Barriers in implementing nano drugs

Barriers in implementing nano drugs
Nanotechnology involves the engineering of functional atoms at the molecular scale. Such systems are characterised by unique physical, optical and electronic features that are attractive for disciplines ranging from materials science to biomedicine. The National Nanotechnology Initiative defines the nanoscale materials as particles ranging approximately between 1-100 nm size regime in at least one dimension. One of the most active research areas of nanotechnology is nano drugs, which applies nanotechnology to highly specific medical interventions for the mitigation, prevention, diagnosis and treatment of diseases. Some commonly used nano drug delivery systems are liposomes, nanoemulsions, solid-lipid nanoparticles, nanocapsules, polymer-based nanoparticles, micelles, nanogels, dendrimers, inorganic nanoparticles, quantum dots, iron oxides, ceramic nanoparticles and silver nanoparticles.

There are several challenges faced by the patients on the use of conventional large size drug materials and some of them are:
  • Poor bioavailability due to poor solubility
  • In vivo stability
  • Poor intestinal absorption due to poor solubility
  • Sustained and targeted delivery to the site of action
  • Poor therapeutic effectiveness due to subtherapeutic level
  • Generalised side effects and toxicity due to excessive dose or dose dumping of conventional sustained/controlled formulations
  • Plasma fluctuations of drugs

  • Although progress in the application of nanotechnology to drug delivery has been dramatic and successful, as evidenced by some nano drugs now in the market, several main challenges remain in this field. In order for nano drugs to progress towards human applications, a better understanding of the mechanisms underlying intracellular uptake, trafficking and the fate of nanomaterials in complex biological networks is needed.

    Nano drugs may contribute to the formation of free radicals, damage of brain cells and undesirable penetration through the epidermis or other physiological barriers into the areas of the body that are more susceptible to toxic effects. Several mechanisms have been proposed to affect the toxicity of nano drugs depending on different factors derived from the physiochemical properties, physical characteristics and environmental conditions. For example, naked quantum dots show cytotoxicity by induction of reactive oxygen species, resulting in the damage of the nucleus, mitochondria and plasma membranes. Some other toxicities of nano drugs are reactive oxygen species generation resulting oxidation of cellular constituents, such as mitochondria dysfunction, lipid peroxidation, changes in cell morphology, etc. Some cationic nanoparticles can cause haemolysis and blood clotting while neutral and anionic nanoparticles are quite nontoxic. Nanoparticles can be inhaled, ingested or absorbed through the skin and they can penetrate the cells, even into the cells’ nucleus and can induce some change in the genetic material.

    Another barrier facing nano drug delivery is the large-scale production in terms of scaling pilot technologies for consistent and reproducible production and commercialisation. This may be due to the nature of the preparation technique and high cost of materials employed. The challenges of scaling up include a low concentration of nanomaterials, agglomeration and the chemistry process. Nano products are likely to encounter great hurdles because of their costs and complexity. Despite the number of patents for nano drug delivery technologies, commercialisation is still in its early stage. Because of the high development costs of nano drugs and medical devices, small companies have trouble in bringing the products to the market.

    In summary, based on the integration of disciplines, nanotechnology is an industrial revolution, which may change every aspect of human life.
    How to cite this article:
    Mohd Yasir. Barriers in implementing nano drugs. BioLim O-Media. 17 February, 2016. 4(2).
    Available from: http://archive.biolim.org/omedia/read/BOMA0109.