Multi-Functionalised Nano-Graphene Oxide Nanocarriers in Controlled Release & Drug Delivery

2-D graphene provides outstanding properties that are currently being studied. These outstanding properties include:

• Electronic properties; 
• Thermal properties; 
• Mechanical properties. 

For example, 2-D graphene is currently being explored in the following applications (among many other applications):

• Advanced nanoelectronics; 
• Nanomembranes; 
• Nanocomposites. 

In this article, I will discuss some of the applications of nano-graphene oxide in nanomedicine.

Nano-graphene oxide (NGO) is a single-layer of graphene oxide sheets with a lateral width of a few nanometres.

The Journal of Materials Chemistry published on 19 Nov 2010 a work titled "Multi-functionalized graphene oxide based anticancer drug-carrier with dual-targeting function and pH-sensitivity". Scientists from P. R. China designed a nano-graphene oxide (NGO) anticancer drug nanocarrier that combines different targeting mechanisms.

Many anti-cancer drugs are toxic and/or cause undesirable side-effects. This is due to the fact that these anti-cancer drugs:

• Target tumour cells; 
• And also target healthy cells. 

A team of scientists leaded by Yongsheng Chen (from Nankai University, P. R. China) have developed a controlled release system using multi-functionalised NGO as a drug nanocarrier for drug delivery.

The team headed by Chen selected NGO to build up the drug nanocarrier because this nanomaterial has a very high surface area available. Thus, NGO presents high ability to carry a large amount of drug, thereby contributing to a more efficient therapy and with increased yield, on the standpoint of dosage.

The NGO was multi-functionalized in order to become targeted. For this purpose, the Chen's team used several approaches:

• The team headed by Chen linked super-paramagnetic Fe3O4 nanoparticles to the NGO nanocarrier. By proceeding this way, the NGO nanocarrier became targeted to the tumour cells by an external magnetic field;
• Many cancer cells have a high number of folate receptors on their external cellular surface. As a consequence of this fact, folic acid is a targeting agent of some (not all) tumour cells. Therefore, the Chen's team attached folic acid to the nanoparticles. More precisely, the Chen's team conjugated folic acid onto Fe3O4 nanoparticles via the chemical linkage with amino groups of the 3-aminopropyl triethoxysilane (APS) modified superparamagnetic NGO–Fe3O4 nanohybrid, in order to generate the multi-functionalized NGO. This procedure made the NGO nanocarrier more likely that the drug nanocarrier will enter cancer cells rather than healthy cells;
• Cancer cells are typically more acidic than healthy cells. Therefore, the Chen's team developed the NGO nanocarrier with the ability to increase drug release when the pH value of the surrounding environment decreases. This mechanism warrants that the drug is released to the tumour cells, minimizing this way the uptake of anti-cancer drug by healthy cells.

After multi-functionalization process, the NGO nanocarriers were then loaded (via π–π stacking or pi-pi stacking) onto the surface of this multi-functionalized NGO with a strong anti-cancer drug: Doxorubicin Hydrochloride (Dox).

Cell uptake studies were carried out the Chen's team, using fluorescein isothiocyanate labelled or Dox loaded multi-functionalized NGO drug nanocarrier to evaluate:

• Their targeted delivery property; 
• Toxicity to tumour cells. 

These studies focused on cell uptake and toxicity were carried out in human breast cancer cells in vitro. The results show that this multi-functionalized NGO drug nanocarrier has potential applications for targeted delivery and the controlled release of anticancer drugs.

Obviously this scientific breakthrough needs further studies aiming improvement in what concerns toxicology, biodegradability and passing from the in vitro studies to humans. Anyway, this discovery has intrinsic value and may pave the way for progress in nanotechnology in drug delivery.

This scientific breakthrough is relevant due to the following reasons:

• Progress was achieved in the improvement of targeting of nanocarriers against cancer cells; 
• The effectiveness of treatments is improved, since practically all the anti-cancer drug is delivered to cancer cells; 
• The undesirable side-effects for patients are significantly reduced; 
• Progress was achieved in the applications of graphene (in this case, graphene oxide) in controlled release and nanotechnology in drug delivery. 

For further information, I suggest to readers the following links (which served as the basis for this article):

http://www.rsc.org/Publishing/ChemScience/Volume/2010/12/targeting_tumours.asp

http://pubs.rsc.org/en/Content/ArticleLanding/2011/JM/c0jm02494e

Good Winds From FDA

The U.S. Food and Drug Administration (FDA) published yesterday (April 9, 2012) in YouTube a video entitled "Innovation Pathway at FDA."

Personally I really like the video and especially the positive message it conveys. Here in my blog I give my Sincere Congratulations to the FDA by the video, and especially by the highly positive message it sends.

This message is a very strong set of clear positive signs of optimism, hope, constructive spirit, innovative spirit, proactive and highly dynamic attitude announced to the world.

As far as I know, FDA is among their counterparts around the world an entity with an unquestionable credibility and effectiveness. My perception is that FDA is the reference with respect to regulations in the areas it is responsible.

However, FDA has been discussed in the most recent years with destructive attacks and comments. For example:

• Apparently innocent criticism;
• Explicit accusations of not updating (or updating very slowly) its regulations when confronted with new challenges brought by an emerging new reality which includes the requirement for innovation and new and emerging sciences and technologies;
• Unfounded conspiracy theories which proliferate throughout the Internet;
• Sensationalist news trying to undermine the credibility of this organization.

Some of these attacks had eventually caused some abrasion on the image of FDA as an organization.

Therefore, FDA needed to launch a campaign containing a very strong message of positivism, optimism, hope and confidence addressed to the world.

The reality has changed in recent years. It is a fact that reality has changed and will change constantly. Thus, FDA and similar organizations must adapt to new realities, new paradigms and the requirements they entail.

But what really happened in the most recent years that really made ​​this change and therefore lead to attacks on FDA and similar organizations, and consequently the release of this video?

Several changes took place.

Firstly, the counterfeit medicinal products began to proliferate in practically the entire world. The counterfeit drugs have become a real scourge in terms of public health and a threat to the pharmaceutical industry.

Moreover, nanoscience and nanotechnology grew and developed at an impressive speed.

Similarly, nanomedicine grew and developed at a considerable speed. Nanomedicine gained critical mass and is proving to have potential to contribute constructively to improve medicine and biomedicine. This is just the beginning. Many more discoveries are to be announced and to a higher speed.

Likewise also grown and developed the applications of nanotechnology-based products in the food & beverages sector. This includes not only food, but also packaging and manufacturing processes.

With the fast development of nanotechnology with applications in medicine (nanomedicine) and in the food & beverages industry, have also emerged real risks associated with toxicity, both environmentally and in terms of public health. These risks are directly related to nanoengineered nanoparticles (nanoparticles intentionally modified by humans for the fulfilment of certain specific purposes). Scientific studies show that these nanoparticles (in opposition to naturally occurring nanoparticles) present the greatest risks to the environment and public health, with respect to toxicity.

Anyway, regulating with quality and adjusted to the real needs of today's society (especially regarding nanotechnology-based health products and food & beverages) is an enormous task, having a complexity of unique proportions. I would say, of historic proportions. It is a complicated challenge and only give good results if integrated, coordinated, standardized and implemented with much committed collaboration with different players, such as innovators, scientists, R&D institutions, universities, industries, health professionals, consultants, IT professionals and many more players.

It is notorious that the video puts much emphasis on technological innovation and collaboration. It is an extremely strong reinforcing of confidence message. In my opinion this message is fully justified, to calm down conspiracy theories and media sensationalism.

This version was published on April 11, 2012, since the original one was removed.

In these areas of science and technology, the worst that can happen is a lack of regulation, which causes a gray zone, providing opportunities to bad professional journalists to make pieces of questionable quality, thus generating fears, suspicions and unfounded conspiracy theories.

FDA is really working hard. I did not learn that with this video. I had already noticed with various press releases issued recently, mainly during the year of 2011 and during the current year. This video just confirmed what I already knew.

However, the ordinary citizen, who is not involved in these matters, did not know. Through this video, the ordinary citizen gets to know.

The tasks that FDA faces are of odd proportions and dimensions absolutely gigantic in the history of our civilization. I can only wish the greatest success to FDA and give them strength.