptococcal (Wang et al. Biomaterials 31(10):2874–
2881 2010)
• Nanostructured thin films with immobilized AMPs as
an agent intended to combat and prevent infection and
formation of Staphylococcus biofilm related implant
failure (Shukla et al. Biomaterials 31(8):2348–2357,
2009)
Interface: NSA-1
1. Park, S; Hamad-Schifferli, K, Current Opinion in Chemical Biology, 14: 616622, 2010
2. You, et al, Nano Today 2 (2007), 34–43
3. Park and K. Hamad-Schifferli, ACS Nano 4 (2010), 2555–2560
• The biological behavior of nanomaterials depends primarily on how
they interface to biomolecules and their surroundings
• Issues like non-specific adsorption (NSA) are still the biggest
obstacles and have held back widespread practical use of
nanotechnology in biology
Interface: NSA-2
Utilizing NSA:
(a) Tunable intracellular release from
NP–DNA ‘nanoplexes’
(b) Enhancing protein translation: In
vitro gene expression with DNA,
AuNP recruits mRNA and
translation related molecules into
its proximity
(c) Protein coronas induce a
biological response
Nanonetworks
Communication???
•
•
•
•
Nanomechanical
Acoustical
Electromagnetic
Chemical or Molecular
Short-range:
• Molecular motors
• Ca2+ signalling
Long-range:
• Pheromones