nanodevices, nanomedicine, nanotechnology
R Kumar. The Emerging Therapy of Tomorrow with Nanomedicine: Present Status. The Internet Journal of Neurology. 2007 Volume 10 Number 1.
Nanomedicine is new concept in combining nanotechnology and medicine. Nanotherapeutics is the use of nanomedicine in therapy. The definition of nanomedicine require attention as the nanotechnology represents a cluster of technologies. This article outlines present development in nanomedicine and prospect in nanotherapeutics. Health and safety issues also are discussed.
Richard Feynman a nobel Laurete predicted the emergence of a new science called nanotechnology in 1959, as this deals with structure of one to one hundred nanometers in scale 1 . Nanotechnology is term used to define the products, processes and properties at the nano/micro scale that have resulted from the convergence of the physical, chemical and life sciences. National Nanotechnology Initiative (NNI) defines nanotechnology as research and development at the atomic, molecular or macromolecular levels in the sub-100nm range (0.1-100nm) create structure, devices, and system that have novel functional properties 2,3 . Definition of nanotechnology as proposed by Bawa and Colleagues 4 . 'The design; characterization, production and application of structures, devices and systems by controlled manipulation of size and shape at the nanometer scale (atomic, molecular and macromolecular scale) that produces structures, devices and systems with at least one novel / superior characteristic or property. Nanotechnology is not new technology for eg. protein vaccines some peptiders and viruses also molecular medicine and biotechnology may be considered nanotechnology 2,3 . Nanotechnology will have a profound impact on the future of medical practice.
Nanomedicine is a combination of nanotechnology and medicine and it provide new direction in medical diagnosis, monitering and treatment at the level of single molecules or molecular assemblies at the “nano” scale of about 100nm or less. Nanomedicine defined as “the monitoring, repair, construction, and control of human biological systems at the molecular level, using engineered nanodevices and nanostructures 5 . Nanomedicine is the application of nanoscale technologies to the practice of medicine. It is used for diagnosis, prevention and treatment of disease and to gain increased understanding of underlying disease mechanisms. Presently nanomedicine involves detection of particles, drug delivery system, emulsions, and carriers for delivering vaccines: and biomaterials with unusual properties and improved biocompatibility. Nanotechnology is also biomimicry i.e. to understand the natures solution towards biological system or to learn from nature 6 .
Nanomedicine technologies and techniques: in process of patent ,,,,,,
In the following areas of nanomedicine including drug delivery 14,15 :
Synthesis and use of novel nanomaterials and nanostructures.
Biomimetic nanostructures (synthetic products developed from and understanding of biologic systems).
Devices and nanosensors for detection of diseases and pathogens (eg, polymerase chain reaction-coupled micro/nano-fluidic devices).
Identification of novel biologic targets / receptors / ligands for imaging diagnosis, and therapy (eg, for cancers and for neurodegenerative and cardiovascular diseases).
Theranostics – Construction of multifunctional biologic nanostructures, devices, and systems for diagnosis and combined drug delivery.
Nanotechnology for tissue engineering, and regenerative medicine.
Stimuli-sensitive nanodevices and physically targeted treatments.
Miniaturized nanofluidic devices and systems that transport fluids more efficiently to the site of delivery.
More efficient site-specific targeting by way of nanodrugs, resulting in with reduces systemic side effects and better patient compliance.
Close-looped drug delivery nanodevices and implants containing sensors on the same chips.
Microsurgical devices, molecular motors, or nanobots that are capable of navigating throughout the body to repair damaged sites, destroy tumors or viruses, and even perform gene therapy.
Nanodevices and categories of nanomedicine
Nanoparticles and nanodevices eg. Nanobiosensors and nanobiochips are being used to improve drug discovery and development. Drug targeting by using nanoparticle should reduce systemic toxicity, encapsulation and nanocarriers protect drugs from metabolism and from excretion. Drug diffusion through pore (in organic aluminium oxide nanoporous filter) – a novel method of administering antiangiogenic and antioxidant drugs. In the treatment of proliferative vascular disease.
The role of nanomedicine in dermatology, to provide, state of art patient care. Gold nanoparticle, quantam dot and magnetic nanoparticles are used in nanoimaging. In noninvasing imaging of skin high resolution dermoscopy, microscopy and spectroscopy offer advance diagnostic and therapeutic modalities.
To increase the efficacy of anticancer drug and to reduce the toxic effect, a polymeric misceller and liposome based delivery system conjugated to tumor specific ligands have been studied 51,52,53 . In prostatic tumor – the tumor cell overexpress transferring receptor and for targeting drug to tumor, ligand transferring has been investigated 54 . For the treatment of a localize prostatic tumor the approach is direct intertumoral delivery of biodegradable nanoparticles, a controlled release formulation, providing sustained drug effect 55 . The drugs intracellular adhesion molecular (ICAM-1) protect endothelial cell from oxidative damage by reactive oxygen species particle. ICAM-1 is a good target for vascular immunotargeting of nanoparticle to the damage endothelium 56 . Carbon nanostructure - Fullerenes could be potential drugs in future. In the treatment of neurodegeneratic disorder like parkinsonism, multiple sclerosis and other disease that are associated with oxidative stress and damage. Fullerens can be use an alternative to chelating agent. Fullerenes also known as bulky ball (cluster of carbon C 60) 57 . Fullerenes are resistant to biochemical degradation within the body – produce less adverse effect, nanotechnology faciliate the drug delivery. “Pharmacies on a chip” 58 researcher at the Massachusetts institute of technology achieved a controlled release of drug from microchip. Poly (Liactic acid) microchip device were manufactured to contain 36 drug reservoir 59 .
An immunosuppresant agent sirolimus was approved by FDA as a solid dose formulation in year 2000 60 .
Studies in human showed that deposition of nanoparticle in the lungs increases with decreasing particle size and the toxicity of inhaled insoluble nanomaterials increases with decreases particle size and increasing particle surface area 61 . Certain classes of nanoparticle could be responsible for destructive inflammatory processes in the lungs eg. carbon black nanoparticle may induce a type-II alveolar epithelial cell line to release pro-inflammatory mediators.
Nanotechnology changes the properties of substance eg. Carbon as fullerens and nanotubes an attractive candidate for applications but also make them dangerous, when expose to environment. The measures for safety needs to be taken on environmental concern with the use of nanotechnology 62 . Nanomedicine have potential to cross blood brain barrier 63 may cause harm to the patient.
The verichip corporation has declared the availability of the world first and only patented, FDA – cleared radiofrequency identification implantable microchip 64 , with this ethical question arises about patient own personal detail which is available to other 64 . Privacy and confidentiality of the patients may be affected. Goldstcin 65 state that by eg. 2016 “-------- your doctor will be capable of scanning your entire genome within a few minutes”. The protection and maintenance of health information of the patient is the ethical issue, and while using nanotechnology in medical field ensuring privacy and confidentiality is of utmost importance.
A clear definition of nanotechnology is an issue that require attention. Nanotechnology represents a cluster of technologies with different characteristic and applications. Nanomedicine related applications are under development and this is a long process of converting nanomedicine in to commercially viable products. The ultimate goal of nanotherapeutic is comprehensive monitoring repair and improvement of all human biologic system. There is great concern over the environmental and health risk with the use of nanomedicine. The protection and maintenance of health information of the patients is the ethical issue and ensuring privacy & confidentiality is of utmost importance while using nanomedicine.
Address for Correspondence
Dr. Rajiv Kumar, MD # 1156-B, Sector 32-B, Chandigarh, INDIA. e-mail: DRrajiv.email@example.com