Carbon Nanotubes as Drug Transportors : A Promising Tool for Cancer Therapy

There is no any any exact method for loading, but by various chemical physical machanisms the drug is loaded on the CNTs.There are various mechanisms by which the drugt molecules can be loaded on the CNTs.
With all atoms exposed on the surface, SWNTs have ultrahigh surface area (theoretically 1300 m2/g) that
permits efficient loading of multiple molecules along the length of the nanotube sidewall. Moreover,
supramolecular binding of aromatic molecules can be easily achieved by π-π stacking of those molecules onto the polyaromatic surface of nanotubes.

The another technology consists of hybridizing drug with functionalized carbon nanotubules (f-CNT), which have the ability to direct and target delivery of peptides or nucleic acids.
Another widely used type of covalent reaction to functionalize CNTs is the cylcoaddition reaction,
which occurs on the aromatic sidewalls, instead of nanotube ends and defects as in the oxidation
case. 2+1 Cycloadditions can be conducted by photochemical reaction of CNTs with azides.
For example Doxorubicin, a commonly used cancer chemotherapy drug, can be loaded on the surface of PEGylated SWNTs with remarkably high loading, up to 4 g of drug per 1 g of nanotube, owing to the ultrahigh surface area of SWNTs.
For any question please reply, I will do my best.

The drug molecules should posses supramolecular binding properties and participate in by π-π stacking onto the polyaromatic surface of nanotubes and by increasing these stackings the drug loding can be incrased.
References:
Liu, Z.; Sun, X.; Nakayama, N.; Dai, H. Supramolecular chemistry on water-soluble carbon nanotubes for drug loading and delivery. ACS Nano 2007, 1, 50 56.
Lee, K. M.; Li, L. C.; Dai, L. M. Asymmetric endfunctionalization of multi-walled carbon nanotubes. J.
Am. Chem. Soc. 2005, 127, 4122 4123.
Moghaddam, M. J.; Taylor, S.; Gao, M.; Huang, S. M.; Dai, L. M.; McCall, M. J. Highly effi cient binding of DNA on the sidewalls and tips of carbon nanotubes using photochemistry. Nano Lett. 2004, 4, 89 93.

http://www.anl.gov/PCS/acsfuel/preprint%20archive/Files/45_4_WASHINGTON%...

http://www.caer.uky.edu/carbon/posters/jagtoyen.pdf.

M. Błachnio, P. Staszczukand G. Grodzicka1
Adsorption and porosity properties of pure and modified carbon nanotube surfaces
Journal of Thermal Analysis and Calorimetry.Volume 94, Number 3 pages 641-648

1 yes, they have the porosity in nano as well as microscale size range.
The multiwalled sampleclearly has a higher mesopore volume with an average pore size of -3.5 nm.

2. There is increase in release /mass transfer/adsortion on increase in porosity

3 procedure for drug loading
There is no any any exact method for loading, but by various chemical physical machanisms the drug is loaded on the CNTs.There are various mechanisms by which the drugt molecules can be loaded on the CNTs.
With all atoms exposed on the surface, SWNTs have ultrahigh surface area (theoretically 1300 m2/g) that
permits efficient loading of multiple molecules along the length of the nanotube sidewall. Moreover,
supramolecular binding of aromatic molecules can be easily achieved by π-π stacking of those molecules onto the polyaromatic surface of nanotubes.

The another technology consists of hybridizing drug with functionalized carbon nanotubules (f-CNT), which have the ability to direct and target delivery of peptides or nucleic acids.
Another widely used type of covalent reaction to functionalize CNTs is the cylcoaddition reaction,
which occurs on the aromatic sidewalls, instead of nanotube ends and defects as in the oxidation
case. 2+1 Cycloadditions can be conducted by photochemical reaction of CNTs with azides.
For example Doxorubicin, a commonly used cancer chemotherapy drug, can be loaded on the surface of PEGylated SWNTs with remarkably high loading, up to 4 g of drug per 1 g of nanotube, owing to the ultrahigh surface area of SWNTs.
For any question please reply, I will do my best.

The drug molecules should posses supramolecular binding properties and participate in by π-π stacking onto the polyaromatic surface of nanotubes and by increasing these stackings the drug loding can be incrased.
References:
Liu, Z.; Sun, X.; Nakayama, N.; Dai, H. Supramolecular chemistry on water-soluble carbon nanotubes for drug loading and delivery. ACS Nano 2007, 1, 50 56.
Lee, K. M.; Li, L. C.; Dai, L. M. Asymmetric endfunctionalization of multi-walled carbon nanotubes. J.
Am. Chem. Soc. 2005, 127, 4122 4123.
Moghaddam, M. J.; Taylor, S.; Gao, M.; Huang, S. M.; Dai, L. M.; McCall, M. J. Highly effi cient binding of DNA on the sidewalls and tips of carbon nanotubes using photochemistry. Nano Lett. 2004, 4, 89 93.

http://www.anl.gov/PCS/acsfuel/preprint%20archive/Files/45_4_WASHINGTON%...

http://www.caer.uky.edu/carbon/posters/jagtoyen.pdf.

M. Błachnio, P. Staszczukand G. Grodzicka1
Adsorption and porosity properties of pure and modified carbon nanotube surfaces
Journal of Thermal Analysis and Calorimetry.Volume 94, Number 3 pages 641-648

yes
the below cited references shows the range of clinical trials performed on CNTs.

References:
1. M. A. Hussain1, M. A. Kabir1 And A. K. Sood. On The Cytotoxicity Of Carbon Nanotubes, Current Science, Vol. 96, No. 5, 10 March 2009.
2. Whitesides, G. M. The “right” size in nanobiotechnology. Nat. Biotech. 2003, 21, 1161 1165.
3. Lowe, C. R. Nanobiotechnology: The fabrication and applications of chemical and biological nanostructures. Curr. Opin. Chem. Biol. 2000, 10, 428 434.
4. Wang, L.; Zhao, W.; Tan, W. Bioconjugated silica nanoparticles: Development and applications. Nano Res.2008, 1, 99 115.
5. Iijima, S. Helical microtubules of graphitic carbon. Nature 1991, 354, 56 58.
6. Dai, H. Carbon nanotubes: Synthesis, integration, andproperties. Acc. Chem. Res. 2002, 35, 1035 1044.
7. Dresselhaus, M.; Dai, H. (eds.) MRS 2004 Carbon Nanotube Special Issue, Vol. 29, 2004.
8. Golberg, D.; Costa, P. M. F. J.; Mitome, M.; Bando, Y. Nanotubes in a gradient electric field as revealed by STM TEM technique. Nano Res. 2008, 1, 166 175.
9. Zhou, W.; Rutherglen, C.; Burke, P. Wafer scale synthesis of dense aligned arrays of single-walled carbon nanotubes. Nano Res. 2008, 1, 158 165.
10. Ago, H.; Petritsch, K.; Shaffer, M. S. P.; Windle, A. H.; Friend, R. H. Composites of carbon nanotubes and conjugated polymers for photovoltaic devices. Adv. Mater. 1999, 11, 1281 1285.
11. Javey, A.; Guo, J.; Wang, Q.; Lundstrom, M.; Dai, H. J. Ballistic carbon nanotube fi eld-effect transistors. Nature 2003, 424, 654 657.
12. Cao, Q.; Rogers, J. A. Random networks and aligned arrays of single-walled carbon nanotubes for electronic device applications. Nano Res. 2008, 1, 259 272.
13. Fan, S. S.; Chapline, M. G.; Franklin, N. R.; Tombler, T. W.; Cassell, A. M.; Dai, H. J. Self-oriented regular arrays of carbon nanotubes and their fi eld emission properties.Science 1999, 283, 512 514.

researches shows that CNTs are transportors.

researches shows that CNTs are transportors.

There is a carbon source which is vaporized by increasing the temperature (1100-1300 C) and a substrate is there which have catalyst & they are maintained at 700 C & the vaporized carbon solidifies on the substrate due to decrease in temperature.

Rererense :
Defense science journal Vol 58 no.5. pp 655-663

please note that the physical and chemical properties are not considered for selecting asubstanse for drug delivery. please refer the other answers of queries for better reasons.
in concern of the Hodgkin's disease there are some papers on peadiatric Hodgkin's disease please refer the NIH website

thanks for your intrest

CNTs are not in Indian market.
till the date they are under research in various DRDO research labs. and Bhaba Atomic Research Centre(BARC).

please refere:

www.drdo.org/
www.barc.ernet.in/ for detail

thanks for your question
regards
toshan kumar sahu

1. substrates: SiO2, Si, Cr-Si etc.
2. catalysts: iron, nitrogen
3. please refer the other query on same presentation
4. size: nanorange
shape: cylindrical

In concern of biological system:

1. Provides enhanced drug delivery through mucous membranes

2. Effectively directs the peptides and nucleic acids to target cells

3. Applicable to a broad range of fields, from respiratory therapy to oncology.

4. In animal experiments, researchers have demonstrated that f-CNT-drug complexes increase absorption of drugs into lung cells versus CNT alone.

5. They are hybridized and the drug can be loaded by ∏-∏ stacking method easily.
6. efficient Drug delivery(reported)
and more ;

The side effects consisting the small scale cytotoxicity. The cytotoxicity at respiratory system is reported.

References:

1. M. A. Hussain1, M. A. Kabir1 And A. K. Sood. On The Cytotoxicity Of Carbon Nanotubes, Current Science, Vol. 96, No. 5, 10 March 2009.

2. Whitesides, G. M. The “right” size in nanobiotechnology. Nat. Biotech. 2003, 21, 1161 1165.

3. Lowe, C. R. Nanobiotechnology: The fabrication and applications of chemical and biological nanostructures. Curr. Opin. Chem. Biol. 2000, 10, 428 434.

4. Wang, L.; Zhao, W.; Tan, W. Bioconjugated silica nanoparticles: Development and applications. Nano Res.2008, 1, 99 115.

5. Iijima, S. Helical microtubules of graphitic carbon. Nature 1991, 354, 56 58.

6. Dai, H. Carbon nanotubes: Synthesis, integration, andproperties. Acc. Chem. Res. 2002, 35, 1035 1044.

7. Dresselhaus, M.; Dai, H. (eds.) MRS 2004 Carbon Nanotube Special Issue, Vol. 29, 2004.

8. Golberg, D.; Costa, P. M. F. J.; Mitome, M.; Bando, Y. Nanotubes in a gradient electric field as revealed by STM TEM technique. Nano Res. 2008, 1, 166 175.

9. Zhou, W.; Rutherglen, C.; Burke, P. Wafer scale synthesis of dense aligned arrays of single-walled carbon nanotubes. Nano Res. 2008, 1, 158 165.

10. Ago, H.; Petritsch, K.; Shaffer, M. S. P.; Windle, A. H.; Friend, R. H. Composites of carbon nanotubes and conjugated polymers for photovoltaic devices. Adv. Mater. 1999, 11, 1281 1285.

11. Javey, A.; Guo, J.; Wang, Q.; Lundstrom, M.; Dai, H. J. Ballistic carbon nanotube fi eld-effect transistors. Nature 2003, 424, 654 657.

12. Cao, Q.; Rogers, J. A. Random networks and aligned arrays of single-walled carbon nanotubes for electronic device applications. Nano Res. 2008, 1, 259 272.

13. Fan, S. S.; Chapline, M. G.; Franklin, N. R.; Tombler, T. W.; Cassell, A. M.; Dai, H. J. Self-oriented regular arrays of carbon nanotubes and their fi eld emission properties.Science 1999, 283, 512 514.

as sush thyere is no any drug properties characterization with respect to CNTs based drug delivery. For delivery applications, the anti-cancer property is first characterized. I found some of the properties after refining the papers.

1. The drug molecules should posses supramolecular binding properties and participate in by π-π stacking onto the polyaromatic surface of nanotubes.
2. they should be photosensitized easily.
3. Should have specifil activity, efficient Melting temperature and density.
4. Enzyme specificity.
5. With higher Stability characters
6. efficient delivery through the mucous membranes

References:

1. M. Grzelczak et al. Angew. Chem. Int. Ed. 2007, 46, 7026-7030
2. M.A. Correa-Duarte and L.M Liz-Marzán J. Mater. Chem. 2006, 16, 22-25
3. M. Sanles-Sobrido et al. Chem. Mater. 2009-ASAP
4. P. Taladriz-Blanco et al. ACS App. Mater. Interface 2009, 1, 56-59.

the below citedreferences shows some clinical work.
References:
1. M. A. Hussain1, M. A. Kabir1 And A. K. Sood. On The Cytotoxicity Of Carbon Nanotubes, Current Science, Vol. 96, No. 5, 10 March 2009.
2. Whitesides, G. M. The “right” size in nanobiotechnology. Nat. Biotech. 2003, 21, 1161 1165.
3. Lowe, C. R. Nanobiotechnology: The fabrication and applications of chemical and biological nanostructures. Curr. Opin. Chem. Biol. 2000, 10, 428 434.
4. Wang, L.; Zhao, W.; Tan, W. Bioconjugated silica nanoparticles: Development and applications. Nano Res.2008, 1, 99 115.
5. Iijima, S. Helical microtubules of graphitic carbon. Nature 1991, 354, 56 58.
6. Dai, H. Carbon nanotubes: Synthesis, integration, andproperties. Acc. Chem. Res. 2002, 35, 1035 1044.
7. Dresselhaus, M.; Dai, H. (eds.) MRS 2004 Carbon Nanotube Special Issue, Vol. 29, 2004.
8. Golberg, D.; Costa, P. M. F. J.; Mitome, M.; Bando, Y. Nanotubes in a gradient electric field as revealed by STM TEM technique. Nano Res. 2008, 1, 166 175.
9. Zhou, W.; Rutherglen, C.; Burke, P. Wafer scale synthesis of dense aligned arrays of single-walled carbon nanotubes. Nano Res. 2008, 1, 158 165.
10. Ago, H.; Petritsch, K.; Shaffer, M. S. P.; Windle, A. H.; Friend, R. H. Composites of carbon nanotubes and conjugated polymers for photovoltaic devices. Adv. Mater. 1999, 11, 1281 1285.
11. Javey, A.; Guo, J.; Wang, Q.; Lundstrom, M.; Dai, H. J. Ballistic carbon nanotube fi eld-effect transistors. Nature 2003, 424, 654 657.
12. Cao, Q.; Rogers, J. A. Random networks and aligned arrays of single-walled carbon nanotubes for electronic device applications. Nano Res. 2008, 1, 259 272.
13. Fan, S. S.; Chapline, M. G.; Franklin, N. R.; Tombler, T. W.; Cassell, A. M.; Dai, H. J. Self-oriented regular arrays of carbon nanotubes and their fi eld emission properties.Science 1999, 283, 512 514.

Thanks for citing the question.

There is no any any exact method for loading, but by various chemical physical machanisms the drug is loaded on the CNTs.There are various mechanisms by which the drugt molecules can be loaded on the CNTs.
With all atoms exposed on the surface, SWNTs have ultrahigh surface area (theoretically 1300 m2/g) that
permits efficient loading of multiple molecules along the length of the nanotube sidewall. Moreover,
supramolecular binding of aromatic molecules can be easily achieved by π-π stacking of those molecules onto the polyaromatic surface of nanotubes.
\

The another technology consists of hybridizing drug with functionalized carbon nanotubules (f-CNT), which have the ability to direct and target delivery of peptides or nucleic acids.

Another widely used type of covalent reaction to functionalize CNTs is the cylcoaddition reaction,
which occurs on the aromatic sidewalls, instead of nanotube ends and defects as in the oxidation
case. 2+1 Cycloadditions can be conducted by photochemical reaction of CNTs with azides.

For example Doxorubicin, a commonly used cancer chemotherapy drug, can be loaded on the surface of PEGylated SWNTs with remarkably high loading, up to 4 g of drug per 1 g of nanotube, owing to the ultrahigh surface area of SWNTs.
For any question please reply, I will do my best.

References:
Liu, Z.; Sun, X.; Nakayama, N.; Dai, H. Supramolecular chemistry on water-soluble carbon nanotubes for drug loading and delivery. ACS Nano 2007, 1, 50 56.

Lee, K. M.; Li, L. C.; Dai, L. M. Asymmetric endfunctionalization of multi-walled carbon nanotubes. J.
Am. Chem. Soc. 2005, 127, 4122 4123.

Moghaddam, M. J.; Taylor, S.; Gao, M.; Huang, S. M.; Dai, L. M.; McCall, M. J. Highly effi cient binding of DNA on the sidewalls and tips of carbon nanotubes using photochemistry. Nano Lett. 2004, 4, 89 93.

Such cylindrical graphitic polymeric structures have novel or improved properties that make them potentially useful in a wide variety of applications in electronics, optics and other fields of materials science. Carbon nanotubes are endowed with exceptionally high material properties, very close to their theoretical limits, such as electrical and thermal conductivity, strength, stiffness, and toughness.
Moreover, MWCNTs are polymers of pure carbon and can be reacted and manipulated using the rich chemistry of carbon. This provides opportunity to modify the structure and to optimise solubility and dispersion, allowing innovative applications in materials, electronics, chemical processing and energy management, to name just a few. In summary, three properties of MWCNTs are specifically interesting for the industry: the electrical conductivity (as conductive as copper), their mechanical strength (Up to 15 to 20 times stronger than steel and 5 times lighter) and their thermal conductivity (same as that of diamond and more than five times that of copper). A combination of these impressive properties enables a whole new variety of useful and beneficial
applications.

Current or short-term applications are often based on the use of MWCNTs as a superior replacement of electrically conductive carbon blacks. Much of the history of plastics over the last half century has been a replacement for metal. For structural applications, plastics have made tremendous headway. However where electrical conductivity is required, metals are still preferred to plastics. This deficiency can be overcome by upgrading plastics with conductive fillers such as carbon black and graphite fibres. However the loading required to provide the necessary conductivity is typically high, and the structural properties of the resulting plastic parts are highly degraded. Due to their high conductivity, high aspect ratio, and natural tendency to form ropes, MWCNTs are ideal in providing inherently long conductive pathways even at ultra-low loadings. The lower loading of additive can offer several advantages such as better processability
or higher retention of the mechanical properties of the original polymer. This is why the use of carbon nanotubes for antistatic and conductive applications in polymers is already a commercial reality, growing in sectors such as electronics and the automotive industry. For these applications, carbon nanotubes can compete with additives such as highly conductive carbon black on a price performance basis. Applications that exploit this behaviour of CNTs include EMI/RFI (electromagnetic and radio frequency interference) shielding composites, electrostatic dissipation (ESD), antistatic materials and (even transparent!) coatings. Concrete examples in the automotive industry are fuel systems components and fuel lines (connectors, pump parts, o-rings, …), exterior body parts for electrostatic painting as well as, in the electronic industry, conveyor belts, manufacturing tools and equipments, wafer carriers,
clean room equipments, etc… Structural composites made of carbon fiber (or glass fiber) and a thermoset (e.g. epoxide) have been improved quite substantially by the introduction of carbon nanotubes. The benefit is not achieved by replacing the reinforcing carbon fiber but by enhancing the properties of the matrix material (epoxide). Almost every sports item on the market can be improved by using CNT. These high-end models are usually used by professional athletes as they are often lighter weighted and more durable. For examples, the tennis champion Roger Federer is playing with CNT reinforced rackets while the famous national Finnish ice hockey team is equipped with CNT reinforced sticks.

Several running applications will be expanded to other industries. For example, the improvement of mechanical properties in epoxy-glassfiber or epoxy–carbon fiber composites already known from the sport industry can also be used in the construction of light weighted composites for wind power generators and in the aircraft industry. Due to the nature of these industries, more technical testing and longer certification time will be required. Other medium term applications may include electrical conductive inks for printable circuits, low cost RFID tags or antennas in cars. In the longer term, Carbon Nanotubes may also play a role in the modification of existing textile materials using electrostatic self-assembly and atomic layer deposition techniques to create novel and customizable surfaces on conventional textile materials with emphasis on natural fibres. This opens the way to the development of smart and intelligent textiles that combine
new innovative functions.

Other application Includes:
Detection of Toxic Organophosphoric Compounds.
Detection of Toxic Proteins and Micro Organisms
Detection Of Alkylating Agents Containing Sulphur And Nitrogen
Detection of chemical and biological warfare agents
As biological and chemical sensors
In designing of CNTs based display device application

References:

Preeti verma Et al carbon nanotubes purification and sorting protocols. DSJ vol-58(5), 2008. 591-599.

Patro et al Nanotechnology applications for chemical and biological sensors. DSJ vol-58(5), 2008. 636-649.

Langer R. Drug delivery and targeting. Nature 1998; 392:5–10.

Moghimi SM, Hunter AC, Murray JC. Long-circulating and target-specific nanoparticles: theory to practice. Pharmacol Rev 2001;53:283–318.

Maeda H, Wu J, Sawa T, Matsumura Y, Hori K. Tumor vascular permeability and the EPRef fect in macromolecular therapeutics: a review. J Cont Rel 2000; 65:271–84.

Gao XH, Cui YY, Levenson RM, Chung LWK, Nie SM. In vivo cancer targeting and imaging with semiconductor quantum dots. Nat Biotechnol 2004;22:969–76.

Bartlett DW, Su H, Hildebrandt IJ, Weber WA, Davis ME. Impact of tumor-specific targeting on the biodistribution and efficacy of siRNA nanoparticles measured
by multimodality in vivo imaging. Proc Natl Acad Sci U S A 2007;104:15549–54.

Iyer AK, Khaled G, Fang J, Maeda H. Exploiting the enhanced permeability and retention effect for tumor targeting. Drug Discov Today 2006;11:812–8.

Feazell RP, Nakayama-Ratchford N, Dai H, Lippard SJ. Soluble single-walled carbon nanotubes as longboat delivery systems for platinum(IV) anticancer drug
design. J Am Chem Soc 2007;129:8438–9.

Liu Z, Sun X, Nakayama N, Dai H. Supramolecular chemistry on water-soluble carbon nanotubes for drug loading and delivery. ACS Nano 2007;1:50–6.

Bianco A, Kostarelos K, Prato M. Applications of carbon nanotubes in drug delivery. Curr Opin Chem Bio 2005;9:674–9.

the mode of action can be described in the following manner:

Activation and Loading of Drug Molecules.
The CNT cellular uptake mechanism may differ depending on the functionalization and size of the CNTs, including endocytosis as reported and several other groups or passive diffusion as observed by the Prato group when CNTs are functionalized (e.g. by 1,3-dipolar cycloaddition). CNTs have been used to efficiently shuttle various biological cargoes, ranging from small drug molecules to biomacromolecules, such as proteins and DNA/RNA, into different types of cells. Once taken up by cells via endocytosis, SWNTs are able to exit cells through exocytosis.

Release of Drug Molecules.
Unlike various small drug molecules which are able to diffuse into cells, biomacromolecules including proteins, DNA, and RNA rarely cross cell membranes by themselves. Intracellular delivery is thus required in order to use these molecules for therapeutic applications. Proteins can be either conjugated or noncovalently absorbed on nanotubes for intracellular delivery [15, 33]. The hydrophobic surface of partially functionalized SWNTs (e.g., oxidized SWNTs) allows non-specific binding of proteins.

For Example: After being translocated into cells by Conjugating paclitaxel (PTX), a widely used cancer chemotherapy drug, to branched polyethylene glycol chains on SWCNTs via a cleavable ester bond to obtain a water-soluble SWNT-PTX conjugate. SWCNTs-PTX affords higher efficacy in suppressing tumor growth than clinical Taxol in a murine 4T1 breast cancer model, owing to prolonged blood circulation and 10-fold higher tumor PTX uptake by SWNT delivery through enhanced permeability and retention. Drug molecules carried into the reticuloendothelial system are released from SWCNTs and excreted via biliary pathway without causing obvious toxic effects to normal organs. Thus, nanotube drug delivery is promising for high treatment efficacy.

References:
Feazell, R. P.; Nakayama-Ratchford, N.; Dai, H.;
Lippard, S. J. Soluble single-walled carbon nanotubes as
longboat delivery systems for platinum anticancer
drug design. J. Am. Chem. Soc. 2007, 129, 8438
8349.

Ali-Boucetta, H.; Al-Jamal, K. T.; McCarthy, D.; Prato,
M.; Bianco, A.; Kostarelos, K. Multiwalled carbon
nanotube-doxorubicin supramolecular complexes for
cancer therapeutics. Chem. Commun. 2008, 459–461.

Murakami, T.; Fan, J.; Yudasaka, M.; Iijima, S.; Shiba, K.
Solubilization of single-wall carbon nanohorns using a
PEG-doxorubicin conjugate. Mol. Pharmaceutics 2006,
3, 407 414.

Sun, X.; Liu, Z.; Welsher, K.; Robinson, J. T.; Goodwin,
A.; Zaric, S.; Dai, H. Nano-graphene oxide for cellular
imaging and drug delivery. Nano Res. 2008, 1, 203
212.

Liu, Z.; Robinson, J. T.; Sun, X. M.; Dai, H. J. PEGylated
nanographene oxide for delivery of water-insoluble
cancer drugs. J. Am. Chem. Soc. 2008, 130, 10876
10877.

Dhar, S.; Liu, Z.; Thomale, J.; Dai, H.; Lippard, S. J.
Targeted single-wall carbon nanotube-mediated Pt(Ⅳ)
prodrug delivery using folate as a homing device. J.
Am. Chem. Soc. 2008, 130, 11467 11476.

Liu, Z.; Li, X.; Tabakman, S. M.; Jiang, K.; Fan, S.; Dai, H.
Multiplexed multi-color Raman imaging of live cells with
isotopically modifi ed single walled carbon nanotubes. J.
Am. Chem. Soc. 2008, 130, 13540 13541.

Chakravarty, P.; Marches, R.; Zimmerman, N. S.;
Swafford, A. D.; Bajaj, P.; Musselman, I. H.; Pantano, P.;
Draper, R. K.; Vitetta, E. S. Thermal ablation of tumor
cells with antibody-functionalized single-walled carbon
nanotubes. Proc. Natl. Acad. Sci. USA 2008, 105,
8697 8702.

McDevitt, M. R.; Chattopadhyay, D.; Kappel, B. J.;
Jaggi, J. S.; Schiffman, S. R.; Antczak, C.; Njardarson,
J. T.; Brentjens, R.; Scheinberg, D. A. Tumor targeting
with antibody-functionalized, radiolabeled carbon
nanotubes. J. Nucl. Med. 2007, 48, 1180 1189.

Kataura, H.; Maniwa, Y.; Kodama, T.; Kikuchi, K.;
Hirahara, K.; Suenaga, K.; Iijima, S.; Suzuki, S.; Achiba,
Y.; Kratschmer, W. High-yield fullerene encapsulation in
single-wall carbon nanotubes. Synth. Met. 2001, 121,
1195 1196.

Jeong, G. H.; Farajian, A. A.; Hatakeyama, R.; Hirata, T.;
Yaguchi, T.; Tohji, K.; Mizuseki, H.; Kawazoe, Y. Cesium
encapsulation in single-walled carbon nanotubes
via plasma ion irradiation: Application to junction
formation and ab initio investigation. Phys. Rev. B 2003,
68, 075410.

Li, L. J.; Khlobystov, A. N.; Wiltshire, J. G.; Briggs, G. A.
D.; Nicholas, R. J. Diameter-selective encapsulation of
metallocenes in single-walled carbon nanotubes. Nat.
Mater. 2005, 4, 481 485.

Kaneko, T.; Okada, T.; Hatakeyama, R. DNA
encapsulation inside carbon nanotubes using micro
electrolyte plasmas. Contrib. Plasma Phys. 2007, 47,
57 63.

Hilder, T. A.; Hill, J. M. Modelling the encapsulation of
the anticancer drug cisplatin into carbon nanotubes.
Nanotechnology 2007, 18, 275704.

I am thankful to you for read and posting the comment on my presentation. Your question is very good to understand the basic mechanism behind the cellular uptake of cancer cells.

There are three key features of this nanoscale drug delivery system (DDS): (a) use of functionalized SWCNTs as a biocompatible platform for the delivery of therapeutic drugs or diagnostics, (b) conjugation of prodrug modules of an anticancer agent (taxoid with a cleavable linker) that is activated to its cytotoxic form inside the tumor cells upon internalization and in situ drug release, and (c) attachment of tumor-recognition modules (biotin and a spacer) to the nanotube surface. To prove the efficacy of this DDS, three fluorescent and fluorogenic molecular probes are designed, synthesized, characterized, and subjected to the analysis of the receptor-mediated endocytosis and drug release inside the cancer cells (L1210FR leukemia cell line) by means of confocal fluorescence microscopy. The specificity and cytotoxicity of the conjugate have also been assessed and compared with L1210 and human noncancerous cell lines. Then, it has been proven that this tumor-targeting DDS works with high potency toward specific cancer cell lines, thereby forming a solid foundation for further development.Chemically functionalized single-walled carbon nanotubes (SWNT) have shown promise in tumor-targeted accumulation in mice and exhibit biocompatibility, excretion, and little toxicity. Here, we show in vivo SWCNTS drug delivery for tumor suppression in mice. Conjugating paclitaxel (PTX), a widely used cancer chemotherapy drug, to branched polyethylene glycol chains on SWCNTs via a cleavable ester bond to obtain a water-soluble SWNT-PTX conjugate. SWCNTs-PTX affords higher efficacy in suppressing tumor growth than clinical Taxol in a murine 4T1 breast cancer model, owing to prolonged blood circulation and 10-fold higher tumor PTX uptake by SWNT delivery through enhanced permeability and retention. Drug molecules carried into the reticuloendothelial system are released from SWCNTs and excreted via biliary pathway without causing obvious toxic effects to normal organs. Thus, nanotube drug delivery is promising for high treatment efficacy

References:

1. Service, R. F., Calls rise for more research on toxicology of nanomaterials. Science, 2005, 310, 1609.
2. Hurt, R. H., Monthioux, M. and Kane, A., Toxicology of carbon
nanomaterials: Status, trends, and perspectives on the special
issue. Carbon, 2006, 44, 1028–1033.
3. Murakami, T., Ajima, K., Miyawaki, J., Yudasaka, M., Iijima, S. and
Shiba, K., Drug-loaded carbon nanohorns: adsorption and release of
dexamethasone in vitro. Mol. Pharm., 2004, 1, 399–405.

I hope the answer is satisfactory, but if you have any questions on this please reply and give me the chance to serve to my best.

with regards
roshan kumar sahu

thank you for posting the comment on my presentation

i am coming directly on answer. CNTs can also be considered very promising vectors for gene-encoding nucleic acids. Stable complexes between cationic CNTs and plasmid DNA and demonstrated the enhancement of the gene therapeutic capacity in comparison to DNA alone. On the other hand, CNTs conjugated antigenic peptides can be developed as a new and effective system for synthetic vaccine applications. What makes CNTs quite unique is their ability, to passively cross membranes of many different types of cells following a translocation mechanism that has been termed the nanoneedle mechanism. In that way, CNTs have open innumerable possibilities for future drug discovery based on intracellular targets. Moreover, adequately functionalized CNTs can be rapidly eliminated from the body following systemic administration offering further encouragement for their development. CNTs excretion rates and accumulation in organs and any reactivity with the immune system, determine the CNTs safety profile and, consequently, any further pharmaceutical development. Caution is advised about the need for systematic data on the long-term nano-objects in correlation with the type of CNT material used. CNTs are gradually playing a bigger and more important role in the emerging field of nanomedicine[1].

However, concerns about the potential toxicity, with a potential, of single-walled Carbon Nanotubes have been raised. Examinations on the acute and chronic toxicity of functionalized single-walled Carbon Nanotubes when injected into the bloodstream of mice were performed and clinical and laboratory parameters reveal no evidence of toxicity over 4 months. Histology and Raman microscopic mapping demonstrate that functionalized Single-Walled Carbon Nanotubes persisted within liver and spleen macrophages for 4 months without apparent toxicity[2].

(1)Prato M, Kostarelos K, Bianco A. Functionalized carbon nanotubes in drug design and discovery. Acc
Chem Res. 2008 Jan; 41(1):60-8.

(2)Schipper ML, Nakayama-Ratchford N, Davis CR, Kam NW, Chu P, Liu Z, Sun X, Dai H, Gambhir SS. A
Pilot Toxicology Study of Single-Walled Carbon Nanotubes In A Small Sample Of Mice. Nat Nanotechnol.
2008 Apr;3(4):216-21.

but if you have any questions on this please reply and give me the chance to serve to my best.

with regards
roshan kumar sahu