Vol 10, Issue 6, 2017
Online - 2455-3891
Print - 0974-2441
MAGNETIC MICROSPHERE AN EMERGING DRUG DELIVERY SYSTEM
DIKSHA SHARMA*, ABHISHEK SHARMA
Department of Pharmacy, L. R. Institute of Pharmacy, Solan, Himachal Pradesh, India. Email: sharma25pharmacy@gmail.com
Received: 24 January 2017, Revised and Accepted: 06 March 2017
ABSTRACT
The drug delivery system has been advanced to release the drug according to the body requirement during the entire period of treatment and also
for the delivery at the targeted site. Several novel drug delivery systems have emerged encompassing different route of administration to achieve
controlled and targeted drug delivery, magnetic microsphere carrier being one of them. Magnetic microsphere is an alternative to traditional radiation
methods. As the traditional radiation methods use highly penetrating radiation that is absorbed throughout the body and cause side effects hence its
use is limited. Therefore, a safe and effective alternate is needed like magnetic microsphere. The excessive circulating drug particles are minimized by
this delivery system. Moreover, the aim of specific targeting is to enhance the effectiveness of drug delivery and at the same time to lessen the toxicity
and side effects. Magnetic carriers receive magnetic responses to a magnetic field from incorporated materials that are used for magnetic microsphere
are chitosan, dextran, etc. One of the most utilized magnetic microspheres is serum albumine whether from human or other suitable animals. Drug
release from the albumin microsphere can be controlled by various stabilization procedures. Overall, the targeted magnetic microsphere is much
valuable novel drug delivery system for what more work have to be done. By knowing the importance of all this, the present paper reviews the
mechanism, preparation, and applications of magnetic microspheres. As the targeted drug delivery system implies selective and effective localization
of drug into the target at therapeutic concentrations with limited access to non-target sites. Magnetic microspheres hold great promises for reaching
the goal of controlled and site-specific drug delivery.
Keywords: Magnetic microspheres, Targeted drug delivery, Target sites, Body, Radiation, Efficiency, Toxicity, Reduce side effect.
INTRODUCTION
Extensive labors have been dedicated in recent years to utilize potential
pharmaceutical devices like novel drug delivery systems. Design and
development of novel drug delivery system have two basics. First, it
should distribute the drug in accordance with a predetermined rate, and
second, it should release therapeutically effective quantity of drug at the
site of action [1,2]. Conventional drug delivery undergoes from several
drawbacks such as increased variation in the circulatory drug level, extra
frequency of dosage administration, increased gastrointestinal irritation,
and dose-related side effects. To solve these disadvantages, controlled
release drug delivery systems have been planned for even and constant
drug release over a prolonged period [3]. The steady drug release is
achieved by use of different kinds of polymeric systems; biodegradable
polymer microspheres are one of the most common types which are used
as a targeted drug delivery systems. Microspheres can encapsulate many
types of drugs with small molecules, proteins, and nucleic acids are easily
administered through a syringe needle. They are normally biocompatible,
can give high bioavailability, and are capable of constant release for long
periods [4]. Magnetite offers a large potential for innovation in electronics,
optoelectronics, magnetic storage, biomedical, Ferrofluid, separation,
and magnetically guided drug carriers for targeting the therapy [5].
Magnetic microsphere is small particle, with diameter in the micrometer
range (1-1000 µm). Magnetic microsphere is occasionally referred
to as microparticles. Magnetic polymer microspheres are generally
composed of magnetic cores to make sure for strong magnetic response
and polymeric shells to give positive functional groups and protect from
particle aggregation [6]. Small amounts of drug targeted magnetically
to restricted sites can replace large doses of drug that, using traditional
administration methods, freely flow in the blood and beat the target
site in a generalized way only. Moreover, drugs within the sphere
are protected from breaking down during transport. Such drugs are
targeted instead of distributed in blood and do not harm sensitive
organs such as bone marrow. Magnetic microspheres are a substitute
to traditional radiation methods which use extremely penetrating
radiation that is absorbed throughout the body. Its use is limited by
toxicity and side effects. Magnetic radioactive microspheres are applied
in a way similar to non-radioactive spheres. A magnet, placed outside
the body, is directed to the target site. The magnet can be a rod-shaped
permanent magnet of any size or can be contained in equipment that
looks like an open magnetic resonance imaging scanner. The loaded
microspheres are introduced into a blood vessel and in as little as half
an hour; they get collected at the target site to emit radiation which kills
surrounding cancer cells. The remedial action is achieved usually in a
couple of days or weeks depending on the material used. The treatment
can be repeated if required. Spheres are prepared with microscopic
magnetic particles, such as iron [5,6], so these particles can be retained
at the target site by the application of an external magnetic field of
suitable strength. Magnetic fields are supposed to be safe to biological
systems and adaptable to any part of the body.
PRINCIPLES OF MAGNETIC DRUG TARGETING
The principle of this treatment shows that the magnetic drug can be
retained at or made to flow toward the target site by the application
of an external magnetic field. Retention of magnetic carrier at target
site will decrease reticuloendothelial clearance and increase site
specificity [7].
© 2017 The Authors. Published by Innovare Academic Sciences Pvt Ltd. This is an open access article under the CC BY license (http://creativecommons.
org/licenses/by/4. 0/) DOI: http://dx.doi.org/10.22159/ajpcr.2017.v10i6.17284
Review Article