nanotechnology applications for treatment: cost effective and rapid technologies; smart materials or...
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Why Nanomaterials? Ability to manipulate, control and build materials at the atomic and molecular level Provide novel affinity, capacity, and selectivity because of their unique physical, chemical and biological properties. Create large structures with new molecular organization that will facilitate recoveryTRANSCRIPT
NANOTECHNOLOGY APPLICATIONS FOR TREATMENT: COST EFFECTIVE AND
RAPID TECHNOLOGIES; SMART MATERIALS OR ACTIVE SURFACE COATINGS
Wilfred Chen Chemical and Environmental Engineering University of
California, Riverside Why Nanomaterials? Ability to manipulate,
control and build materials at the atomic and molecular level
Provide novel affinity, capacity, and selectivity because of their
unique physical, chemical and biological properties. Create large
structures with new molecular organization that will facilitate
recovery Types of Nanomaterials for Environmental Treatments
1. Smart modified surfaces or membranes 2. Nanostructured materials
3. Molecularly imprinted polymers 4. Nanoscale Biopolymers Smart
Surfaces or Membranes Active Membranes for Heavy Metal Removal
Types of modifying peptides
poly-L-glutamateor aspartate poly-L-lysine or arginine
poly-L-cysteine Ritche et al. ES&T 2001 Metal Chelating
Behavior
poly-L-lysine or arginine - oxyanion such as As Results with
poly-cysteine membrane
The temperature profile for turbidity formation was used to measure
the onset of folding and aggregation of the biopolymers. The value
of Tt, which is defined as the temperature at which 50% turbidity
occurred, was used to indicate the phase transition properties of
the different biopolymers. Tunable Surfaces for Biofouling
Ista et al. Appl. Environ. Microbiol. 1999 Nanostructured Materials
Poly(amidoamine) Dendrimers
Diallo et al. ES&T 1999 Binding properties Repeating cycles of
metal binding with Ela78H12 biopolymers. Five microgram of cadmium
were added in each cycle.S: Cd2+ remained in solution; P: Cd2+
removed by biopolymers; AS: Average amount of Cd2+ remained in
biopolymers after stripping. Polymeric Nanoparticles
Tungittiplakorn et al. Appl. Environ. Microbiol. 2004 Enhance PAH
Desorption Amphiphilic Polyurethane Nanoparticles
Kim et al. Journal of Applied Polymer Science 2004 90 nm in size
Enhanced PAH Solubility PHEMA Beads containing
N-Methacryloylhistidine
Say et al. Macromol. Mater. Eng. 2002 Metal Removal Molecularly
Imprinted Polymers Atrazine-Imprinted Polymers
Cacho et al. Anal Bioanal Chem 2002 Imprinted Polymers for Virus
Removal
Infection Frequency of Spodoptera frugiperda 9 (Sf9) cells 0% 10%
20% 30% 40% 50% 60% 70% 80% 90% 100% 6.89E+05 6.89E+04 6.89E+03
6.89E+02 Dilution (pfu/mL) Reactive Polymer Hydrogel for Phosphate
Removal
Kiofinas et al. ES&T 2003 Efficiency of Removal Perchlorate
Removal Kioussis et al. Journal of Applied Polymer Science 2001
Efficiency of Removal Tunable Biopolymer with Metal-Binding
Property
Elastin DomainMetal Binding Domain Fine tune affinity with
different binding sequence Fine tune DT by controlling amino acid
sequence and no. of repeating unit (VPGXG)n Genetic and Protein
Engineering Methodology
Synthetic gene Recombinant plasmid Plasmid Enzyme ELP biopolymers
Microbial expressions of artificial genes provides a means of
easily producing ELP. amino acid sequences are chosen to create
specific folding patterns and desired material properties. The
primary amino acid sequence can then be reverse-translated into a
corresponding nucleotide sequence. There are 2 methods of obtaining
the needed DNA fragments. One possibility is to clone these
sequences from an organism that produces the desired structural
protein. The second option is to synthesize artificial genes by
solid phase techniques. The second method of course allows maximum
freedom in designing the target sequence. Because many structural
proteins are characterized by repetitive amino acid sequences, it
is often possible to multimerize a smaller oligonucleotide sequence
to prepare an artificial gene that codes for proteins of high
molecular weight. Metal Removal Recycling DT Cd2+ + Cd2+
Regeneration Cd2+ DT Cd2+ Production of Biopolymers
ABCDE Biopolymer Protein yield (mg/3 L) A, Ela38H6 B, Ela58H6 C,
Ela78H6 D, Ela78 E, Ela78H12 Ela38H6 289 Ela58H6 295 Ela78H6 Ela78
Ela78H12 207 191 168 Kostal et al. Marcomolecules, 34, , 2001 MerR
can serve as a specific mercury binding domain
Hg2+ C123 C79 C114 C114 C79 C123 The high binding affinity of
mercury binding by MerR is in accordance with the fact that three
different cysteine residues from the two MerR subunits are involved
in sequestering mercury, which results in a high-affinity
tricoordinate mercury binding site. MerR-Hg complex Selective
Binding of Mercury by Ela153-MerR Biopolymer
Acidic waste water (pH 4) Selectivity of the ELP153MR biopolymer.
Binding of mercury by ELP153MR in the presence of competing heavy
metals. One nmol of biopolymer was mixed with 0.5 nmol of HgCl2 and
various amounts of competing heavy metals. Kostal et al. ES&T
2003 Exploratory Research: Nanotechnology
Acknowledgement R829606 Exploratory Research: Nanotechnology