Nanomaterials in Medicine
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form aggregates. The usage of carbon nanotubes in medical applications ranges
from diagnostics to therapeutics. Examples include cancer therapeutics, gene
therapy, infection control and antimicrobial therapy, tissue regeneration, treating
neurodegenerative disorders, and NIR (Near-infrared) fluorescence microscopy.
Industries make carbon nanotubes with allographs of carbon—graphite by the
process of chemical vapor deposition. This chemical manufacturing process arranges
carbon atoms hexagonally in tube-like structures. There are two types of carbon
nanotubes based on the number of layers—single-walled and multi-walled carbon
nanotubes. Carbon nanotubes can easily cross the cell and nuclear membranes to
deliver the drug in exact location without losing concentration. So scientists use
carbon nanotubes as drug carriers to deliver exactly to the tumor cells. They have
combined carbon nanotubes with many anticancer drugs and successfully tested both
in vitro and in vivo, such as epirubicin, doxorubicin, and paclitaxel [2]
Studies show the usage of carbon nanotubes in antitumor immunotherapy [3].
They used a tumor vaccine or antigen in a carbon nanotube carrier to stimulate the
body’s immune system to attack tumor cells. They combined the tumor antigen with
the carbon nanotube as a natural antigen-presenting cell to bring about the efficacy
of the immune effector cells.
Carbon nanotubes, among other materials, are the best-suited candidate for tissue
engineering. Carbon nanotubes are biocompatible, non-biodegradable, and functionalized with biomolecules for tissue regeneration. Since carbon nanotubes have strong
mechanical properties, it reinforces tissue scaffolding and better conductivity with
the host. Researchers use carbon nanotubes as labeling and imaging agents for their
remarkable optical properties.
3 Liposomes
In 1970, Gregoriadis introduced liposomes as a drug delivery vesicle. A liposome is a small spherical vesicle filled with water, its size ranging from 30 nm
to several micrometers. Liposomes are artificially made from cholesterol and phospholipids. Liposomes have several exploitable properties like size, hydrophobic, and
hydrophilic walls, which make them suitable for drug delivery systems. Liposomes
are made with either rigid or fluid vesicles based on the choice of the bilayer components; for example, unsaturated phospholipids from natural sources give more fluid
and permeable bilayers.
In contrast, saturated phospholipids make it a rigid and impermeable bilayer [4].
Scientists use liposomal encapsulation technology to deliver drugs to the target body
organs. They encapsulate active drug components inside these liposomes, which
form a barrier around the drug. Liposome encapsulated drugs make the drug highly
available in the body and protected from further chemical reactions like oxidation and degradation. Liposomes have low efficiency in holding hydrophilic drugs.
Medications using liposomes as carriers are available as analgesics, anticancer, and
antifungal drugs.
199
form aggregates. The usage of carbon nanotubes in medical applications ranges
from diagnostics to therapeutics. Examples include cancer therapeutics, gene
therapy, infection control and antimicrobial therapy, tissue regeneration, treating
neurodegenerative disorders, and NIR (Near-infrared) fluorescence microscopy.
Industries make carbon nanotubes with allographs of carbon—graphite by the
process of chemical vapor deposition. This chemical manufacturing process arranges
carbon atoms hexagonally in tube-like structures. There are two types of carbon
nanotubes based on the number of layers—single-walled and multi-walled carbon
nanotubes. Carbon nanotubes can easily cross the cell and nuclear membranes to
deliver the drug in exact location without losing concentration. So scientists use
carbon nanotubes as drug carriers to deliver exactly to the tumor cells. They have
combined carbon nanotubes with many anticancer drugs and successfully tested both
in vitro and in vivo, such as epirubicin, doxorubicin, and paclitaxel [2]
Studies show the usage of carbon nanotubes in antitumor immunotherapy [3].
They used a tumor vaccine or antigen in a carbon nanotube carrier to stimulate the
body’s immune system to attack tumor cells. They combined the tumor antigen with
the carbon nanotube as a natural antigen-presenting cell to bring about the efficacy
of the immune effector cells.
Carbon nanotubes, among other materials, are the best-suited candidate for tissue
engineering. Carbon nanotubes are biocompatible, non-biodegradable, and functionalized with biomolecules for tissue regeneration. Since carbon nanotubes have strong
mechanical properties, it reinforces tissue scaffolding and better conductivity with
the host. Researchers use carbon nanotubes as labeling and imaging agents for their
remarkable optical properties.
3 Liposomes
In 1970, Gregoriadis introduced liposomes as a drug delivery vesicle. A liposome is a small spherical vesicle filled with water, its size ranging from 30 nm
to several micrometers. Liposomes are artificially made from cholesterol and phospholipids. Liposomes have several exploitable properties like size, hydrophobic, and
hydrophilic walls, which make them suitable for drug delivery systems. Liposomes
are made with either rigid or fluid vesicles based on the choice of the bilayer components; for example, unsaturated phospholipids from natural sources give more fluid
and permeable bilayers.
In contrast, saturated phospholipids make it a rigid and impermeable bilayer [4].
Scientists use liposomal encapsulation technology to deliver drugs to the target body
organs. They encapsulate active drug components inside these liposomes, which
form a barrier around the drug. Liposome encapsulated drugs make the drug highly
available in the body and protected from further chemical reactions like oxidation and degradation. Liposomes have low efficiency in holding hydrophilic drugs.
Medications using liposomes as carriers are available as analgesics, anticancer, and
antifungal drugs.