Biomedical Engineering Reference
In-Depth Information
on various parameters such as intensity of the magnetic i eld, rate of blood
l ow and the surface characteristics of carriers.
Gallo
et a
l developed magnetic chitosan microspheres containing
oxantrazole (MCM-OX), an anti cancer drug, for the treatment of brain
tumour [129]. He monitored the level of OX in the brain at er administer-
ing intra-arterial injections of MCM-OX to male Fischer 344 rats under
the magnetic i eld of 6000G for 30 min. As a result, a 100 fold increase
in OX concentrations in the brain at er administration of MCM-OX was
observed as compared to the OX in solution. In a similar study, Chen
et
al
prepared chitosan-bound magnetic nanoparticles loaded with epirubi-
cin, an anthracycline drug used for cancer chemotherapy. h e magnetic
nanoparticles were stable at pH 3-7 and approximately 80% of the drug
was released at er 150-300 min in a biological buf er.
In vitro
experiment
showed the ei ciency of anticancer property of drug loaded nanoparticles
as compared with that of free drugs [130].
Magnetic i eld enhances the cellular ei ciency uptake of the mesopo-
rous silica nanoparticles. h e internalization of M-MSNs (magnetic mes-
oporous nanoparticles) by A549 cancer cells could be enhanced by the
magnetic i eld. h e endocytosis studies indicate that the M-MSNs inter-
nalization by A549 cells is mainly energy dependent pathway, namely
clathrin-induced endocytosis. With the help of magnetic i eld, anticancer
drug loaded M-MSNs induced cancer cell growth inhibition. Delivery of
hydrophilic and hydrophobic drugs through magnetic mesoporus silica
nanoparticles (MMSNs) inhibits cancer cells growth [131].
Recently, a report on the development of drug delivery system for pho-
tosensitive delivery of an anticancer drug campothtecin along with cyto-
toxic cadmium sulphide from a magnetic drug nanocarrier was developed.
During this experiment, core-shell nanoparticles consisting of magnetic
iron-oxide-cores and mesoporous silica shells were synthesized with a high
surface area (859 m
2
g
−1
) and hexagonal packing of mesopores (2.6 nm)
in diameter. h e mesopores were loaded with an anticancer drug camp-
tothecin and the entrances of the mesopores were blocked with 2-nitro-
5-mercaptobenzyl alcohol functionalized CdS nanoparticles through a
photo cleavable carbamate linkage. Camptothecin release from the mag-
netic delivery system was measured by the l uorescence spectroscopy upon
irradiation by the UV light. As a result, treatment of cancer cells with these
drugs lead to the decrease in viability of the cells because of the activity
of capping of CdS nanoparticles. h e capping of Cds nanoparticles and
loaded camptothecin exert an anticancer activity [132].
Transferrin conjugated paclitaxel biodegradable nanoparticle were
also tested in the murine model for treatment of prostate cancer. It was
