Summer Fellow Poster template

1
Ketorolac tromethamine and Zosteric acid for the
Prevention of Postoperative Pelvic Adhesions
Maureen Cheung, The University of Akron, Chemical
and Biomolecular Engineering Division of Surgical
Research, Summa Health System Bradford Fenton,
M.D. Ph.D. Bi-min Newby, Ph.D. Michelle
Evancho-Chapman, B.S
P 15
Abstract
Results or Accomplishments
Introduction Following pelvic and abdominal
surgeries, postoperative adhesions are
unavoidable, occurring in 90 of major abdominal
surgery patients and in 55-100 of women
following pelvic surgery 1,2. A reliable
method to decrease pelvic adhesions would be a
useful addition to current surgical practice
preventing the need for subsequent surgeries to
break the adhesions and preventing some
postoperative complications created by adhesions
such as, small bowel obstructions, pain, and
infertility 1,2. There are two clinically
approved industry standard adhesion barriers.
However, there efficacy and utility in
laparoscopic surgery is limited because they are
both difficult to work with. Purpose Our long
term goal is to create a polymeric microsphere
encapsulated drug that can be easily applied in
both open and laparoscopic surgeries to decrease
the occurrence, severity, and development of
adhesions. The polymeric system offers the
opportunity to deliver drugs to promote healing,
prevent infection, and manage pain. The
preliminary research will focus on the synthesis,
characterization, and encapsulation of a
non-toxic anti-fouling agent, zosteric acid. The
analgesic and anti-inflammatory properties of
ketorolac tromethamine, a cox-2 inhibitor, will
also be explored. Among the reasons for
utilizing ketorolac tromethamine are its
hydrophilic nature which is similar to the
hydrophilicity of zosteric acid. Other potential
candidates for encapsulation and successful
adhesion prevention include statins, ibuprofen,
and other NSAIDs. Objectives 1) Zosteric acid
will be organically synthesized 3. This method
will be refined to ensure consistency and
purity. 2) Successfully encapsulate ketorolac
tromethamine into PLGA microspheres. We will use
a previously established and successful method of
encapsulation 4. 3) Successfully encapsulate
zosteric acid into PLGA microspheres. 4) The
microspheres will be characterized using scanning
electron microscope, laser light scattering to
determine size and size distribution, and drug
release rates will be determined at 37C.
Additionally, the yield, encapsulation efficiency
and total loading will be determined. Result
Zosteric acid was successfully synthesized with
consistency and the qualitative purity verified
by mass spectrometry. A quantitative purity will
be determined by nuclear magnetic resonance
spectroscopy. Ketorolac tromethamine was
successfully encapsulated into PLGA microspheres
and the yield, encapsulation efficency, and total
loading were determined. Zosteric acid
microspheres were synthesized but
characterization is pending. Discussion The
successful encapsulation of ketorolac
tromethamine and the successful synthesis of
zosteric acid are important steps in the
development of a potential pharmaceutical agent
for adhesion prevention. As is obvious from the
results there is still much bench-work that
must be done prior to in-vitro and in-vivo
testing and this will be the focus of the
remainder of the summer. Future Research
Following characterization, tissue culturing will
be used to determine whether it is worth pursuing
in vivo studies. We will utilize fibroblasts as
our culture cell because studies have shown that
adhesion cells are very similar to fibroblasts in
both growth and connection 1. If tissue
culturing does not provide evidence of cell
growth inhibition, than we will return to
encapsulation step utilizing another drug with
the appropriate properties. If tissue culturing
provides evidence of cell growth inhibition and
the absence of cytotoxicity, than we will pursue
animal testing. With the approval of IACUC, we
will use the model developed by Summa Health
Systems to determine the efficacy of the
microspheres in preventing adhesions.
Figure 1. Calibration curve for ketorolac
tromethamine (KT) in phosphate buffered saline
(PBS) at a wavelength of 323.
Figure 2. Representative graphical representation
of UV/VIS spectroscopy of a PLGA microsphere
encapsulating KT.
Figure 3. Yield of KT microspheres.
Figure 4. Loading Efficiency of KT microspheres.
Materials and Methods
Zosteric Acid Synthesis Microsphere
Encapsulation
Figure 5. Mass spectrometry results for a
representative batch of ZA. Left Negative ion
polarity. Right Positive ion polarity.
Discussion
From Figure 5, it is concluded that ZA was
successfully synthesized. Since only a
qualitative purity and consistency has been
established through mass spectrometry, a
quantitative assessment is needed utilizing
nuclear magnetic resonance spectroscopy. At this
time, ZA microspheres have been made but
assessment is pending. Ketorolac tromethamine
was successfully encapsulated into PLGA
microspheres and the yield, encapsulation
efficency, and total loading were determined.
The yields and encapsulation efficiency are
consistent with those expected for a hydrophilic
agent such as KT. The successful encapsulation
of ketorolac tromethamine and the successful
synthesis of zosteric acid are important steps in
the development of a potential pharmaceutical
agent for adhesion prevention. As is obvious
from the results there is still much bench-work
that must be done prior to in-vitro and in-vivo
testing and this will be the focus of the
remainder of the summer.
p-coumaric acid (pCA)
Chlorosulfonic Acid (CSA)
Zosteric Acid (ZA)

1. Dissolve drug in dH2O. Dissolve PLGA in DCM
2. Add aqeuous drug to PLGA solution. Emulsify.
3. Add emulsified solution to external aqueous phase
   (PVP or PVA).
4. Allow solvent to evaporate at 1 atm with
   stirring.
5. Centrifuge and wash.
6. Lyphilize.

References
1 Liakakos T, Thomakos N, Fine PM, Dervenis C,
Young RL. Peritoneal adhesions etiology,
pathophysiology, and clinical significance.
Recent advances in prevention and management. Dig
Surg. 200118(4)260-73. 2 El-Mowafi D,
Diamon, M. Are Pelvic Adhesions Preventable?
Surgical Technology International 200311
222-235. 3 Alexandratos, Spiro D. Synthesis and
purification of zosteric acid. The University of
Tennessee Research Corporation, assignee. Patent
5990336. 23 Nov. 1999. Print. 4 Jain, RA. The
manufacturing techniques of various drug loaded
biodegradable poly(lactide-co-glycolide) (PLGA)
devices. Biomaterials, 2000. 21(23)2475-90.