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CAPSOSOMES AS A DRUG DELIVERY SYSTEM: A NEW WAY TO TREAT
PHENYLKETONURIA
Stephanie Thornton, [email protected], Vidic 2:00, Michael Zimlinghaus, [email protected], Mahboobin 10:00
Abstract—Capsosomes are an innovative medicine delivery
method which allows for a more controlled and longer-term
release of medication into the body. The structure of a
capsosome consists of subunits containing the medication
surrounded by a semipermeable membrane. This protects the
drug molecules better than traditional pills so that they can
reach their intended target site. The drug molecules
suspended in the subunits of capsosomes are released more
slowly into the body than if the drug were administered in
traditional pill form. One application of this new technology
is in the more effective and economical treatment of
phenylketonuria (PKU). PKU is a metabolic disorder
characterized by a deficiency in the enzyme necessary to
break down the amino acid phenylalanine. The standard
treatment for PKU involves regular doses of the enzyme that
breaks down phenylalanine. This can be very costly, limiting
the quality of care that is available to lower-income families.
New developments in the field of drug delivery mechanisms,
such as capsosomes, are showing promising results by
delivering the necessary enzyme to the body more efficiently
than traditional medication. Because of this, medication
delivery via capsosomes will be required less frequently than
with standard treatment, leading to less money spent by PKU
patients. Once production efficiency is improved through
more research and more widespread use, the cost of enzyme
treatment via capsosomes will be substantially less. This
development could change the way the world treats certain
disorders, like PKU, and improve the lives of many people.
and cofactors, which are used as the primary treatment for
many metabolic and neurological disorders. While most
pharmaceutical research is focused on identifying and testing
new compounds for use as medications, comparatively little
scientific work is being conducted for completely new drugdelivery systems. One of the most promising of the few
methods that are being researched is capsosome-based
medicine delivery. Capsosomes are microstructures built out
of many small subunits consisting of drug molecules
surrounded by a membrane made up of two polar layers of
lipid molecules. Capsosomes are created by stacking the
subunits one on top of the other in a spherical shell around a
silica grain center, which acts as a foundation for the subunits.
This construction technique is known as the layer-by-layer
(LbL) technique. Capsosomes have been developed to
distribute protein-based drugs to patients’ bodies more
effectively by circumventing factors that would normally
decrease the amount of the drug that reaches the target area.
These factors include digestion and denaturation of the drugs
by stomach acid, as well as the drugs binding to non-target
receptor sites on body cells in the bloodstream. If they are
proven to fix these problems, capsosomes will make the
treatment of many diseases less expensive and more efficient.
One disease which could utilize capsosomes for treatment is
phenylketonuria (PKU), a rare metabolic disorder that leaves
patients unable to digest most protein-containing foods.
Because traditional treatment for this disease and others like
it can be very expensive, patients and their families will
benefit from a drug delivery system, such as capsosomes, that
economizes the production and delivery of drugs that are
already in use.
Key Words—Capsosomes, Drug delivery systems, Enzyme
Medication, Metabolic Disorder, Phenylketonuria, PKU
Treatment
INNOVATIVE MEDICINE
THE STRUCTURE AND CHEMISTRY OF
CAPSOSOMES
The predominant ways for patients to receive drugs
under modern medicine are either by taking pills orally or
getting injections intravenously. While both methods have
been proven effective at delivering relatively simple
molecules such as those found in Aspirin, Benadryl, or
Claritin, they are not nearly as effective at delivering proteinbased medications. Medications of this type include enzymes
Both the structure and function of capsosomes are very
intricate in nature. Their structure is perhaps best explained
through an analysis of the processes used to construct them.
Nano-biotechnology researchers led by Frank Caruso at the
University of Melbourne worked on the development of this
micro-container, and the construction is well detailed in their
University of Pittsburgh Swanson School of Engineering
Submission Date 3.03. 2017
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Stephanie Thornton
Michael Zimlinghaus
journal published in Angewandte Chemie International
Edition [1]. The procedure for constructing a capsosome
begins with a microscopic silica grain as a catalyst. The silica
grain is then covered with a polymer coating, known as a
separation layer, that provides a secure surface on which the
first layer of capsules can be anchored. These capsules,
referred to as liposomes, each contain a small amount of
medicine inside them. A typical capsosome will contain
somewhere between three and six layers of liposomes
depending on how high of a drug dosage is required and what
kind of drug is being delivered. A separation layer is also
placed in between each shell of liposomes to keep the layers
intact and to maintain the structural integrity of the
capsosome. At the end of the construction process, a final
capping layer is added to cover the outermost layer of
liposomes, and the silica grain center is removed [1]. LbL
capsosome construction is emerging as the dominant method
of capsosome production in the pharmaceutical industry.
research conducted at University of Melbourne showed why
these steps are necessary and optimize the functionality of the
capsosomes.
Chemistry of Precursor and Separation Layers
Before the first layer of liposomes can be attached to the
silica grain center, a covering made from steroid-based lipids
must be implemented. This first layer, known as the precursor
layer, is meant to provide a strong base layer to which the
liposomes will adsorb, as well as allow the removal of the
silica grain center at the end of the capsosome construction
process. There exist multiple different chemical formulas for
the remaining separation layers used in capsosome
preparation. One of the most promising of these formulas,
developed by C.Y. Yoo and his associate researchers at Seoul
National University of Science and Technology, is a Velcrolike structure that alternates between negatively charged
sodium hyaluronate (HA) chains and positively charged
chitosan molecules, creating a checkerboard pattern of
positive and negative charges [3]. In addition, smaller
liposomes without any drug molecules inside are interspersed
between the positively and negatively charged molecules on
the separation layer. This formula is particularly useful
because it creates a large amount of varied charge along the
surface of the separation layer, which allows the polar heads
of the liposomes being attached to bind strongly to the
surface. The additional empty liposomes being added help
contribute to this effect while also filling in empty gaps
between the HA and chitosan molecules. Fewer gaps in the
separation layer ensure that the layered liposomes stay intact
while the capsosome is moved around the body. Since the
capsosome will maintain its structure for a longer period with
this chemical makeup, the drugs being delivered to the body
will be released for a longer amount of time [3].
The Structure and Chemistry of Liposomes
The structure of liposomes resembles that of a basic
biological cell. They consist of a semipermeable lipid bilayer
membrane surrounding a small amount of drug molecules.
The outer membrane is called a lipid bilayer because it is
made up of two layers of lipid molecules. Lipid molecules are
characterized as having two “ends”; a hydrophilic, polar head
and a hydrophobic, nonpolar tail. In a liposome, the
hydrophobic tails of two lipid molecules move towards each
other, forming a membrane that has hydrophilic heads on both
the outside and the inside and hydrophobic tails in between
them. The membrane is semipermeable because only certain
compounds can pass through it. This is ideal for the function
of a capsosome because the drug is protectively contained but
what needs to exit the cell can leave.
The structure of liposomes is conducive to drug delivery
because it allows the drug molecules to stay intact inside the
membrane until the entire liposome is broken down by the
digestive system, ensuring that the drug stays inside long
FIGURE 1 [2]
Procedure for constructing a capsosome
It might be difficult to understand the composition of a
capsosome from just a description, but it makes more sense
once observed in a diagram. The procedure stages for
constructing a capsosome is well illustrated in figure 1, from
an American Chemical Society article about capsosome
research done in the Centre for Nanoscience and
Nanotechnology at the University of Melbourne led by Rona
Chandrawati [2]. The diagram displays the various steps that
are involved in the creation of a capsosome, including the
placement of a precursor layer, the placement of the
alternating liposome and separation layers, the addition of the
capping layer, and removal of the silica grain center. The
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Stephanie Thornton
Michael Zimlinghaus
enough to be safely delivered into the bloodstream of the
patient. Thus, having many liposomes contained within one
structure will allow even more medicine to be delivered into
the body, which is exactly what the scientists working with
capsosomes are aiming for [1].
While taking too much or too little of an over the counter drug
such as Zyrtec may not be of great consequence, patients
ingesting drugs for diseases that require very specific dosages
are at a greater risk of not receiving the correct amount of the
drug.
Protein-based medications are very susceptible to not
reaching the bloodstream of the patient intact, resulting in
improper dosage. A variety of factors can cause a discrepancy
between the amount of drug ingested by the patient and the
amount that effectively reaches the target area of the body.
According to research on protein-based drug efficiency being
conducted at the University of Melbourne, two of the most
prominent factors are unintended digestion of the proteins in
the stomach and incidental binding of the proteins to nontarget receptor sites in the bloodstream of the patient [4].
Both issues can be overcome if capsosomes are used
instead of powders or pills. Since the drugs are contained
within sturdy liposome compartments that are in turn
anchored to the overall capsosome structure, the stomach
cannot digest them as easily as traditional medications. Even
if a protein-based drug were to make it through the stomach,
there is still a risk that the protein or enzyme being delivered
might accidentally bind to a receptor site on a cell that it is not
supposed to, negating any effects the drug was intended to
have. While capsosomes do not completely remove the risk
of either of these two situations occurring, they do
significantly reduce them. As efficiency is always a key factor
when discussing drug-delivery systems, this makes
capsosomes an important development in the field of
medicine.
Current Difficulties with Capsosome Construction
Capsosomes are intricate microstructures that are the
result of long, complicated, and tedious construction
processes. Because of this, there are still a few outstanding
problems that arise when they are being built. While these
issues are not completely detrimental to the construction
processes, they will need to be solved before capsosome
production can reach an industrial-scale level of efficiency.
When working on a scale as small as individual
capsosomes, it is relatively common for the materials being
introduced during construction to incidentally bond in
unintended ways. For example, liposome clumping during
production is a prevalent issue for researchers working with
capsosomes. If even a small number of liposomes begin to
clump during the LbL construction, the entire capsosome
sample will be rendered unusable. Thus, researchers must
take great care to follow the construction process very closely.
The result of problems like liposome clumping is that
capsosome sample production takes a long time to do
correctly, especially for the level of purity that is required for
precise research. Even if many highly-trained people were put
to work constructing capsosome samples for industrial use in
the same manner as current researchers, production would be
incredibly inefficient and not economically viable at all.
While researchers working with capsosomes can take
time to carefully build capsosomes, the industrial-scale
processes that will eventually be used to make capsosomes
will be much more heavy-handed and time-constrained, while
at the same time requiring more purity and fewer errors in the
product. One of the largest challenges facing the
industrialization of capsosome production today is how to
marry the careful construction procedures that are currently in
use with the increased economic viability and efficiency that
come from the use of macro-scale industrial processes.
Long-term Release Mechanism
Capsosomes may provide a solution to this problem for
patients that must take large, regular doses of medications.
Instead of being absorbed into the body like a normal pillform drug, capsosomes are used up far less quickly. The
human body takes a longer time to decompose capsosomes
because of their highly intricate structure discussed above.
Thus, an equivalent dose of a capsosome-enclosed drug will
last longer than the same dosage given in pill form. The main
factor that determines this difference is the fact that
capsosomes must be dismantled liposome-by-liposome
within the body. In addition, each individual liposome must
be broken down, all of which requires more time and energy,
increasing the longevity of the drug. In contrast, traditional
pill-form drugs can be absorbed very quickly into the
bloodstream because the raw chemicals are already separated
from any restrictive structures.
Thus, capsosomes that contain a higher number of
liposomes will be more effective drug-delivery agents. Even
though capsosome research is still relatively new, great strides
have been made in increasing the efficiency with which
liposomes are adsorbed onto each layer. Specifically,
researchers at the University of Melbourne have been able to
achieve 95% liposome adsorption efficiency. This means that,
INNOVATION IN PROTEIN-BASED DRUG
DELIVERY SYSTEMS
The most common way of delivering protein-based
medications into the body is by producing a powder-like form
of the drug and molding into a pill, which is then taken in
orally by the patient. While this is by far the dominant
medicine delivery system in use today, it is not without its
flaws. Taking in doses of medication in pill form requires that
the pills be properly dosed to keep the level of the drug in the
body optimized. Therefore, the patient must take pills
multiple times per day to experience proper symptom relief,
while being careful not to take too much and risk overdosing.
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Michael Zimlinghaus
on average, 95% of the total space available for liposomes on
each layer of capsosomes ends up being occupied by them.
The researchers achieved this by utilizing cholesterolmodified PLL (PLLc) as an adsorption agent on the separation
layers of the capsosomes. However, this efficiency level only
lasted until the sixth layer of liposomes were deposited onto
the capsosome. After this step, the researchers say, liposomes
simply clump together without properly adsorbing onto the
forming capsosome. This limit may still be overcome in the
future if different compounds are used as adsorbing agents in
the separation layers of capsosomes, but for the present it
seems that this method will yield the most liposome-dense
capsosome structures [2].
A team of researchers at the University of Melbourne
led by James Maina published a study discussing the
efficiency and release time of protein-based drugs delivered
into the human body through capsosomes. The researchers
found that capsosome usage greatly extends the period over
which the protein-based drugs are released. They specifically
compared the release percentage over 80 days of three
different materials used to construct the liposomes [4].
combination had the highest overall drug release over the trial
period, while the DPPC and DMPC/DPPC/DOPS
combinations were both similar to each other, but
significantly less than the DMPC/DPPC. One can see that all
three of these compounds exhibited very high drug release
activity over the first ten days, levelling off but still releasing
significant amounts of the test drug over the remainder of the
eighty days. These results are very promising for the future of
capsosomes as a long-term drug delivery agent, showing that
a relatively small amount of capsosome material can be used
to give a large and long lasting dose of medication. For
comparison, traditional drug-delivery methods will usually
result in approximately 100% decomposition within ten days.
From this, it is clear to see that capsosomes greatly extend the
amount of time that a drug remains active in the patient’s body
[2].
PHENYLKETONURIA: A METABOLIC
DISORDER
PKU is a rare, hereditary metabolic disorder
characterized by the patient’s inability to digest the amino
acid phenylalanine (PHE). This amino acid is present in
nearly every food that contains protein, which makes it
difficult to avoid. PKU is specifically caused by the absence
of the gene encoding for phenylalanine hydroxylase (PAH),
the enzyme that breaks down PHE in the body [5]. PAH
typically converts PHE into the amino acid tyrosine in the
presence of tetrahydrobiopterin (BH4), which is a natural
substance found in the body. Fortunately, effective treatments
have been developed for PKU that involve the patient
ingesting artificial PAH and BH4, so PKU patients can live
normal lives if they do their best to avoid high-protein foods
and takes the appropriate dosages of medication.
Specialized Diet
The diet of a person with PKU includes restriction of
many foods since PHE is so common. This limits the types of
foods that can be safely eaten by people with PKU primarily
to vegetables and fruits, starches such as potatoes, and
mushrooms. The Eunice Kennedy Shriver National Institute
of Child Health and Human Development (NICHD) lists that
dairy products, meat, fish, chicken, eggs, and most beans and
nuts should all be avoided by PKU patients as they may cause
an unsafe spike of phenylalanine in their blood [6]. The
sweetener aspartame found in many foods, drinks,
medications, and vitamins needs to be avoided because it
releases phenylalanine when digested. Following a specific
diet can allow a person with PKU to live with less risk, but
with this extensive list of restrictions, it can obviously be very
challenging to deal with and they need additional treatment to
stay healthy. PKU formula has been developed to provide the
essential nutrients that people with PKU are not getting from
their restricted diet. A newborn receives special infant
FIGURE 2 [4]
Cumulative liposome release percentage of three
different liposome compound types
The compounds used to make the materials are all
derivatives of chemically similar lipid molecules, whose
IUPAC names are as follows; 1,2-dimyristoyl-sn-glycero-3phosphocholine (DMPC), 1,2-dipalmitoyl-sn-glycero-3phosphocholine (DPPC), and 1,2-dioleoyl-sn-glycero-3phospho-L-serine (DOPS). The three compounds tested by
the researchers were a combination of DMPC and DPPC,
DPPC alone, and a combination of DMPC, DPPC, and DOPS
[4]. The graph in figure 2 compares the cumulative liposome
release percentage of three different liposome compound
types over the course of eighty days [4]. The DMPC/DPPC
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Stephanie Thornton
Michael Zimlinghaus
formula which can be mixed with breast milk or normal
formula milk so that the child does not have too little or too
much phenylalanine [6]. Older children and adults take a
different formula which needs to be consumed every day.
Additionally, health care professionals can recommend other
supplements because each person with PKU can consume
different amounts of phenylalanine.
Symptoms and Statistics
According to the HONCode certified Genetics Home
Reference on the US National Library of Medicine website, if
PKU is not properly identified and treated soon after a child
is
born,
they
can
develop
symptoms
of
hyperphenylalaninemia (H-PHE). These symptoms include
jerky movement, seizures, developmental delays, behavioral
problem, psychiatric disorders, and permanent intellectual
disability [5]. Children born with PKU may appear normal at
birth, but symptoms can appear after about three to six
months. Untreated individuals could potentially be identified
by having lighter skin and hair than unaffected family
members and a strong ammonia-like body odor due to excess
phenylalanine in the body [5]. Statistics provided by the NIH
state that in the US, PKU occurs in 1 in 10,000 to 15,000
infants and most cases are detected during newborn screening
tests [5]. This means treatment can be started immediately and
the severe signs never show. Unfortunately, many countries
without proper medical facilities are not able to properly
identify PKU, and children who are afflicted with this disease
are not able to receive proper treatment because of this. Even
if PKU is identified, some families are not wealthy enough to
afford the expensive treatments. Therefore, it is necessary for
affordable treatments to be developed and improved.
FIGURE 3 [7]
PHE levels in person without PKU, person with PKU,
and person with PKU being treated with KUVAN
Figure 3 illustrates how the added KUVAN stimulates
the PAH enzyme to work and process the PHE in the way it
would process in a person without PKU. It also shows how a
person with PKU that has not received treatment has the
defective PAH enzyme which will not change. The image
compares the process of breaking down PHE in a person
without PKU, a person with PKU and no medication, and a
person with PKU taking KUVAN to illustrate how the
difference in PHE levels occurs. KUVAN can certainly help
keep PHE levels low, but the NICHD describes how it is not
a perfect solution to the problem because having too little
BH4 is only one reason a person may not break down
phenylalanine [6]. Therefore, it only helps some people and
must be prescribed in addition to the typical PKU diet.
Additionally, the FDA suggested that research continue for
the KUVAN medication because long-term safety and
effectiveness is still unknown. From this, it can be concluded
that other treatment options still need to be developed.
A lot of research has been conducted into discovering
new treatments for PKU, such as a regularly injected dose of
PAH or gene therapy to train the patient’s body to make PAH
on its own. However, the journal from Advanced Functional
Materials states how “gene therapy has only been employed
with limited success due to poor efficiency of gene delivery
into the liver and lack of sustained gene expression” [8]. Other
potential treatments being researched and explored by
scientists listed on the NICHD website include “large neutral
amino acid supplementation”, which could help impede
phenylalanine from entering and impairing the brain, and
“enzyme replacement therapy,” which uses a substance that is
TRADITIONAL PHENYLKETONURIA
TREATMENTS
As identified above, PKU is a rare disorder and requires large,
regular doses of PAH. Because of this, treatment for this
disorder can be expensive, and is often difficult for lowerincome families to afford. The first prescription medication
for PKU approved by the US Food and Drug Administration
(FDA) is the drug sapropterin dihydrochloride, called
KUVAN, which is in the form of tablets or powder for oral
solution. According to the official KUVAN website, the
active ingredient is a pharmaceutical version of BH4, so
taking KUVAN adds more BH4 to the body and stimulates
the PAH enzyme to process PHE which converts it to tyrosine
and lowers the level of PHE in the patient’s blood [7].
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Stephanie Thornton
Michael Zimlinghaus
much like PAH [6]. These treatment methods appear
promising, but even if they are developed and made to be
effective, they would still be quite expensive due to the rarity
of the disease and the large amount of resources needed to
produce these specialized medications.
EXAMINING THE BIG PICTURE: THE
FUTURE OF SUSTAINABLE CAPSOSOME
PRODUCTION
As of now, the processes used to construct the
liposomes, separation layers, and the completed capsosomes
are somewhat inefficient and hard to control. As with any
innovation, these flaws will most likely be fixed with
increased funding and research. The advantages that
capsosomes hold over traditional pill-form drug delivery for
protein-based medications will continue to grow with
additional research being conducted on compounds used to
create viable separation layers and liposomes.
While capsosome production may soon become more
efficient, it will likely still have a comparable overall cost to
traditional pill-form drugs. However, the similar costs of
production will yield different amounts of usable medication.
Capsosomes provide a more efficient and controlled dosing
mechanism than pills or powders, and thus allow for a higher
dosage of the drug to reach its desired target within the body.
This results in capsosomes being a more sustainable option
for protein-based drug delivery. Although the cost of each
dose may increase to a more due to a more complicated
construction process, each dose will last longer, decreasing
the number of doses needed in a given time frame to achieve
the same effect.
Once these production efficiency and accuracy
roadblocks are overcome, capsosomes may become the
primary drug-delivery method for all protein-based drugs due
to the metabolic and economic advantages that they hold over
traditional methods. Since capsosomes not only deliver these
drugs more intact than traditional pill-form, but also increase
the efficiency with which the body uses the drugs, the
economic benefits of using capsosomes instead of pills will
pay great dividends.
The social sustainability aspect of capsosomes is highly
favorable. If capsosomes become more commonplace as a
drug-delivery mechanism, additional research positions will
be created to study and improve production techniques and
the chemical aspects of the construction process. Patients that
require treatment through protein-based medications, which
comprise a large portion of all people receiving medical
treatment, will also benefit from capsosomes due to the
increase in treatment quality that they will get.
Patients that could potentially take capsosome-form
drugs will benefit from further research because the price of
drugs will decrease. Oftentimes, metabolic diseases like PKU
require expensive and frequent doses of medication. A
regimen such as this can put great financial strain on a family.
If capsosome production becomes more economically viable,
the overall cost of treatment for patients will decrease. Not
only will this save money for people already receiving
protein-based drugs, but it will also make treatment options
available for patients in countries where widespread access to
expensive pharmaceuticals is currently very restricted.
CAPSOSOMES AS A TREATMENT
MECHANISM FOR PKU
Since other treatments are only proving to be mildly
successful and PKU is causing a daily struggle in the lives of
many people, it is necessary to investigate new drug delivery
methods using innovative technology like capsosomes. A
study conducted by researchers at the Aarhus University led
by Leticia Hosta-Rigau and Brigitte Städler tested
capsosomes loaded with phenylalanine ammonia lyase (PAL)
to consider it as a potential method to treat PKU [8]. The goal
was to test replacing the defective PAH enzyme with the PAL
enzyme and protecting it from degrading too quickly in the
digestive tract or bloodstream. The problem with many drug
delivery methods with typical pills is that they degrade in the
bloodstream before they reach the intended site of action and
then they do not stay active for a long enough period.
Additionally, enzymes taken orally in a regular pill or powder
could be inactivated due to the harsh environment or the
gastrointestinal (GI) tract.
To treat PKU via capsosomes overcomes some early
degrading issues because the advanced encapsulation
structure of capsosomes protects the enzyme from unintended
folding or denaturation. The PAL enzyme was selected by the
researchers because the optimal pH of PAL is between 8.0 and
8.75 which is close to the average pH of the small intestine
[8]. This enzyme is a non-human enzyme which can be
obtained from plants, some fungi, yeast, and more. It converts
PHE into the nontoxic trans-cinnamic acid (t-ca) which is then
converted to benzoic acid in the liver and secreted via urine
[8]. This means it will work to help PKU patients by lowering
PHE levels in the body.
The capsosomes are ideal because the polymeric carrier
has a strong structural integrity, the liposomal compartments
contain and protect the enzymes, and the semipermeable
polymer membrane allows for the controlled release of the
enzymes from the interior to the external environment in the
body. The capsosome acts as an extracellular microreactor
which enables the PAL enzymes to safely reach the intestine
where they will then act to remove the unwanted PHE [8]. The
research conducted demonstrated that the PAL capsosomes
successfully conducted the enzymatic reaction to convert
PHE to t-ca repeatedly in the presence of human intestinal
epithelial cells while being exposed to a simulated
environment of the intestine [8]. The results of their lab study
with a dynamic environment like the intestine means they are
one step closer to testing and possibly treating people with
PKU via capsosomes containing therapeutic enzymes.
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Stephanie Thornton
Michael Zimlinghaus
Treatment”. Advanced Functional Materials. Wiley-VCH
Verlag.
07/01/2015.
Accessed
01/24/2015.
http://onlinelibrary.wiley.com/doi/10.1002/adfm.201404180/
abstract
Spreading awareness of disease identification and proper
treatment will follow the decrease in medication price,
leading to more lives saved and financial burdens lessened
across the world.
Even though most financial gains to be had in the
pharmaceutical industry still lie in the development of new
medicinal compounds more funding should be allocated for
the study of alternate drug-delivery systems, specifically
capsosome drug delivery. Capsosomes are a critical
development in this field because they can be used to treat a
wide variety of diseases and disorders more effectively if their
production efficiency is increased. Pills will still be widely
used for quick, short term relief, but capsosomes are much
more desirable if the proteins need to be delivered in large
doses for long-term healing. They are the key to unlocking an
entirely new way of treating metabolic diseases, and their
prominence will lead to a decrease in suffering for many
people around the world.
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[1] F. Caruso. “A Microreactor with Thousands of Sub
compartments: Enzyme-Loaded Liposomes within Polymer
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ACKNOWLEDGMENTS
We would first like to sincerely thank our co-chair
student advisor, Iman Basha, for being so kind and offering
her assistance whenever we needed guidance. Additionally,
we thank our writing instructor, Janine Carlock, for helpful
comments and instruction through her analysis of our
proposal, annotated bibliography, and outline. Thank you to
Beth Bateman Newborg for providing us with the necessary
directions to complete this assignment and her positive
encouragement of everyone. Stephanie thanks her roommate,
Kait DeOre for encouraging her to be productive. She also
thanks Joshua Tarlo for keeping her company in the library
while writing it. Michael thanks his best friend, Gary Xu, for
being an inspiration to work hard. He also would like to thank
a few of his other friends for providing examples of why it is
a bad idea to procrastinate. Finally, we thank our parents for
always supporting us and providing us with this amazing
opportunity in the Swanson School of Engineering to learn
applicable engineering and writing skills.
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Stephanie Thornton
Michael Zimlinghaus
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