Nanotechnology in the Delivery of Chemicals to a Specific Location February 19, 2010 S3: James...
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Transcript of Nanotechnology in the Delivery of Chemicals to a Specific Location February 19, 2010 S3: James...
Nanotechnology in the Delivery of Chemicals to a
Specific Location
February 19, 2010
S3: James Kancewick, Michael Koetting, Bradford Lamb
http://www.pharmainfo.net/files/u2882/nanoparticles_0.jpg
Overview
• Medical field – Highly selective approach– Nano– Personalized medicine– Implantable delivery
systems– Easy and Cheap
“Reversibly Stabilized Multifunctional Dextran Nanoparticles Efficiently Deliver Doxorubicin into the Nuclei of Cancer Cells”
By: Ming, Zhong, et al.
http://www.topnews.in/health/files/cancer-cells1.jpg
Traditional Treatment—Chemotherapy
• Cancer caused by genetic mutations that lead to uninhibited growth
• Chemotherapy treats this by either:– Triggering apoptosis (programmed cell death)– Inhibiting cell division
http://cdin.us/01pics/electron-pics/breast-cancer-cells.jpg
Traditional Treatment—Chemotherapy
• Targets most rapidly dividing cells (usually cancer cells)
• Side effect: other rapidly dividing cells are also affected– Hair– Nails– Intestinal lining
http://www.beasurvivor.com/images/ch12im12.jpg
Nanovehicular Intracellular Targeting
• Uses nanotechnology to deliver anti-cancer drugs to cancerous cells only
• Nanovehicles increase drug specificity by directing drugs to specific locations in the cell (e.g. nucleus) before releasing drug molecule
Nanovehicles for drug delivery in 2006 study from Netherlands
http://www.medgadget.com/archives/img/765467intel.jpg
• Most nanovehicles that have been studied are polymer nanoparticles that deliver the toxins doxorubicin (DOX) or paclitaxel (PTX)
• Benefits– Enhanced aqueous solubility– Preferential accumulation at tumor
sites– Reduced side effects– Increased circulation time
• Issues– Low stability– Premature release of drug compound– Few of the studied compounds are
biodegradable, and therefore not well-suited to medical use
http://www.eurekalert.org/multimedia/pub/web/4370_web.jpg
Nanovehicular Intracellular Targeting
Dextran Nanoparticles• Ming, Zhong, et al. developed
dextran nanoparticles by crosslinking dextran and lipoic acid derivatives (Dex-LAs) with catalytic dithiothreitol (DTT)– Highly water soluble– Stable in both dilute and high
salt areas– Biocompatible– Diverse (based on specific
structure)– High drug loading efficiency
(84%)http://www3.interscience.wiley.com/journal/
123189887/abstract
Dextran Nanoparticles• Mechanism
– Nanoparticle self-assembles in water from Dex-LAs
– Binds DOX while in non-reductive environment outside of cells
– Particle/DOX enter cell– Reductive properties of
glutathione (GSH) tripeptides release DOX into nucleus
– GSH is more concentrated in cancerous cells
– Nanoparticles remain in cell and are broken down to safe products dextran and lipoic acid
http://www3.interscience.wiley.com/journal/123189887/abstract
Dextran Nanoparticles
• Nanoparticle cross-linking reduces size of nanoparticles by 10-25%– Easier transport into
cells• Cross-linking was
also found to increase selectivity without adversely affecting drug delivery rate http://www3.interscience.wiley.com/journal/
123189887/abstract
Further Research
• Current nanotechnology based therapy research aids traditional methods– Should find ways to
use nanotechnology to enable better treatment mechanisms
– New drugs that are less destructive and more selective
http://www.fhcrc.org/science/pacr/_private/image_files/student_lab2.jpg
Carbon Nanotubes Are Able ToPenetrate Plant Seed Coat andDramatically Affect Seed Germinationand Plant GrowthMariya Khodakovskaya,†,* Enkeleda Dervishi,†,‡ Meena Mahmood,†,‡ Yang Xu,†,‡ Zhongrui Li,†,‡Fumiya Watanabe,‡ and Alexandru S. Biris†,‡,* Obtained from Nature Online
http://pubs.acs.org/doi/full/10.1021/nn900887m
Control Tomato Seed
No carbon Nanotubes
Seed placed in medium
with carbon nanotubes
Results For Tomato seeds
• Significant shorting of germination time• Increased Germination percentage
rates
• Seedlings with developed cotyledons and root system were recognized as fully germinated in this experiment
12 days 20 days
Regular 32% 71%
Treated 74-82% 90%
Results for Tomato Seeds
• Fresh weight of total biomass (leaves, stems and roots) increased 2.5 fold for carbon nanotube treated seeds.
http://www.landrethseeds.com/photos/Tomato/Tomato%20Pictures/German%20Giant.jpg
Could this work for other plants?
• Yes, and no further research is needed.
http://www.flowerpictures.net/adenium/
images/clark_seeds_3months.jpg
http://4.bp.blogspot.com/_UzKDjjtny_o/Sqqn0Em_iDI/AAAAAAAAA2s/8LhE2IqcAzM/s200/Carbon+Nanotubes+Could+Make+Efficient+Solar+C
ells.jpg
Other Areas Of Agriculture Nanotechnology Applications
• Precision Farming– Sensors
• Smart delivery systems– pesticides and
herbicides
http://www.treehugger.com/20100112-corn-field.jpg
Sources• Li, Yu-Ling, Li Zhu, Zhaozhong Liu, Ru Cheng, Fenghua Meng,
Jing-Hao Cui, Shun-Jun Ji, and Zhiyuan Zhong. "Reversibly Stabilized Multifunctional Dextran Nanoparticles Efficiently Deliver Doxorubicin into the Nuclei of Cancer Cells." Angewandte Chemie International Edition 48.52 (2009): 9914-918. Wiley Interscience. Wiley, 24 Nov. 2009. Web. 12 Feb. 2010. <http://www3.interscience.wiley.com/journal/123189887/abstract>.
• Khodakovskaya, Mariya, Enkeleda Dervishi, Meena Mahmoud, Yang Xu, Zhongrui Li, Fumiya Watanabe, and Alexandru S. Biris. "Carbon Nanotubes Are Able To Penetrate Plant Seed Coat and Dramatically Affect Seed Germination and Plant Growth." ACS Nano 3.10 (2009): 3221-227. ACS Publications. ACS, 22 Nov. 2009. Web. 12 Feb. 2010. <http://pubs.acs.org/doi/abs/10.1021/nn900887m>.
Group S3 Rebuttal
• On the whole, comments were generally very positive.
• Most negative comments centered on the presentation having too much info on some slides. The topics discussed were very information dense and thus mandated a lot of details be presented; however, we agree that some slides could have been split up into two slides for easier viewing.
Notes on Presentation
Positive Notes• James was very enthusiastic
and interested in topic• Good use of model• The slide on chemotherapy
was very educational• Michael was very
knowledgeable on background chemistry
Opportunities for Improvement
• Need more background information– Introduction was too short
• Too much text on some slides– Information was good– Needs to be spread out
Group S1
The Good
• Really liked the use of the fruit to demonstrate the principles
• Lots of pictures that helped explain the topic• Presenters appeared enthusiastic and
knowledgeable
The Not-So-Good
• No mention of further research areas• Failed to address toxicity• Could mention that the paper didn’t talk
about the fruit produced, only the plant during gemination
Scott MarwilDanielle MillerJoshua Moreno
Group S4Review of Nanotechnology Use
in Delivery of Chemicals
Things Done Well
Very good job with the illustrations and the animations especially the model about the nanotubes that was presented
The group did a good job of answering the classes questions in a full and in-depth manner
The group members presenting knew the material and did an good job relaying that knowledge onto the rest of the class
Things That Need Improvement
The overall presentation was actually very good and not a lot of improvements are needed
One thing I do think needs changing is that the conclusion wasn’t that good. The introduction was fantastic but the conclusion left the listener hanging. The questions did help wrap things up though and the group presenting did a good job answering questions.
Group S5Review of Nanotechnology Use in
Delivery of Chemicals
Pradip RijalJason SavatskyTrevor SeidelLaura Young
Presentation Review
• The groups power presentation and visuals were very well done.
• The oral presentation was solid and it was very easy to understand them.
• The group clearly learned from other groups mistakes and was able to not make the same mistakes.
• Some of the slides were a little wordy and detracted from the oral presentation.
Critique by Group S6
Michael Trevathan, Daniel Arnold, John Baumhardt, and Michael Tran
Presented by S3
Group S6Review of Nanotechnology Use
in Delivery of Chemicals
Summary
It was creative to use straws and fruits to demonstrate how carbon nano-tubes are used in the agricultural industry
It was excellent to discuss more than one application for a single technology: medicinal applications and agricultural applications.
The use of pictures and graphs were very well done and they were a great supplement to the text.
The negative impact on humans resulting from the use of nanoparticles in agriculture should have been discussed.