Content uploaded by A. Shukri Mustapa Kamal
Author content
All content in this area was uploaded by A. Shukri Mustapa Kamal on Jan 06, 2021
Content may be subject to copyright.
JOURNAL OF CRITICAL REVIEWS
ISSN- 2394-5125 VOL 7, ISSUE 16, 2020
862
FABRICATION AND DOSIMETRIC
CHARACTERIZATION OF NOVEL BIO-BASED
TISSUE SUBSTITUTE PHANTOM MATERIALS
Damilola Oluwafemi Samson1, Ahmad Shukri 2, Mohd Zubir Mat Jafri 3, Rokiah Hashim 4, Mohd Zahri
Abdul Aziz 5, Mohd Fahmi Mohd Yusof 6
1 School of Physics, Universiti Sains Malaysia, Gelugor, Penang, 11800, Malaysia
1,4 School of Industrial Technology, Universiti Sains Malaysia, Gelugor, Penang, 11800, Malaysia
1 ,5Advanced Medical and Dental Institute, Universiti Sains Malaysia, Bertam, Penang, 13200, Malaysia
6 School of Health Sciences, Universiti Sains Malaysia, Kota Bharu, Kelantan, 16150, Malaysia
Corresponding author Email: saamdoftt82@gmail.com
Received: 16 March 2020 Revised and Accepted: 19 June 2020
ABSTRACT: We developed soy protein concentrate–soy protein isolate bonded Rhizophora spp. particleboard
phantoms using sodium hydroxide and a bio-based curing agent (itaconic acid polyamidoamine-epichlorohydrin
resin). The probability of photon interactions was obtained at selected energies using Monte Carlo simulation
with EGSnrc PEGS4 and used to interpolate experimental results, and compared with that of water and solid
water phantoms. The dosimetric parameters were estimated through the use of an ionization chamber and
Gafchromic EBT3 film dosimeters to ensure the equivalence of these phantoms. The particleboard phantoms
were found to have the better agreement of average densities and effective atomic number of all samples
compared to that of water. The evaluated relative difference in the depth-of-dose maximum () was 2.90%,
2.96%, 2.87% and 2.93% for 6 MV photons, while those of 10 MV photons were 8.84%, 10.03%, 8.06% and
9.81%, respectively. The percentage depth dose curves of the electron beams revealed an enhanced surface dose.
The comparison between the measured dosimetric parameters using Gafchromic EBT3 films at all depths
indicates good consistency with a difference of within 2% and 9% for 6 MV and 10 MV photon beams. In
addition, similar results were found for electron beams with discrepancies within 2% and 5.5% for 6 MeV and
15 MeV, respectively. The fabricated particleboard phantoms were shown to be ideal for use in radiation
therapy dosimetry as tissue substitute phantom material.
KEYWORDS: Bio-based adhesives, Tissue substitute, Rhizophora spp., dosimetric parameters, EGSnrc
1. INTRODUCTION
Modern methods of treatment in clinical radiation therapy, such as intensity-modulated radiation therapy
(IMRT), stereotactic body radiation therapy (SBRT), and image-guided radiation therapy (IGRT), tackle
specific dose distributions and require accurate dose estimations (Jang et al., 2009; Mostaar et al., 2011). The
precise measurement of the resultant dose distribution is the main objective in clinical radiation therapy
dosimetry (Rashidi et al., 2020). It has been shown that the correct estimation of the dose distribution can be
obtained with suitable dosimeters to validate the treatment plan of a high-dose gradient conformal treatment.
Amongst the available varieties of dosimetric tools, ionization chambers (ICs) and radiochromic films remain
the convenient choice for determining the dose distribution in these modern methods of radiation therapy (Borca
et al., 2013; Massillon-JL et al., 2012). ICs are commonly used because of their unique features such as high-
precision, stability, dose rate independence, excellent linearity, and little to no fading. Additionally, for a wide
variety of radiation energies, ICs are considered equivalent to soft tissue. On the other hand, radiochromic films
are essentially energy independent, with high spatial resolution, and provides verification in a two-dimensional
plane (Borca et al., 2013). They are ideal for particleboard phantom dosimetry as well as any other dosimetric
use in radiation therapy because of their near tissue- and water-equivalent characteristics (Butson et al., 2010).
Water is one of the significant reference phantom materials used in medical radiation centers for quality
assurance (QA) because of its particular radiation attenuation characteristics (Dewerd & Kissick, 2014).
Nevertheless, due to its liquidity and the fact that some radiation dosimetric tools are not suitable for use in
water, its use is not always practical (Khan, 2010). It has been one of the more challenging endeavours in the
field of tissue simulation to precisely mimic water for photons and electrons over a wide range of energies using
a specific solid material. When water is utilized, the water container is vulnerable to mechanical instability and
if it is of a sealed form, there can be a problem of maintaining the purity of the water. A novel tissue substitute
material is therefore needed that can provide appropriate and accurate simulations and be made water-equivalent
JOURNAL OF CRITICAL REVIEWS
ISSN- 2394-5125 VOL 7, ISSUE 16, 2020
863
for dose determinations in photon and electron applications. Mangrove Rhizophora spp. (R. spp.) wood has been
found to display correlations in dosimetric characteristics with water due to its tissue-equivalent nature, effective
atomic number, and percentage depth dose (Ababneh et al., 2016; Banjade et al., 2001).
2. LITERATURE REVIEW
Tissue substitute phantom materials are effective tools for radiation therapy technique development,
optimization, and performance evaluation (Khan, 2010). Since the proposition of the appropriateness of
Rhizophora spp. (R. spp.) wood as a potential phantom material, several authors have researched and shown that
R. spp. is a highly attractive material for use as an effective tissue substitute for a variety of uses, including high
energy photon and electron radiation therapy, as well as X-ray imaging (Abuarra et al., 2014; Banjade et al.,
2001; Tousi et al., 2014). In addition, typical R. spp. wood has high carbon content followed by oxygen,
hydrogen, and other common elements similar to the elemental composition of human tissue making it
appropriate for use as phantom material. Untreated R. spp. wood, however, has some disadvantages in its use as
phantom material because of concerns like density non-uniformity, inflexibility, treatment surface abnormality,
and so on (Ababneh et al., 2016). Alternatively, previous studies have suggested the appropriateness of bio-
based adhesives such as soy proteins, tannins, starch, lignin, animal glue, natural rubber, etc. with specific
characteristics in the manufacture of R. spp. particleboards (Ababneh et al., 2016; Abuarra et al., 2014). The
main stimulus for the renewed interest in bio-based adhesives was the raised concerns from the general public
towards environmental safety when formaldehyde is used as an adhesive (Koshy et al., 2015). In fact, soy
protein-based adhesives have already been widely regarded as an alternative bio-based wood adhesive in
industrial applications (Chien & Shah, 2012; Gui et al., 2013; Zhang et al., 2017).
Soy proteins include defatted soy flour (DSF), soy protein concentrate (SPC), and soy protein isolate
(SPI). Twenty different monomers of amino acids, such as hydroxyl (–OH), sulphite (–SH), carboxylic (–
COOH), and amino groups (–NH2) connected through peptide bonds, form the primary structure of complex soy
protein macromolecules and dominate their properties. In addition, soy protein can be divided into four fractions
which are categorized according to their sedimentation properties i.e. 2S, 7S, 11S, and 15S fractions (letter S
denote Svedberg units) and comprise of 8%, 35%, 52%, and 5% of the total protein content, respectively (Wang,
2006). These monomers are bound by many side chains and interact with several inorganic and organic
materials, and cellulosic fibers. Soy proteins are highly oxygenated carbon compounds and this makes them
ideal for use in the manufacture of phantom materials equivalent to tissue and water, and can be used either as
adhesive with curing (addition of cross-linking agents) or without curing (Gui et al., 2013; Zhang et al., 2017).
Yet due to its susceptibility to changes in temperature, pH, viscosity, ionic strength, and pressing conditions, an
unmodified soy protein has been identified as a weak adhesive (Frihart & Satori, 2013). Its poor mechanical and
dimensional stability characteristics also introduce added disadvantages. However, to break the internal bonds
and disperse the polar protein molecules a chemical change is necessary (Gui et al., 2013; Kumar et al., 2002;
Zhang et al., 2017). This cross-linking reaction can be effected either by co-polymerizing functional groups in
unfurled soy protein alone or with convenient cross-linking agents to form water-durable or insoluble dried
adhesives (Chien & Shah, 2012; Kumar et al., 2002).
Polyamidoamine-epichlorohydrin (PAE) adhesive, commonly known as Kymene 557H, has been
studied as a cross-linker for soy proteins. Itaconic acid polyamidoamine-epichlorohydrin (IA-PAE) resins are
highly regarded due to their incomparable multifunctionality, enhanced mechanical characteristics, stable water
resistance, and good wood-bonding ability (Gui et al., 2013; Zhang et al., 2017). This work thus centered on the
fabrication of novel tissue substitute phantom materials from soy protein concentrate (SPC), soy protein isolate
(SPI), sodium hydroxide (NaOH) (10 wt%), a bio-based curing agent (itaconic acid polyamidoamine-
epichlorohydrin resin) (15 wt% IA-PAE), and mangrove R. spp. wood particles. The dosimetric properties were
evaluated on an Elekta Synergy linear accelerator (LINAC) with dual photon energies of 6 MV and 10 MV and
6 MeV and 15 MeV electron beams. The beams were simulated based on International Atomic Energy Agency
(IAEA) TRS-398 codes of practice (Mather & Mansi, 2008) with a reference field size of 10 x 10 cm2, source-
to-surface distance (SSD) of 100 cm, and a dose of 100 cGy. These measurements were performed using an
ionization chamber (NE 2581/334, 0.6 cm3) and Gafchromic EBT3 film dosimeters.
3. METHODOLOGY
3.1 Bio-based Adhesive Preparation and Manufacture of Particleboard Phantoms
The present work involves two types of bio-based tissue substitute phantom samples (SPC/NaOH/IA-
PAE/R. spp. and SPI/NaOH/IA-PAE/R. spp.). In the first case, 30 g of SPC was dissolved into 70 g of distilled
water, followed by the addition of 15 wt% IA-PAE that was already synthesized with a viscosity of 100.4 0.3
mPa.s, pH of 6.7, and solid content of 55.9 0.01 wt%. The mixture was stirred slowly for 30 minutes, then
held at pH 11.0 with 2M of NaOH. In the second case, 12 g of SPI was dispersed into distilled water (88 g) and
stirred for 30 minutes, then 15 wt% IA-PAE was applied dropwise and the solution alkalized to pH 11.0.
JOURNAL OF CRITICAL REVIEWS
ISSN- 2394-5125 VOL 7, ISSUE 16, 2020
864
The moisture content of the air-dried R. spp. wood particles were retained within 5–8%, due to the fact
that higher moisture content would cause accumulation of water that could lead to blistering and swelling on the
particleboards. The sample mixture in each case was then evenly mixed with R. spp. wood particles ( 74 μm)
using a rotary mixer machine (Universal Grinding Mill DFY, 1000, China) for 30 minutes at 25 krpm to
preserve good homogeneity and uniformly distributed in a mould. The SPC-SPI/NaOH/IA-PAE/R. spp.
mixtures were pre-pressed at 0.49 MPa for 5 minutes at room temperature to decrease the air cavity inside the
sample mixture. A total of 30 particleboard phantoms of dimensions 30 x 30 x 1 cm3 were developed at 20 MPa
and 170 for 20 minutes using a hydraulic hot press machine and the target density for the SPC-SPI was set at
1.0 gcm-3 in accordance with widely used solid water phantoms. Before processing, the particleboard phantom
samples were kept under ambient conditions at room temperature and relative humidity of 55% for two weeks.
3.2 Theoretical Calculation of Average Density and Effective Atomic Number
Optimal particleboard phantom materials should ideally have radiological properties, as well as density
(i.e., the density of the particleboard material can be set to 1.0 gcm-3 in the TPS) and effective atomic number
equivalent to tissue or water (AAPM-21, 1983). The average particleboard densities () were determined using
the gravimetric technique given by the following expression in Eq. (1):
To calculate the uncertainties in the experimental densities () of the particleboards, we compared the
propagation of uncertainty relation based on the external dimensions given by Eq. (2):
where, and denotes the respective mass, length, width, and thickness of the particleboards, ,
and are the errors in, and , respectively.
Tissue substitute phantom materials are made of various elements with variable proportions to create a single
entity. This composition of all elements describes a composite material or compound and results in an effective
atomic number () (Khan, 2010). The values of the bio-based particleboards were evaluated based on the
chemical analysis using energy dispersive X-ray analysis (EDXA) (Turşucu et al., 2013):
where, , , and denotes the atomic numbers, effective atomic weight and fractional weight of the jth
element in the molecule.
3.3 Dosimetric Evaluation of Particleboard Phantoms
3.3.1 Probability of Photon Interactions
The interaction of a photon beam with matter results in photon energy degradation and a spatial pattern
of the energy deposition points. Monte Carlo simulation with EGSnrc PEGS4 (EGSnrc – electron gamma
shower by National Research Council, PEGS4 – pre-electron gamma shower 4) was applied to study the
histories of photon interactions in the particleboards. This is because EGSnrc PEGS4 is well-suited for
modelling physical interactions in clinical external beam radiation therapy (EBRT), such as Compton scattering
with outer and inner-shell electrons, Bremsstrahlung, photoelectric effect, electron-positron pair production, and
annihilation. PEGS4 is a code containing the basic elements and data of the particles and their physical
properties including density, effective atomic number, and electron density of the medium (Kawrakow, 2013).
We considered in the code the four most significant mechanisms of photon interaction in radiation therapy:
photoelectric effect, Rayleigh scattering, Compton scattering, and pair production. The elemental composition
information of both the constructed particleboards was used to achieve the probability of photon interactions in
the selected energies and the interpolated experimental results were compared with those of water and solid
water phantoms.
3.3.2 Determination of Percentage Depth Dose (PDD) using Ionization Chambers (ICs)
Phantom samples of thickness 15 cm were arranged on the LINAC couch to provide backscatter to the
photon and electron beams. A Markus plane-parallel IC (NE 2581/334, 0.6 cm3) was attached to an electrometer
and positioned in the chamber slot in the particleboard. The IC was then located at an SSD of 100 cm and the
JOURNAL OF CRITICAL REVIEWS
ISSN- 2394-5125 VOL 7, ISSUE 16, 2020
865
field size set to 10 x 10 cm2 on the surface in accordance with the calibration parameters in the dosimetry
protocol of IAEA TRS-398 (Mather & Mansi, 2008). Exposures were carried out using photon beams of 6 MV
and 10 MV, and electron beams of 6 MeV and 15 MeV with 100 monitor units (MU). Particleboard slabs were
added above the IC to ascertain the ionization at depth below the surface of the phantoms, and the SSD and field
size subsequently re-adjusted. The measurements were repeated until a depth of approximately 20 cm was
reached and compared with that of water and solid water phantoms. During these measurements, both the gantry
and collimator angles were fixed at 0o and PDD determination for each depth took 6 seconds. After each
exposure, a time delay of 2 minutes was applied before adding the next slab of particleboard. This is done to
take proton production into account. One way to describe the central axis dose distribution is to normalize dose
at depth with respect to dose at a reference depth. The PDD can be characterized based on four parameters
including depth in a phantom, field size, SSD, and photon beam energy. It ranges in value from zero at depth
to 100 at . These values were computed as the quotient, calculated as a percentage of the absorbed dose
at a given depth to the absorbed dose at a specified reference depth (maximum depth) along the central
axis of the phantom samples (Feye, 2018). The PDD is therefore defined as:
The electrons generated from the air contribute more to the dose at extended distances near the surface than at
normal SSDs (Podgorsak, 2006). The discrepancy in the calculated PDD of fabricated SPC-SPI particleboards,
water, and solid water phantoms was expressed as a percentage given by Eq. (5):
where, is the PDD for the manufactured SPC-SPI particleboard phantom samples and
is the PDD for the water and solid water phantoms, respectively.
3.3.3 Percentage Depth Dose (PDD) Measurements using Gafchromic EBT3 Film
A clinical LINAC was used to assess the PDD for each sample of SPC-SPI/NaOH/IA-PAE R. spp.
particleboards and the dose at each measurement location was computed using the IAEA TRS-398 protocol for
photon and electron beams (Mather & Mansi, 2008). These measurements and calculations were performed
using both Gafchromic EBT3 films and a treatment planning system (TPS) for 6 MV and 10 MV photon beams
as well as 6 MeV and 15 MeV electron beams. The material density in the TPS was set to that physically
measured for each material tested. Gafchromic EBT3 films were cut and inserted along the vertical direction at
the mid-plane of the particleboard phantoms. Irradiation was made parallel to the beam for a static 10 x 10 cm2
field size at 100 cm SSD and 100 cGy dose. After irradiation, the films were scanned with an Epson 10000XL
flatbed scanner. The PDD data was then normalized to the maximum dose, expressed as a percentage, and the
percentage variation was measured as indicated in Eq. (4) and Eq. (5), respectively. The PDD curve of the
particleboard phantoms was compared with that of calculated values of water and solid water phantoms as
standard phantom materials used in the radiation therapy range.
4. Results and Findings
4.1 Elemental Analysis of Particleboard Samples
The density of a phantom material is crucial in the selection of material as a tissue substitute. The
average density and percentage deviation of the fabricated particleboard phantom samples are presented in
Table 1. Good agreement was observed in the densities of all the samples as compared to that of water (1.0 gcm-
3). As can be seen in Table 2, both particleboard phantom samples contain significant elements that were
required for the construction of a tissue substitute material. The most common elements found in the SPC-SPI
particleboard materials were C, O, N, Na, Mg, P, S, Cl, K, Ca, Mn, and Fe. The highest contents of C and O in
the particleboard matrix were assigned to the presence of lignin (C10H12O3), hemicellulose (C5H8O4), and
cellulose (C6H10O5) in the R. spp. wood (Abuarra et al., 2014). In addition, the investigated particleboard
materials have the value of effective atomic number () close to water (AAPM-21, 1983; Kurudirek, 2014)
and in good agreement to previous studies (Ababneh et al., 2016; Abuarra et al., 2014). This is likely due to the
similarity in densities and material compositions, resulting in a closely similar effective atomic number. The
tissue substitute disposition of a sample is directly related to its value (Singh et al., 2018). Due to their high
value, and the high C, and O content, the SPC and SPI particleboard samples can be evaluated with the best
tissue substitute phantom materials to be used for radiation therapy dosimetry.
JOURNAL OF CRITICAL REVIEWS
ISSN- 2394-5125 VOL 7, ISSUE 16, 2020
866
Table 1: Average Density and Percentage Deviation of Bio-based Tissue Substitute Particleboard Phantoms
Particleboard Phantoms
Average density, (gcm-3) SD
Percentage deviation, (%)
SPC/NaOH/IA-PAE/R. spp.
1.001 0.006
0.023
SPI/NaOH/IA-PAE/R. spp.
0.993 0.008
0.020
SD = standard deviation
Table 2: Elemental Weight (%) and Effective Atomic Number of Bio-based Tissue Substitute Particleboard
Phantoms
Sampl
e
Elemental Weight (%)
H
C
N
O
Na
Mg
P
S
Cl
K
Ca
Mn
Fe
Zn
A
11.1
1
-
-
88.8
9
-
-
-
-
-
-
-
-
-
-
7.42
a
B
-
49.7
3
4.8
8
44.3
5
0.2
5
0.1
0
-
-
0.2
7
0.2
5
0.1
5
-
-
0.0
2
7.49
b
C
-
54.6
9
-
44.0
8
0.3
3
0.0
3
0.0
6
0.0
7
0.3
8
0.0
5
0.2
0
0.0
5
0.0
6
-
7.56
b
D
5.25
42.1
0
0.6
5
52.0
0
-
-
-
-
-
-
-
-
-
-
7.18
c
E
6.03
41.7
2
0.2
7
51.9
8
-
-
-
-
-
-
-
-
-
-
7.15
d
Note: A = Water, B = SPC/NaOH/IA-PAE/R spp., C = SPI/NaOH/IA-PAE/R spp., D = Arabic gum/R spp., E =
Almond gum/R spp.
a (AAPM-21, 1983), b current study, c (Abuarra et al., 2014) , d (Ababneh et al., 2016).
4.2 Probability of Photon Interactions
Because tissue or water equivalent phantoms have the same basic characteristics to those of tissue with
respect to radiation interactions, they are usually used in clinical QA procedures for both diagnostic and
therapeutic applications. Figures 1(a-b) show the variations in the fractional interaction probability of photons in
SPC and SPI particleboard phantoms with incident photon energies ranging from 1 keV to 65 MeV. The first
component of interactions is simply a contribution of photon energies less than 1.022 MeV, caused by the
dominant process of Rayleigh scattering, photoelectric effect, and Compton scattering interactions. The
Rayleigh scattering does not contribute to dose and represents just a few percent of total attenuation at
kilovoltage photon energies (Attix, 1986). As the photon energy increases beyond the binding energy of the K
electron, the Compton scattering becomes a dominant process. In the high-energy region, a particular phase of
absorption begins to dominate, i.e. pair production (Attix, 1986; Khan, 2010). It is worth noting that the
particleboard samples show almost similar variations throughout based on the dominance of different photon
interaction processes in the different energy regions. From Figs. 2(a-b), it is observed that the interaction
probabilities inside the particleboard samples are close to that of water and solid water phantoms within the
energy range 6 MeV to 15 MeV. This demonstrates that SPC-SPI-based materials can be used as tissue
substitute phantoms with an impact almost similar to water, particularly with respect to Compton scattering
interactions at photon energies between 6 MeV and 15 MeV.
JOURNAL OF CRITICAL REVIEWS
ISSN- 2394-5125 VOL 7, ISSUE 16, 2020
867
Figure 1. Analysis of Fractional Probability of Photon Interaction between SPC-SPI Particleboards, Water and
Solid Water Phantoms: (a) SPC/NaOH/IA-PAE/R spp. and (b) SPI/NaOH/IA-PAE/R spp.
Figure 2. Fractional Probability of Compton Scattering Interaction of SPC-SPI Particleboards, Water and Solid
Water Phantoms: (a) SPC/NaOH/IA-PAE/R spp. and (b) SPI/NaOH/IA-PAE/R spp. for the Photon Energy
Range 6–15 MeV.
(a)
(b)
(a)
(b)
JOURNAL OF CRITICAL REVIEWS
ISSN- 2394-5125 VOL 7, ISSUE 16, 2020
868
4.3 Depth-Dose Curves for Ionization Chambers and Gafchromic EBT3 Film Dosimeters
The measured PDD values of 6 MV and 10 MV photon beams, and 6 MeV and 15 MeV electron
energies with the use of IC (NE 2581/334, 0.6 cm3) at reference field size of 10 x 10 cm2 and nominal distance
of 100 cm were plotted to obtain PDD curves for the particleboards, water, and solid water phantoms and the
results are presented in Figs. 3(a-d) and Figs. 4(a-d), respectively. The computed profiles were normalized to the
maximum dose in the depth-dose profile positioned symmetrically opposite the IC within the photon beam to
ensure the profiles being compared were equivalent to those of water and solid water phantoms. The depth-of-
dose maximum () are 1.5 cm, 2.5 cm and 3.0 cm, respectively. The percentage differences in the in
comparison to that of water and solid water phantoms were at most 2.90% and 2.96% for SPC, 2.87% and
2.93% for SPI at 6 MV, whereas for those of 10 MV are 8.84% and 10.03% for SPC, and 8.06% and 9.81% for
SPI, respectively at the dose build-up regions. Moreover, the PDD curves of the electron beams for the
particleboard phantoms showed an improved surface dose when compared with that of water and solid water
phantoms. Both SPC and SPI phantoms deliver a reasonably homogeneous dose from the surface to a specific
depth, after which the dose falls off rapidly with increasing depth, eventually to near zero values. The results
obtained for for both SPC and SPI particleboard phantoms for 6 MV and 10 MV photons, and 6 MeV and
15 MeV electrons energies were found within the limit.
Figures 5(a-d) and 6(a-d) illustrate the PDD profiles of the SPC and SPI particleboards measured from
their surfaces and compared with that of water and solid water phantom calculated PDD data for 6 MV and 10
MV photon beams, and 6 MeV and 15 MeV electron beams using Gafchromic EBT3 films. When the obtained
results were compared with that of the water and solid water phantoms, the surface doses of the particleboard
phantoms were found to be lower. The comparison between the measured dosimetric parameters at all depths
indicates good consistency with a difference of within 2% and 9% for 6 and 10 MV photon beams. With
electron beams, comparable results were found. In these case, discrepancies found were within 2% and 5.5% for
6 and 15 MeV, respectively. These results are in good agreement with the previous work on the PDD of
renewable resources in the respective photon and electron energy ranges (Banjade et al., 2001).
Figure 3. Comparison between Calculated values of Percentage Depth Dose (PDD) Curves for SPC/NaOH/IA-
PAE/R. spp. Particleboard, Water and Solid Water Phantoms by Ion Chamber with a 10 x 10 cm2 Field Size and
SSD (100 cm) determined at: (a-b) 6 MV photons and 6 MeV electrons and (c-d) 10 MV photons and 15 MeV
electrons.
6 MV
6 MeV
(a)
10 MV
15 MeV
(b)
(c)
(d)
JOURNAL OF CRITICAL REVIEWS
ISSN- 2394-5125 VOL 7, ISSUE 16, 2020
869
Figure 4. Correlation of Percentage Depth Dose (PDD) Curves for SPI/NaOH/IA-PAE/R. spp. Particleboard,
Water and Solid Water Phantoms by Ion Chamber with a 10 x 10 cm2 Field Size and SSD (100 cm) at: (a-b) 6
MV photons and 6 MeV electrons and (c-d) 10 MV photons and 15 MeV electrons.
Figure 5. Evaluated Percentage Depth Dose (PDD) Plots with the use of Gafchromic EBT3 Film for
SPC/NaOH/IA-PAE/R. spp. Particleboard, Water and Solid Water Phantoms ascertained at: (a-b) 6 MV photons
and 6 MeV electrons and (c-d) 10 MV photons and 15 MeV electrons.
6 MV
6 MeV
10 MV
15 MeV
(a)
(b)
(c)
(d)
(a)
(b)
(c)
(d)
6 MV
6 MeV
10 MV
15 MeV
JOURNAL OF CRITICAL REVIEWS
ISSN- 2394-5125 VOL 7, ISSUE 16, 2020
870
Figure 6. Comparison of Calculated Percentage Depth Dose (PDD) with the use of Gafchromic EBT3 Film for
SPI/NaOH/IA-PAE/R. spp. Particleboard, Water and Solid Water Phantoms at: (a-b) 6 MV photons and 6 MeV
electrons and (c-d) 10 MV photons and 15 MeV electrons.
5. CONCLUSION
The obtained results showed that NaOH/IA-PAE resin had effectively enhanced the SPC-SPI-R spp.
particleboards, leading to close similarities in density, material composition, and effective atomic number to that
of water, and demonstrating its tissue substitute potential. The results further showed that for 6 MeV to 15 MeV
photon energies, both SPC and SPI particleboard samples had interaction probabilities that were close to that of
water and solid water. This indicates that the bio-based particleboard phantoms present an impact almost similar
to water especially with regards to Compton scattering interactions. In addition, the results for 6 MV and
10 MV photons, and 6 MeV and 15 MeV electrons were found within the desired limits. The measured PDD
curves for both photon and electron energies show good agreement with that of water and solid water. These
findings demonstrate the appropriateness of the bio-based particleboards as potential novel tissue substitute
phantom materials for radiation therapy dosimetry.
6. ACKNOWLEDGEMENT
We acknowledge Universiti Sains Malaysia for fully funding this study under the Research University grant no.
304/PFIZIK/6316173 and Fundamental Research Grant Scheme no. 203/PTEKIND/6711525.
Conflicts of Interest: The authors have no relevant conflicts of interest to disclose.
7. REFERENCES
[1] AAPM-21. (1983). A protocol for the determination of absorbed dose from high energy photon and
electron beams: Task Group-21. Medical Physics, 10, 741–771.
[2] Ababneh, B., Tajuddin, A. A., Hashim, R., & Shuaib, I. L. (2016). Investigation of mass attenuation
coefficient of almond gum bonded Rhizophora spp. particleboard as equivalent human tissue using XRF
technique in the 16.6–25.3 keV photon energy. Australasian Physical and Engineering Sciences in
Medicine, 39(4), 871–876. https://doi.org/10.1007/s13246-016-0482-6
[3] Abuarra, A., Hashim, R., Bauk, S., Kandaiya, S., & Tousi, E. T. (2014). Fabrication and characterization of
6 MV
6 MeV
10 MV
15 MeV
(a)
(b)
(c)
(d)
JOURNAL OF CRITICAL REVIEWS
ISSN- 2394-5125 VOL 7, ISSUE 16, 2020
871
gum Arabic bonded Rhizophora spp. particleboards. Materials and Design, 60, 108–115.
https://doi.org/10.1016/j.matdes.2014.03.032
[4] Attix, F. H. (1986). Introduction to Radiological Physics and Radiation Dosimetry. WILEY-VCH Verlag
GmbH & Co. KGaA. Weinheim, 6-54.
[5] Banjade, D. P., Tajuddin, A. A., & Shukri, A. (2001). A study of Rhizophora spp wood phantom for
dosimetric purposes using high-energy photon and electron beams. Applied Radiation and Isotopes, 55(3),
297–302. https://doi.org/10.1016/S0969-8043(01)00057-4
[6] Borca, V. C., Pasquino, M., Russo, G., Grosso, P., Cante, D., Sciacero, P., Girelli, G., La Porta, M. R., &
Tofani, S. (2013). Dosimetric characterization and use of GAFCHROMIC EBT3 film for IMRT dose
verification. Journal of Applied Clinical Medical Physics, 14(2), 158–171.
https://doi.org/10.1120/jacmp.v14i2.4111
[7] Butson, M. J., Yu, P. K. N., Cheung, T., & Alnawaf, H. (2010). Energy response of the new EBT2
Radiochromic film to X-ray radiation. Radiation Measurements, 45(7), 836–839.
https://doi.org/10.1016/j.radmeas.2010.02.016
[8] Chien, K. B., & Shah, R. N. (2012). Novel soy protein scaffolds for tissue regeneration: Material
characterization and interaction with human mesenchymal stem cells. Acta Biomaterialia, 8(2), 694–703.
https://doi.org/10.1016/j.actbio.2011.09.036
[9] Dewerd, L. A., & Kissick, M. (2014). Biological and Medical Physics, Biomedical Engineering The
Phantoms of Medical and Health Physics: Devices for Research and Development.
http://www.springer.com/series/3740
[10] Feye, A. T. (2018). Percentage depth dose and beam profile measurements for electron and photon beam in
reference field size for different energies. International Journal of Scientific & Engineering Research, 9(2),
1460–1464.
[11] Frihart, C. R., & Satori, H. (2013). Soy flour dispersibility and performance as wood adhesive. Journal of
Adhesion Science and Technology, 27(18–19), 2043–2052.
https://doi.org/10.1080/01694243.2012.696948
[12] Gui, C., Wang, G., Wu, D., Zhu, J., & Liu, X. (2013). Synthesis of a bio-based polyamidoamine-
epichlorohydrin resin and its application for soy-based adhesives. International Journal of Adhesion and
Adhesives, 44, 237–242. https://doi.org/10.1016/j.ijadhadh.2013.03.011
[13] Jang, K. W., Cho, D. H., Shin, S. H., Yoo, W. J., Seo, J. K., Lee, B., Kim, S., Moon, J. H., Cho, Y. H., &
Park, B. G. (2009). Characterization of a scintillating fiber-optic dosimeter for photon beam therapy.
Optical Review, 16(3), 383–386. https://doi.org/10.1007/s10043-009-0072-x
[14] Kawrakow, I. (2013). EGSnrc: The EGSnrc Code System : Monte Carlo Simulation of Electron and
Photon Transport. Manual - Guides, 2001–2013.
[15] Khan, F. M. (2010). The physics of radiation therapy. Lippincott Williams & Wilkins, Philadelphia, USA,
1-388.
[16] Koshy, R. R., Mary, S. K., Thomas, S., & Pothan, L. A. (2015). Environment friendly green composites
based on soy protein isolate - A review. Food Hydrocolloids, 50, 174–192.
https://doi.org/10.1016/j.foodhyd.2015.04.023
[17] Kumar, R., Choudhary, V., Mishra, S., Varma, I. K., & Mattiason, B. (2002). Adhesives and plastics based
on soy protein products. Industrial Crops and Products, 16(3), 155–172. https://doi.org/10.1016/S0926-
6690(02)00007-9
[18] Kurudirek, M. (2014). Effective atomic numbers and electron densities of some human tissues and
dosimetric materials for mean energies of various radiation sources relevant to radiotherapy and medical
applications. Radiation Physics and Chemistry, 102, 139–146.
https://doi.org/10.1016/j.radphyschem.2014.04.033
[19] Massillon-JL, G., Chiu-Tsao, S.-T., Domingo-Munoz, I., & Chan, M. F. (2012). Energy Dependence of the
New Gafchromic EBT3 Film:Dose Response Curves for 50 KV, 6 and 15 MV X-Ray Beams. International
Journal of Medical Physics, Clinical Engineering and Radiation Oncology, 01(02), 60–65.
https://doi.org/10.4236/ijmpcero.2012.12008
[20] Mather, S. J., & Mansi, L. (2008). IAEA Technical Report Series. European Journal of Nuclear Medicine
and Molecular Imaging, 35(5), 1030–1031. https://doi.org/10.1007/s00259-008-0767-4
[21] Mostaar, A., Hashemi, B., Zahmatkesh, M. H., Aghamiri, S. M. R., & Mahdavi, S. R. (2011).
Development and characterization of a novel PRESAGE formulation for radiotherapy applications.
Applied Radiation and Isotopes, 69(10), 1540–1545. https://doi.org/10.1016/j.apradiso.2011.06.014
[22] Podgorsak, E. B. (2006). External Photon Beams: Physical Aspects’. Radiation Oncology Physics: A
Handbook for Teachers and Students. In IAEA. https://doi.org/10.1021/jf030837o
[23] Rashidi, A., Abtahi, S. M. M., Saeedzadeh, E., & Akbari, M. E. (2020). A new formulation of polymer gel
dosimeter with reduced toxicity: dosimetric characteristics and radiological properties. Zeitschrift Fur
Medizinische Physik, 1–9. https://doi.org/10.1016/j.zemedi.2020.02.002
JOURNAL OF CRITICAL REVIEWS
ISSN- 2394-5125 VOL 7, ISSUE 16, 2020
872
[24] Singh, I., Sabharwal, A. D., Singh, B., & Sandhu, B. S. (2018). Study of Effective Atomic Number of
Muscle Tissue Equivalent Material Using Back-scattering of Gamma Ray Photons Experimental
evaluation of effective atomic number and gamma albedos of composite materials,medical samples and
alloys using multiple backscat. International Journal of Advanced Research in Science and Engineerng,
7(8), 141–145. https://www.researchgate.net/publication/327222536
[25] Tousi, E. T., Hashim, R., Bauk, S., Jaafar, M. S., Abuarra, A. M. H., & Ababneh, B. (2014). Some
properties of particleboards produced from Rhizophora spp. as a tissue-equivalent phantom material
bonded with Eremurus spp. Measurement: Journal of the International Measurement Confederation, 54,
14–21. https://doi.org/10.1016/j.measurement.2014.04.004
[26] Turşucu, A., Demir, D., & Önder, P. (2013). Effective atomic number determination of rare earth oxides
with scattering intensity ratio. Science and Technology of Nuclear Installations, 2013, 1–7.
https://doi.org/10.1155/2013/738978
[27] Wang, Y. (2006). Adhesive performance of soy protein isolate enhanced by chemical modification and
physical treatment. ProQuest Dissertations Publishing, 1–151.
[28] Zhang, X., Zhu, Y., Yu, Y., & Song, J. (2017). Improve performance of soy flour-based adhesive with a
lignin-based resin. Polymers, 9(7), 1–10. https://doi.org/10.3390/polym9070261
