Session C1
Paper 221
Disclaimer—This paper partially fulfills a writing requirement for first year (freshman) engineering students at the University
of Pittsburgh Swanson School of Engineering. This paper is a student, not a professional, paper. This paper is based on publicly
available information and may not provide complete analyses of all relevant data. If this paper is used for any purpose other
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MAGNETICALLY TRIGGERED DRUG DELIVERY SYSTEMS TO IMPROVE
CHEMOTHERAPY TREATMENTS
Teddi Sedlar, [email protected], Mena 1:00, Sean Tighe, [email protected], Mena 1:00
Abstract-One of the biggest problems in treating major
diseases is the need to deliver the necessary treatment to the
specific tissue in the body. For example, chemotherapy is an
effective cancer treatment, but it is known to cause
unfavorable side effects such as nausea, hair loss, and
fatigue. This is largely because the chemicals which destroy
the cancer cells migrate to other parts of the body and
damage the healthy cells. Researchers in drug delivery
systems seek to overcome obstacle like this by improving
specificity in targeting the diseased area of the body, which
would decrease side effects and lower the amount of drug
required for treatment.
This paper will focus on the use of magnetic fields to
guide and trigger the release of drug delivery systems in the
human body. These systems are usually nanoscale hydrogels
with embedded ferromagnetic particles which encase the
drug. Exposure to alternating magnetic fields causes the
ferromagnetic particles to rotate in place, which facilitates
release of the drug and also creates heat. The heat caused by
this reaction can act therapeutically, as cancerous tissues
lack the vascular systems that healthy tissues have, which
allow the healthy tissue to dissipate heat more efficiently. This
technology has the potential to improve the sustainability of
cancer treatment by supplementing already existing
treatments, but it poses some concerns such as the improper
release of drug inside of the body.
because the stomach or gastric system must break down or
otherwise absorb the chemicals in the herbs to effectively help
the patient; however, one must inject epinephrine into muscle
tissue so that the body properly absorbs and incorporates the
hormone, but injecting it into a vein may kill the person
treated.
In recent history, we have rapidly advanced drug
delivery systems (DDS) from herbal teas, to pills, injections,
and even to radiation and electromagnetism treatments. Each
of these methods was developed to deliver newly designed
drugs so that patients and their doctors may access a variety
of treatments. One of the most recent developments in drug
delivery technology is the use of magnetic fields to guide
nanoparticles to the area of the body undergoing treatment,
and also using these magnetic fields to release the drug locally
in the body.
A core goal of developing these systems is to increase
the quality of life for the patient by avoiding some of the side
effects caused by other treatment methods. Increasing the
quality of the patient’s life is the most important aspect of
sustainability (the balance between something serving the
needs of present generations as well as those of the future).
This is particularly important for cancer patients, who can
experience a deluge of physical and psychological problems
resulting from the cancer and from its treatment. This new
approach seeks to prevent the side effects of drugs by
targeting a specific area, while treating the condition at its
source.
Key words- drug delivery, cancer treatment, hydrogel,
magnetic release, magnetic triggering
SYNTHESIS OF MAGNETIC DDS
OVERVIEW OF DRUG DELIVERY
SYSTEMS
One common form of magnetic DDS is that which has a
hydrogel coating surrounding the drug, while embedded with
ferromagnetic particles. A hydrogel is a polymer which has a
distinct three-dimensional shape and is partially comprised of
water. There are many ways to synthesize the hydrogel
coating, most of which involve cross-linking the individual
polymer molecules.
A polymer is a large molecule that is made mostly of a
single element, usually carbon because of its unique ability to
form four bonds. Each carbon atom is bonded to two other
For centuries, people have used and continue to use
drugs to treat, cure, or prevent diseases, whether as herbal
tisanes to ease nausea, or as epinephrine injected to reverse
anaphylaxis. Different drugs have different chemical
compositions and properties which allow them to treat
different diseases. Because of these varying properties,
different types of drugs require introduction to the affected
area in different ways. For example, tisanes are ingested
University of Pittsburgh, Swanson School of Engineering
Submission date: 03.03.17
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Sean Tighe
carbons and up to two other atoms. These polymers can
branch off into functional groups such as amino acids, and
when a cross-linking agent is introduced, it catalyzes a
reaction between the polymer chains or their functional group
branches which makes them bond together. If there are more
polymer chains bonded together, the polymer becomes more
viscous, until it becomes a semi-solid ‘slime,’ or hydrogel.
There are many different kinds of polymers, and some are so
common children can buy kits to make these hydrogel
‘slimes.’ The kits usually contain polyvinyl acetate, (the
liquid polymer) and borax, which is a salt of boric acid and
acts as the cross-linking agent.
Hydrogels used for drug delivery involving magnets are
synthesized to have the ferromagnetic particles embedded in
them by introducing the magnetic nanoparticles (MNPs) into
the polymer solution to cross-link the hydrogel, although
there are many other ways to do this. Hydrogels are unique
because they are able to absorb water without dissolving in
water, and the quantity of water absorbed can be influenced
by stimuli such as changes in temperature or pH. The amount
of water that they can absorb is given by the equation:
Water Uptake = (Ws- Wd)/ Wd x100
EQUATION 1 [1]
where Ws is the weight of the swollen hydrogel at equilibrium
and Wd is the initial weight of the dried hydrogel. The ability
for hydrogels to absorb liquid without dissolving in it is of use
to the development of magnetically controlled DDS, as this
property allows them to serve as carriers for the drugs
undergoing transportation [1]. In fact, introducing the drug to
the hydrogel occurs by allowing the dry hydrogel to soak in
the liquid drug, thus allowing the hydrogel to store the drug
between the polymer molecules.
unpaired electrons are forced to spin in the same direction,
which causes the material to become a magnet. The magnetic
nanoparticles involved in this technology are all
ferromagnetic [2].
When a magnetic field is applied which rapidly changes
direction, it causes the individual atoms to also rapidly change
direction so that they can align themselves with this field. So,
if a ferromagnetic atom is initially not magnetic, then a
magnet is applied whose field points to the left, the atom will
become magnetized and its field will point to the left. Then,
if the field changes directions and points to the right, the atom
must spin around so that it points to the right as well. These
rotations deform the hydrogel, which aids the diffusion of the
drug out of the structure and into the body, as demonstrated
in figure 1.
FIGURE 1 [3]
Cells with internalized hydrogels containing MNPS
The rotations also cause an increase in temperature,
which also helps to deform the hydrogel coating. This
magnetic heating can also act as its own treatment because
cancerous tissues commonly do not have the proper vascular
tissue to diffuse heat as healthy cells do. Thus, heating to
approximately 45 degrees Celsius can kill cancer cells
without harming the neighboring healthy cells. As the
hydrogel stretches and deforms, it releases the MNPs as well
as the drug, and both are then absorbed by the cell. Thus,
when the MNPs rotate, they heat up the liquid inside of the
cells; this conversion of magnetic potential energy to thermal
energy is called Néel relaxation. Figure 1 demonstrates how
hydrogels engulfed by cells release their payload into the cell.
“Heat generation through Néel relaxation is due to rapid
changes in the direction of magnetic moments, hindered by…
energy that tends to turn the magnetic domain of the magnetic
nanoparticle in a given direction according to their crystal
lattice structure” [3].
Magnetic accumulation of MNPs in the human are
described using the following formulas:
F = 4/3 π b^3 (M⦁𝛁) H
EQUATION 2
F = 6 π η r (v -v )
EQUATION 3
wherein F is the magnetic force, b is the radius of the
magnetic particle, M is the magnetization of the magnetic
particle, H is the external magnetic field, η is viscosity, v is
fluid velocity, F is drag force, v is particle velocity, and r is
particle radius, and 𝛁 represents the gradient of the field [4].
To guide the hydrogel against the flow of blood in a blood
PHYSICS OF MAGNETIC DDS
These embedded particles allow a constant magnetic
field to direct these nanoscale hydrogel/drug complexes,
while the main release of the drug is triggered when an
alternating field is applied.
All atoms have a cloud of electrons surrounding them,
and each electron is spinning in a certain direction according
to quantum mechanical laws. This electron spin is what
causes magnetic field. Electrons prefer to ‘pair up’ when close
together by spinning in opposite directions, which usually
cancels their magnetic field contributions, which is why most
materials are not magnetic. However, if there are unpaired
electrons, the magnetic field contributions do not cancel,
which causes magnetism. If there are multiple unpaired
electrons, a particle may still have zero magnetism if the
electrons are spinning in opposite directions.
Ferromagnetism, however, is the attribute which allows
non-magnetic material to become magnetized and experience
attraction to a magnet. When a magnetic field is applied, the
M
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f
p
M
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Teddi Sedlar
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vessel, the force exerted by the magnet must surpass the force
exerted from drag, so F > F . The equations show that the
magnetic force is increased with an increased MNP size, but
the drag force is increased with an increased hydrogel particle
size. Therefore, it is important to find a balance between the
size of the MNPs and that of the hydrogel so that the system
can work at the lowest possible magnetic field, and thus the
lowest possible energy input.
“When magnetic nanoparticles are placed in an oscillating or
alternating magnetic field (AMF),… they [generate] heat in
the surrounding medium; therefore, they have been
extensively used for the selective heating of tumours
(hyperthermia)… a broad range of actuation mechanisms for
on-demand drug release has been developed. Typical
examples are the use of thermosensitive polymers and lipids,
which can serve as coating materials for magnetic
nanoparticles and trigger the release of a drug in an on–off
fashion in response to a magnetically induced increase of
temperature… The release of the encapsulated drug can be
modulated by the duration of the AMF on–off states” [5].
Hysteresis loss is the energy dissipated as heat caused
by the changing the magnetization of a particle. This energy
loss happens in the context of this technology because
ferromagnetic particles are not magnetic initially, they are
magnetized by the use of a permanent magnet. For example,
two pieces of iron do not attract each other normally, but if a
magnetic field is applied to them, they can become induced
magnets. However, if a magnetic field of opposite direction is
then applied, it would reverse the polarity of the magnets,
which would cause hysteresis loss. This thermal energy is
what is used in hyperthermia treatments to kill the cancer
cells. This quote also mentions that the drug release can be
turned “off” once it has been turned “on,” which is an
important feature to note, as it may not always be desirable
for all the drug to be released at one time.
M
without causing egregious side effects, which would infringe
on the patient’s quality of life
D
FIGURE 2 [7]
A chart comparing the suitability of iron, cobalt,
and nickel in biological systems
There is also the possibility of the magnetic
nanoparticles harming the human body. Many ferromagnetic
substances can poison people, such as chromium, gadolinium,
and iron. Many heavy metals such as these are toxic because
they interfere with the neurons throughout the body and block
or alter the transmission of signals between the brain and the
rest of the body. However, iron is part of many magnetic
nanoparticles used in vivo because iron toxicity only occurs at
concentrations of about 10-20 milligrams of iron per kilogram
of bodyweight [7]. It is highly unlikely that a single dose of
magnetically triggered drug therapy could even come close to
5 mg because of the relative size of the delivery systems and
the magnetic particles to the human body. Iron has a low
toxicity because it is a fundamental aspect of the human diet,
as it aids oxygen transfer in red blood cells. Many patients
would pass any excess iron not used by the body before a
second dose could be administered, usually in about a day.
Types of Magnetic Nanoparticles
APPLYING MAGNETIC DRUG DELIVERY
SYSTEMS IN CANCER TREATMENT
There are a variety of magnetic materials that have
potential uses in the creation of drug release systems; three
examples include iron, cobalt and nickel. Of the three, iron is
the most effective for drug delivery, as it is easily directed
throughout the body and the polymers containing it are easily
condensed by the magnetic fields when compared to the other
two. Systems containing iron can also be easily “loaded” with
the drugs used, and can release a large amount of the drug at
the target site with far less damage to nearby tissue than in the
case of nickel or cobalt. Iron avoids harming the nearby
tissues in multiple ways; for example, in brain cells, iron does
not show increased toxicity despite the passage of time or
increases in concentration. The body can also recycle iron,
and incorporated into proteins like ferritin. Because of these
traits, iron is a very favorable magnetic nanoparticle for
suspension in the hydrogels [6]. This all coalesces to indicate
that the magnetic component of the DDS can be implemented
The main characteristic of a cancer cell is that it lacks
the proper mechanisms to function correctly, and the part of
the cell meant to prevent these defective cells from replicating
has undergone damage, which in turn results in the buildup of
defective cells that harm the source body. The standard life
cycle of a cell is that it grows to a certain size, and then
divides. During this cycle, the cell may die because of disease
or other natural causes. Sunburn can cause such damage to
which causes cancer, as exposure to ultraviolet light damages
the genetic material, deoxyribonucleic acid (DNA). If the
DNA is damaged, the cell attempts to repair it; if the cell fails
to do so, it produces enzymes which cut up the DNA as well
as the cell itself to prevent the damaged DNA from
reproducing. Cancerous cells do not produce these enzymes,
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so the damaged DNA can reproduce. This causes the
‘daughter cells’ to make the wrong proteins and perform the
wrong functions, which may hinder the ability of the
organism to go about daily tasks.
Stopping cancer cells from reproducing and preventing
the diseased tissue from spreading is a major part of treating
cancer. These cells tend to carry other defects that prevent
them from fulfilling their role in the body, but they still use
the body’s energy to replicate, and unchecked proliferation
may eventually kill the person suffering from the cancer.
However, cancer is more difficult to treat than many other
diseases since cancer cells are extremely similar to those of
the patient, so whatever can kill the cancer can usually also
kill the patient, whereas penicillin can kill a bacterium but not
a person. The goal of many cancer treatments is, therefore, to
kill as many cancerous cells as possible while killing the
fewest amounts of healthy cells. This goal is the crux of
magnetic DDS’s purpose; to continue to effectively treat the
cancer while limiting the damage to the rest of the patient’s
body.
Another form of cancer treatment is the surgical removal
of tumors, but this is not affective when a tumor is in an
unreachable region of the body. An article from the journal
Nature Materials by researchers at the University of Southern
Paris explains how magnetic DDS could reach these regions,
as well as some the new technology’s own imperfections:
“The use of magnetically responsive nanoparticles, either for
magnetic guidance or local hyperthermia, is generally limited
to accessible tumour nodules, but not metastasis or
disseminated tumours. Even if most of these tumours are
indications for direct surgery, some are not surgically
removable… In these situations, magnetically responsive
nanoparticles represent a promising therapeutic option.
However, magnetic guidance is hampered by the complexity
involved in the setup of external magnetic fields, which need
adequate focusing and deep penetration into the tissues to
reach the diseased area with sufficient strength” [5].
As these researchers explain, even though magnetic
DDS can improve cancer treatments through increasing the
efficacy of targeting the cancer cells during treatment, this
increased specificity makes this form of improved
chemotherapy improper for cancer which has a high rate of
metastasis. Metastasis is the process by which individual
cancer cells break free from their tumors and circulate
throughout the bloodstream, then fixing themselves in a new
spot in the body and forming new tumors. Because a limited
amount of the drug will circulate through the body, areas that
are not yet confirmed as cancerous cannot undergo treatment
at the same time as the known cancer. Thus, specificity is not
always desirable in treating cancer. However, if the patient
has a tumor in an area of the body that is hemorrhagic (prone
to excessive bleeding) or in an area where to access the tumor
via surgery would mean harming sensitive tissues, magnetic
hydrogels can reach to these places instead.
Another problem noted by this explanation is that this
system of drug delivery has not yet had much research done
on it, and will not move on to clinical trials for many years.
However, when this technology is perfected, it will show a
large degree of efficacy because the magnetic fields used in
this technology can penetrate tissues very well, so tumors near
the surface of the body can undergo treatment as easily as
those deeply embedded in the patient.
Mitotic Inhibitors as a Model Drug
These drug delivery systems can treat cancer more
efficiently than standard techniques in some cases.
Chemotherapy involves introducing poison into the patient
orally or through injection with the intent to kill the cancerous
tissue; however, as noted previously, the chemicals also harm
the patient, causing terrible nausea and other side effects [8].
One other category of anticancer drug is mitotic inhibitors,
which “are compounds derived from natural products, such as
plants. They work by stopping cells from dividing to form
new cells but can damage cells in all phases by keeping
enzymes from making proteins needed for cell reproduction.
Examples of mitotic inhibitors include: Docetaxel,
Estramustine,
Ixabepilone,
Paclitaxel
Vinblastine,
Vincristine, [and] Vinorelbine They are used to treat many
different types of cancer including breast, lung, myelomas,
lymphomas, and leukemias. These drugs may cause nerve
damage, which can limit the amount that can be given” [9].
The mitotic spindle is integral to mitosis, the process by
which cells grow and divide. It is an organelle which aids in
the separation of genetic material in the form of chromosomes
to two ends of the cell, so that when the cell divides, each half,
or ‘daughter cell’ has the same amount of genetic information.
By inhibiting the enzymes which form these organelles, these
drugs ensure that the cells affected cannot finish their life
cycle and reproduce, so instead they just die.
At the same time, preventing the cells from continuing
to divide cannot reverse the cancer, as the cancerous cells also
do not undergo apoptosis appropriately, also known as
programmed cell death. When a cell’s DNA is damaged
beyond repair, enzymes are created which destroy the cell so
that the rest of the organism is protected from this faulty
DNA. However, cancer cells lack this ability, and instead
usually live much longer than normal cells of the same type.
Therefore, even more chemicals must be used which actually
kill the cancer cells. These also have the potential to kill
healthy cells if the drug attacks them instead.
Of course, current chemotherapy has methods by which
to make the drugs affect only the cancerous cells, but these
can fail, as can the magnetically guided hydrogel system.
Magnetic DDS is not designed to replace current
chemotherapy methods, only to improve it. Magnetic drug
delivery systems are capable of working in conjunction with
other methods of targeting to more efficiently target the
cancer cells by undergoing magnetic direction to the spot
where the cancer is located as described above. This targeting
also allows a doctor to give less medicine to attain the same
effect. For example, “the 𝛂-COOH of folic acid (FA)
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specifically binds to folate receptors (FRs) overexpressed in
breast cancer tumors… and therefore, FA-modified MNPs
without the loss of 𝛂-COOH can selectively target tumors”
[10]. This means that one can use the MNPs to guide the drug
to the cancerous tissue, which in this case is the breast tissue,
and then the hydrogel will bond predominantly to the cancer
cells and release the drug mostly into the cancer cells. Some
of the hydrogel particles will still bond to the healthy cells as
well, but since the cancer cells have more folate receptors,
more hydrogel particles will bond to the cancer and thus
release more drug into the cancer cells.
Once again Mura explains:
“The advantage of using a magnetic field relies on the
different nature that the magnetic response can take, which
can be a magnetic guidance under a permanent magnetic field,
a temperature increase when an alternating magnetic field is
applied, or both when alternately used. Therefore,
magnetically responsive systems allow for diversity in the
drug-delivery pathway… This concept has demonstrated
great potential… because of improved drug accumulation
inside solid-tumour models. Candidate nanosystems for such
a therapeutic approach are core–shell nanoparticles (a
magnetic core… coated with silica or polymer), …
nanocrystals encapsulated in ... Most core–shell nanoparticles
have shown promising results in vitro, yet only some of them
have demonstrated improved tumour accumulation and
anticancer pharmacological efficacy in various in vivo
models. However, without normalized benchmark
experiments, the comparison between all these systems
remains rather difficult” [5].
Once the drug is at its destination, an alternating
magnetic field is applied so that the hydrogel heats up and
deforms. The deformation releases the drug at a high rate, and
the heating, if it reaches the critical temperature, can
kill/harm/weaken the cancer as well.
From start to finish, the process can be described simply
as such: A hydrogel is made by introducing a liquid polymer
to a crosslinking agent in the presence of a magnetic
nanoparticle such as iron. The hydrogel forms around the
MNPs in a process called emulsion. Next, the hydrogel is
soaked in a liquid drug which is known to treat cancer, such
as the mitotic inhibitor Docetaxel. A medical professional
then injects the hydrogel system into the patient near the site
where the tumor is known to be. A static magnetic field is
used to guide the hydrogel to the precise location where the
drug needs to be delivered.
For increased accuracy of treatment, the outside of the
hydrogel may have different kinds of molecules attached to
the outside, such as folic acid in the case of treating breast
cancer. Once the hydrogel is exactly where it needs to be, the
magnetic field is made to oscillate rapidly, which causes the
MNPs to rotate in place, which deforms the hydrogel and
causes the release of the drug. If necessary, the release can be
turned off by stopping the oscillation of the field and replacing
it with a static field once more. This allows the release of the
drug to be controlled both temporally and spatially.
This increased accuracy of targeting decreases the
amount of drug which is available to affect healthy tissues,
which decreases side effects and increases quality of life.
However, even when the release is turned ‘off,’ the drug is
still being released at a much lower rate than normal because
it is still diffusing through the nanoscale pores in the gel. So,
even though this technology improves drug release
specificity, the process is still not perfect. Because of this
imperfection, a patient may still feel the side effects of
chemotherapy as in a traditional chemo session, but they
should be much less pronounced.
The competing positives and negatives discussed here
are just a handful of examples of the many ramifications
found during cancer treatment. This is a complex issue, and
doctors must keep all of them in mind in order to find the best
treatment for a particular patient. Magnetic DDS can offer one
solution to the problems caused by the other treatments listed
here. That said, this new advance does have its own
drawbacks.
PROBLEMS WITH THIS TECHNOLOGY
Although this technology can positively impact many
lives, there are also several drawbacks that we must consider.
Because of the concentration gradient between the inside and
the outside of the hydrogel capsules, a small amount of the
drug will leak out, which is unavoidable. With improved
technology, however, having the DDS in the body when it is
actively in use, such as at a chemotherapy session could help
to alleviate this. But how can we make sure that all of the drug
has been used by the end of the session?
One other problems with this technology is that much
more research is necessary clinical trials can proceed, because
there is still much about this technology that we do not
understand. Since the integration of magnetic nanoparticles
increases the release of the drug when a magnetic field is
introduced, one would think that a greater number of
magnetic nanoparticles in a sample of hydrogel would
increase the release of drug even more. However, at certain
strengths of field, increasing percent of MNPs can actually
decrease the rate of release. In a recent study, Marianna Uva
and a team of researchers tested the release of a model drug
from a pure hydrogel compared to that of a hydrogel with 50%
w/w MNP and a hydrogel with 70% w/w, where w/w denotes
weight of the MNP compared to that of the total
MNP/hydrogel complex. It was found that the ferrogels
released less than the control hydrogel which did not have
MNPs under a static field, which is the type of field which is
used to guide the system [1].
When a strong magnet which had a high frequency of
oscillation was applied, both ferrogels released more than the
standard hydrogel. However, when a weak magnetic field
with much higher frequency was used, the 50% ferrogel was
much more effective in releasing the drug, while the 70%
ferrogel was equally effective as the unchanged hydrogel.
Researchers concluded that in the 70% ferrogel, the MNPs
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Control “Each year in the United States, 60,000 cancer
patients are hospitalized because their low white blood cell
count led to a serious infection. One in 14 of these patients
dies” [11]. For a chemotherapy patient, even a slight fever has
to be deemed a medical emergency. Patients also can see their
relationships affected by this, as anyone who may be ill has to
be kept at a distance from the patient, thereby lowering the
patient's quality of life.
Some cancers are also treated with bone marrow
transplants, whereby a patient has stem cells introduced into
their body, either collected from the patient or donated from
another person, but there are a variety of side effects. Antirejection drugs used to keep the patient from rejecting the
transplant can lower the patient’s immune system, and
transplants can also attack the patient’s body, putting further
strain on the patient. Surgery to remove tumors can also harm
the quality of life for a patient, such as how the removal of a
part of or all of the pancreas to treat cancer in that organ can
result in the patient developing diabetes. Giving a patient
diabetes would worsen their quality of life because they
would then require insulin as well as chemotherapy following
the procedure. However, the insulin injections and blood
sugar monitoring would continue throughout the rest of the
patient’s life. Magnetic DDS have no risk associated with
them of giving the patient such complications, and are
therefore preferable in this aspect.
Magnetically targeted drug delivery systems have the
potential to lower the prevalence of the use of these other
methods of cancer treatment. By only targeting the necessary
areas of the body, doctors can prevent chemotherapy from
attacking the white blood cells, which are vital to the
prevention of infection. In doing so, the patient will have a
better chance of avoiding the deadly infections that kill over
4000 patients every year. Cancer treatments can also vary
between patients depending on age, the type of cancer, and
other variables. Magnetically triggered drug delivery systems
will add another tool to the toolkit of doctors, and may very
well prove a viable alternative to the treatments with more
dangerous side effects. So, while the ethical concerns of
implementing magnetically triggered drug delivery systems
as stated above are of note, the ethical concerns of the
preexistent treatments indicate that their utilization is a matter
of balancing the possible downfalls of treatment on a patientby-patient basis, and that this new method of delivering the
drug gives a greater variety of treatment for the patient.
cluster together and block the drug from escaping from the
gel. This is a problem because more research is required to
find the ideal ratio of mass of MNP to mass of the gel.
It is also important to note that magnetic fields can cause
pacemakers to beat out of the usual rhythm which cause issues
for the patient’s health [12]. A pacemaker is a device which
assists or completely replaces the patient’s heart’s ability to
beat regularly. One can imagine how detrimental it would be
for a cancer patient to not have a functioning heart because of
their chemotherapy. If the cancerous tissue is not directly
adjacent to the pacemaker, the ‘reprogramming’ of the device
can be avoided. However, in other cases, magnetic fields
cannot be applied to the cancerous tissue, so another method
of drug delivery must be applied.
Clinical Trials and Hitting the Market
While the treatment remains in its clinical testing stage,
the patients do not need to pay for it, as it is covered by the
agency which is funding the research. Prior to the clinical
trials, patients must not be preferentially treated based on
income or any other criteria not related to the study.
Researchers must also ensure that the patients are not
volunteering for the trial solely because they believe it is the
only way that they will get treatment, nor can they believe that
they will definitely be cured of their cancer. There are many
more factors to consider in clinical trials
Another problem faced by any new medical technology
is: who is going to pay for this once it is out of clinical trials?
How will insurance agencies reallocate their resources to
allow for people to get this brand-new treatment, if the
insurance companies decide to pay anything at all? The
clinical testing stage would have to prove the technique to be
at least as effective at treating cancer as traditional techniques
to proceed to the general market, but insurance companies
may be wary of new technologies. It is extremely important
that this technology does well in its clinical testing because
all cancer treatments and related hospital expenses are very
expensive when paid for out of pocket. Even though the
magnetically triggered release system may be more
sustainable by increasing patient quality of life as outlined
below, insurance companies and some of their patients may
still feel uncomfortable with this.
BENEFITS OF USING MAGNETIC DDS
COMPARED TO TRADITIONAL CANCER
TREATMENT
MAGNETIC DRUG DELIVERY HAS MUCH
POTENTIAL
Traditional cancer treatments have been shown to be
effective in many cases, but their side effects can reduce the
quality of life of the patients being treated. For example,
chemotherapy can kill off cancerous cells, but it is also known
to lower a person’s immune system, and sometimes the
infections which take advantage of this weakness kill the
patient before the cancer. According to the Center for Disease
Unlike diseases caused by outside influences, such as
bacteria and parasites, cancer is a far greater threat to the
human body because cancer cells are similar to healthy cells,
to the extent that anything that can kill the cancer can and
oftentimes will result in the death of healthy cells, which can
in turn restrict or halt the function of organs and tissues vital
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Sean Tighe
[8] “Understanding Chemotherapy.” American Society of
Clinical
Oncology.
2017.
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for survival. Rather than attempting to create drugs that are
less deadly to human cells and therefore reduce efficacy, the
approach of magnetically triggered drug delivery systems
allows us to use the already developed drugs and concepts
behind treatments such as hyperthermia and radiation therapy,
but limit their effect to only areas of the body that require this
treatment. This method incorporates the use of magnetic
materials in conjunction with hydrogels in order to both draw
the drugs to the location of the tumor and release the drug only
when this location is achieved. While this research is still
being developed, and will require further study to be properly
implemented, the promising nature of this technology ensures
that it will change the nature of cancer treatment, and improve
the quality of life for those who suffer its effect.
ACKNOWLEDGEMENTS
We would like to thank our respective families for
supporting us through our first year of university education.
This conference would not be possible without you, because
we would not be here to give this presentation.
We would also like to thank the writing instructors and
the students who read and reviewed our paper, your critiques
were greatly appreciated and extremely valuable.
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