Recently Carbon nanotubes have been designed to be used as a drug delivery It has shown potential in tissue engineering, nuclear targeting, and
drug, protein and peptide drug delivery also. The small nanoscale dimension
and astonishing properties make them a distinctive carrier with a wide range
of promising applications. This review briefly outlines some of the important
biomedical application of carbon nanotubes. In the last few decades

various micro and nanoscale drug carrier systems have been developed in order to
find well-organized and proficient carrier systems for drugs, genes, and antigen
which will assist the targeting and delivering of bioactives into specific and
precise organ, tissues and cells. These diverse drug delivery systems include
microemulsion, multiple emulsions, liposomes, niosomes, nanoemulsion,
microspheres, nanoparticle, resealed erythrocyte and dendrimers. In recent times carbon nanotubes (CNTs) have been designed to be used as a drug delivery carrier.
Carbon nanotubes were discovered by Bacon in the late 1950s. But they were not
fully appreciated at that time. In 1991 Iijima discovered CNTs and proposed it
as an interesting material due to their structural properties1. CNTs
consist of graphite sheets rolled up in to tubular form. These new nanomaterials
belonging to the family of fullerene are the third allotropes of
carbon2. Recently, scientists have also accounted that CNTs hold
potential of a drug delivery systems. The studies have shown that CNTs loaded
with peptides3, proteins4, nucleic acids5 and
drugs6 comprise effective targeting into the cells. Depending upon
the number of graphene sheets, CNTs can be classified as single-wall carbon
nanotubes and multi-wall carbon nanotubes. . Single-wall carbon nanotubes
Single-wall carbon
nanotubes (SWNTs) are made of a single graphene sheet. These are seamless
cylinders, were first reported in 19931. Their diameters range from
about 1 to 2 nm, and their length is usually in order of the micrometers. SWNTs
typically team up to form bundles. These bundles consists hexagonally arranged
SWNTs to form a crystal-like structure

Carbon nano horns and
fullerenes are some structurally related compound to carbon nanotubes. Carbon
nano horns are composed of graphite carbon atom structurally similar to CNTs.
The difference between CNTs and carbon nano horns is that, the latter have an
irregular horn like shape. Fullerene molecules are almost round cages of 60
carbon atoms arranged in interlocking hexagons and pentagons, like the patches
on a soccer ball.

Cellular and nuclear targeting
The endeavor behind targeted drug delivery is to enhance
the efficiency and diminishing the noxious effects. The CNTs can be chemically
surface modified such that ligands can be attached to their surface functional
groups. These ligands which are specific to certain receptors can carry the CNTs
directly to the specific site without affecting on non-target site. On the other
hand diagnostic moieties like fluoroisothiocyanate (FITC) can also be attached
to the CNTs for probing their way to the nucleus.

Carbon nanotubes in peptide delivery
The use CNTs in peptide
delivery has also been done by scientist. Application of CNT as a template for
presenting bioactive peptides to the immune system has been done. For this
purpose, by using a bifunctional linker epitope of virus and amine group of CNT
can be covalently link and immunization can be done. Subsequently the
immunogenic features of peptide–CNT conjugates can be assessed in vivo. In this
way CNTs can achieve high value in peptide delivery also7.