04-05-2012, 11:52 AM
NANOTECHNOLOGY AND CANCER BIOLOGY
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INTRODUCTION:
Nanotechnology has made big strides in the last 17 years across the world and it will never cease to exist as its applications are enormous.It is no doubt to say that nanotechnology is the future.its development and applications involves all areas of sciences like physics,chemistry,biology and mathematics and all streams of engineering.
It deals with structures of the size 100 nanometers or smaller in atleast one dimenson and involves developing of materials or devices within that size.the small size of nanoparticles (10 to 100 nanometers), allows them to preferentially accumulate at tumor sites because tumors lack an effective lymphatic drainage system. it is possible to manufacture multifunctional nanoparticles that would detect, image, and then proceed to treat a tumor This question is under vigorous investigation; the answer to which could shape the future of cancer treatment. A promising new cancer treatment that may one day replace radiation and chemotherapy is edging closer to human trials. Kanzius RF therapy attaches microscopic nanoparticles to cancer cells and then "cooks" tumors inside the body radio waves that heat only the nanoparticles and the adjacent cancerouscells.
NANO SHELL:
A nanoshell is a type of spherical nanoparticle consisting of a dielectric core which is covered by a thin metallic shell (usually gold). These nanoshells involve a quasiparticle called plasmon which is a collective excitation or quantum plasma oscillation where the electrons simultaneously oscillate with respect to all the ions.
The simultaneous oscillation can be called plasmon hybridization where the tunability of the oscillation is associated with mixture of the inner and outer shell where they hybridize to give a lower energy or higher energy. This lower energy couples strongly to incident light whereas, the higher energy is an anti-bonding and weakly combines to incident light. The hybridization interaction is stronger for thinner shell layers, hence, the thickness of the shell and overall particle radius determines which wavelength of light it couples with. Nanoshells can be varied across a broad range of the light spectrum that spans the visible and near infrared regions. The interaction of light and nanoparticles affects the placements of charges which affects the coupling strength. Incident light polarized parallel to the substrate gives a s-polarization , hence the charges are further from the substrate surface which gives a stronger interaction between the shell and core. Otherwise, a p-polarization is formed which gives a more strongly shifted plasmon energy causing a weaker interaction and coupling.
ONCOLOGY IS CONCERNED WITH:
* The diagnosis of any cancer in a person
* Therapy (e.g., surgery, chemotherapy, radiotherapy and other modalities)
* Follow-up of cancer patients after successful treatment
* Palliative care of patients with terminal malignancies
* Ethical questions surrounding cancer care
* Screening efforts:
* of populations, or
* of the relatives of patients (in types of cancer that are thought to have a hereditary basis, such as breast cancer)
DIFFERENCE BETWEEN CANCER AND TUMOUR:
A tumor or tumour is the name for a swelling or lesion formed by an abnormal growth of cells (termed neoplastic). Tumor is not synonymous with cancer. A tumor can be benign, pre-malignant or malignant, where as cancer is by definition malignant.
A benign tumor is a tumor that lacks all three of the malignant properties of a cancer. Thus, by definition, a benign tumor does not grow in an unlimited, aggressive manner, does not invade surrounding tissues, and does not metastasize. Common examples of benign tumors include moles and uterine fibroids.
The term "benign" implies a mild and nonprogressive disease, and indeed, many kinds of benign tumors are harmless to the health. However, some neoplasms which are defined as 'benign tumors' because they lack the invasive properties of a cancer, may still produce negative health effects. Examples of this include tumors which produce a "mass effect" (compression of vital organs such as blood vessels), or "functional" tumors of endocrine tissues, which may overproduce certain hormones (examples include thyroid adenomas, adrenocortical adenomas, and pituitary adenomas).
Benign tumors typically are encapsulated, which inhibits their ability to behave in a malignant manner. Nonetheless, many types of benign tumors have the potential to become malignant and some types, such as teratoma, are notorious for this.