Biomedical Engineering Reference
In-Depth Information
used quantum dots that were attached to epithelial growth factor receptor
and were conjugated with anti-growth antibody, to detect early biomarkers
of cervical cancer. Cross et al. [84] installed a tiny probe on a spring using
nanotechnology, and used it to explore a cell surface and measure its soft-
ness, which was used as a marker to determine whether carcinogenesis had
occurred in the cells. Gao et al. [85] used quantum dots to locate and image
tumors in vivo. They coated quantum dots with a layer of polymer NPs and
polyethylene glycol, and attached them to a prostatic gland specific mono-
clonal antibody. Fluoerescent image analysis revealed multi-color fluores-
cent images that were sensitive to tumor cells in vivo, as well as information
regarding tumor volume and location. Nasongkla et al. [34] performed a
study on polymer micelle loaded with superparamagnetic iron oxide and
found it promising in the dual-targeting delivery and hypersensitive MR in
cancer cells.
Nanomedicine can improve the targeting ability of chemotherapeutic
agents. Rapaport et al. [86] managed to deliver chemotherapeutic agents
accurately into tumor cells using multifunctional NPs which improved the
targeting ability of chemotherapeutic agents and helped destroy cancer
cells effectively. In a recent study was reported that a polyethylene glycol-
phospholipid nano micelle loaded with adriamycin could selectively accu-
mulate in tumor tissue, and penetrate thick layer of tumor tissue. Integrated
quantum dots and glucose-binding protein antibodies selectively recognize
cancer cells. These cells, when irradiated by ultra-violet ray showed green
fluorescence. This strategy allows the differentiation of normal cells and
cancer cells. A prolonged ultra-violet irradiation can eliminate the cancer
cells [87]. Recently, Chakravarty et al. [88] coated a carbon nanotube with
a monoclonal antibody against specific targets on lymphoma cells. When
these “signed” cells were exposed to near infrared light, the carbon nanotube
started to kill these cells by heating them up. A large number of NPs can
serve as carriers of anti-cancer drugs. Drugs incorporated in the nanocarri-
ers, either physically entrapped or chemically tethered, have the potential to
target physiological disorder zones sparing normal cells from collateral con-
sequences. The pharmacokinetic profile, especially the transportation capa-
bilities, of the drug substances have been greatly modified by incorporation
in a nanodrug delivery system. These include enhanced accommodation for
targeting moieties such as chaperones, and alteration in release rates com-
prising of controlled release and site-specific delivery, by use of molecular
engineering techniques. Additionally, encapsulation of the drug substances
in various polymeric and inorganic composites have also been evaluated for
their rationalization of the drug delivery systems. Such encapsulations are
generally made for protecting the biologically active protein and peptide-
based drug compounds from the detrimental effects of biological fluids.
In gene therapy, exogenous genes are introduced into cells by properly de-
signed carriers, so as to cure the disease by correcting the abnormal genes.
