Tikrit Journal of Pure Science 21 (3) 2016 ISSN: 1813 1662 (Print) [623161]

Tikrit Journal of Pure Science 21 (3) 2016 ISSN: 1813 – 1662 (Print)
E-ISSN: 2415 – 1726 (On Line)

49 Antimicrobial Activity of Zinc Oxide, titanium Dioxide and Silver
Nanoparticles Against Mithicillin -Resistant Staphylococcus aureus Isolates
Noura Burhan Aldeen Abdulrahman1 , Zainab Muhammad Nssaif 2
1 Department of Biology, College of Since, Tikrit University, Tikrit , Iraq
2 Department of Food Technology, College of Agriculture University of Salahelddin , Arbil , Iraq
Email: [anonimizat]

Abstract
The different investigation has been carried out on the biological activities of silver, zinc oxide and titanium
dioxide nanoparticles . But no study till now has identifie d the activity of particle s' size or type, nor a study has
proved their best synergism activity wit h antibiotics in one experiment against the same isolates.
In this study different siz es of the three types of nanoparticles (NPs) was used to detect the antibacterial activity
against methicillin resistant Staphylococcus aureus , which was isolated from patients (with burns and wound ) at
Erbil hospitals . Different antibiotics also, was evaluated against the same isolates. The Mithicillin -Resistant S.
aureus (MRSA ) isolates showed multidrug -resistant to most using antibiotics like; ampicillin, amoxicillin,
gentami cin, tetracycline clindamycin and erythromycin. The minimum inhibitory concentration (MIC) of these
antibiotics at then was conjugated with the nanoparticles' MIC to show the synergism effect by well diffusion
method .
The res ults showed that the phenotypic inhibition zones ha d been increased minimum 2 mm to maximum 18
mm, t hat confirmed the synergism activity when the antibiotics conjugated with NPs. These results signify that
these nanoparticle potentate the antimicrobial action of (bet a lactums, aminoglycosides, tetracycline, macrolid es
and lincosamide s) a possible utilization of nano compound in combination effect against MRSA .
Keywords : Nanoparticles, MRSA, Synergistic Effect.
Introduction :
Staphylococcus aureus is one of the most significant
human pathogens that cause both nosocomial and
community -acquired infections. The S. aureus strains
that resist methicillin and oxacillin have spread
worldwide. Infections with Mithicillin -Resistant S.
aureus (MRSA) strains, which resist a wide range of
antibiotics (multidrug -resistant), are associated with
considerable injury and mortality [1].
The emergence of bacterial resistance t o antibiotics
and its spreading are major health difficulties, leading
to treatment problems for a large number of drugs [2].
Thus there has been increasing interest in the use of
inhibitors of antibiotic resi stance for combination
therapy [3].
Metallic nanoparticles are attracting a gr eat deal of
attention because of their potential of succeeding
specific processes and selectivity, especially in
biological and pharmaceutical applications [4]. The
effective antimicrobial properties of these materials
are mainly due to their nanoparticles size, which
providing them unique chemical and physical
properties as increased surface to volume ratio and
high reactivity [5]. They act as Nano -antibiotics and
their potential of controlling infectious diseases have
been explored and demon strated by var ious
researchers.
Small particles exhibited higher antimicrobial activity
than big particles. That result can be due to high
particle penetration when the se particles have small er
sizes [6]. Silver, zinc and titanium have been used
mostly for the synthesis of stab le diffusions of
nanoparticles [7,8] .
Nowadays NPs are called “a wonder of modern
medicine”. The antibiotics can kill perhaps a half dozen different disease -causing organisms, whi le NPs
can kill some 650 cells [9]. The aim of this study
focus on using Nano -biotechnology for antimicrobial
chemo -dynamic therapy.
Material and Methods
Bacterial strains: S. aureus isolates investigated in
this study originated from the strain collection of
patient's burns and wounds at E rbil hospita ls. There
were about 53 isolates of S. aureus collected from
150 patients .
Antimicrobial susceptibility testing : Fifty three of
S. aureus isolates were tested by standard disc
diffusion method for the most used antibiotics:
ampicillin, amoxicillin, gentamicin, tetracycline ,
clindamycin and erythromycin ; according to NCCLS
(2006) [10]. Then, it had be en ensured by Vitek 2
compact system [11].
Tested Nanoparticles : The nanoparticles that used
was silver (Ag NPs) with size 20 nanometer, zinc
oxide (ZnO NPs) with size 20,30,50 -150 nanometer
and finally titanium oxide (TiO 2NPs) with size
10,50,100 nanometer prepared by M K Impex Corp.,
CANADA company. These NPs were set by the
company in a plastic freight with a stowage 100 gm.
as powder. The NPs stock solution were prepared by
adding 100 mg of NPs powder into 10 ml of
deionized water with h igh shaking to separate the
NPs a ccumulation for 5 min. to obtain a homogenous
solution which then, was sterilized by autoclaving
and left at room te mperature . The final concentration
was 10 mg \ml.
The Measurement of minimum inhibit ory
concentration of NPs and antibiotics :

Tikrit Journal of Pure Science 21 (3) 2016 ISSN: 1813 – 1662 (Print)
E-ISSN: 2415 – 1726 (On Line)

50 Minimum inhibitory concentration (MIC) is the
lowest concentration that inhibits the visible growth
of bacteria. The dilution by micro -titer plate method
was applied by using Muller Hinton broth to detect
the MIC of NPs depending on NCCLs in micro -titer
plate wells. By which the results that got from
dilution were in these concentrations : 2600, 1300,
650, 325, 162.5, 81.25, 40.6, 20.3 , 10.15, 5.07
microgram \ml. The microtiter plates were placed in
incubator overnight at 375C and the growth was
noticed after 18 hr in the wells. T he lowest
concentration that inhibited the visible growth of
bacteria was determined as MIC. The antibiotics '
MIC were obtained by the same way [12].
The m easurement of conjugated NPs with
antibiotic
A 0.1 ml of overnight bacterial suspension was
transported and spread onto Muller Hinton agar plates
after comparing it with McFarland No. 0.5 turbidity
standard, this solution has aspecific optical density to
provide a turbidity comparable to that of bacterial
suspension containing 1.5×108 CFU/ml . Four wells
were made on the plate with 5 mm diameter by sterile
boring cork. The MIC of NPs, which was determined
in the mentioned above steps was added to the well
No.1 and No.2 respectively. A 100 microliter (include
50 microliter of the antibiotic MIC that determined by
Micro Scan apparatus plus 50 microliter of NPs
together) were added into well No. 3, this well gave
the result of using conjugated NPs with antibiotic .
The distal water was added to the well No.4 to make
it as a negative control. The plates were incubated overn ight at 37 șC . The diameter of inhibition zones
around the wells was measured in mm. The test was
repeated to take the average of the effect [13].
Results and Discussion
Antimicrobial agents ' effect
The results revealed that from all 53 isolates, there
were 44 isolates (83 %) showed resistant to the
methicillin; while 7 isolates (13.2 %) were sensitive to
the methicillin and only 2 isolates (3.8 %) were
intermediate resistance to the methicillin. These
results agreed with the results of a local study by
Alhasani (2011) , who showed that the rate of
Methicillin resistance S. aureus (MRSA) was 81%
[14].
The isolates showed a high virulence for the used
antibiotics. All isolates was resistant to amoxicillin
antibiotic and there were 51 isolates (96,2 %)
resistant to ampicillin antibiotic , while only two
isolates (3, 8%) we re sensitive to it. The gentami cin
resistance result's was 88.6% which confirms Samir's
study (2007), who found that the rate of resistant to
Gentamicin in S. aureus was 80% [15]. The results
also showed decreasing in tetracycline susceptibility.
The rate of resistance was 94.3%, whereas one isolate
1.9% was intermediate . The resistance to other
antibiotics like clindamycin and erythromycin also
investigated in this study and the resul ts showed high
resistant of S. aureus isolates to both antibiotics in the
rate of resistance 40% and 51% respectively. The
antimicrobial agents results are cleared in the
Figure:1 .

Figure (1 -1) antimicrobial agents susceptibility.

A. Antimicrobial Effect of the Nanoparticles
Twelve of MRSA isolates that exhibited resistance to
the most common antibiotics like : ampicillin,
amoxicillin gentamycin, tetracycline, clindamycin
and erythromycin were in exposure of nanoparticles
to show their antimicrobial effect.
The Antimicrobial Ef fect of the Silver
Nanoparticles
The silver 20 nm showed a phenotypic inhibition on
agar plate 9 mm. That wa s obtained after measuring
its MIC by series of dilution method. The MIC
average was approximately 166 μg\ml. This results
agreed with Nilda Vanesa et al (2009 ), who noticed an antimicrobial activity ag ainst MRSA by using four
different sizes of Ag NPs [16].
Morones et al (2005) explained the antibacterial
activity of silver nanoparticles on Gram positi ve
bacteria, such as S. aureus , suggested that silver
nanoparticles attach to the surface of the cell
membrane and interrupt its function, penetrate
bacteria, and release silver ions [17,18].
Silver’s mode of action also, supposed to be
dependent on Ag+ ions, which strongly inhibit
bacterial growth thr ough suppression of enzymes,
electron transport system components and through
interference with DNA funct ions [19].

Tikrit Journal of Pure Science 21 (3) 2016 ISSN: 1813 – 1662 (Print)
E-ISSN: 2415 – 1726 (On Line)

51 The Antimicrobial Effect of the Zinc O xide
Nanoparticles
Zinc oxide 20 nm by the virtue of its MIC average
(256 μg\ml) in muller hinton broth, the inhibition
zones average was 11 mm. while ZnO 30 nm. showed
phenotypic inhibition zone average 7 mm on agar
plate at MIC average about 341 μg\ml. finally the
isolates showed sensitivity to ZnO 50 -100 nm in MIC
160 μg\ml. The inhibition zone was 9 mm.
These results agreed with Iram et al (2015) , who
observed the noticeable antibacterial activity of ZnO
NPs against S. aureus [20].
There are several mechanisms that have been
suggested to explain the antibacterial activity of ZnO
nanoparticles. The production of hydrogen peroxide
from the surface of ZnO is considered as an effective
mean for the inhibition of bacterial growth [21].
Another possible mechanism for ZnO antibacterial
activity is the release of Zn2+ ions that most likely
involve the disruption of the cell membrane lipids and
proteins that resulted in the leakage of intracellular
contents and eventually the death of cells [22]. The Antimicrobial Effect of the Titanium Dioxide
Nanoparticles
Depending to the isolates sensitivity to TiO 2 10 nm,
the MIC was (112 μg \ml) and the inhibition zones
average was 8 mm. while t he isolates showed
phen otypic inhibition zone average 7 mm on agar
plate at MIC average about 128 μg \ml for TiO 2 30
nm. Finally the isolates showed sensitivity to TiO 2 50
nm in MIC 128 μg\ml and the inhibition zone was 6
mm. These results confirm Roy et al (2010 ), who
detected the obvious antibacterial activity of the TiO
that tested on S. aureus [23].
The antibacterial activity of TiO2 that found perhaps
due to a reaction of the TiO2 surface with water. On
exposure to ultraviolet (UV) irradiation, TiO2
releas es fre e radicals such as OH, O-
2, HO-
2, and
H2O2, Which is regarded a potent oxidizing power
that usually results in circumstance of bacteria and
other organic substances [24]. The MIC of these
different types and sizes of nanoparticles are in
table:1 .
Table (1) The MIC & Inhibition zone of NPs.
_ Ag
20 nm ZnO
20 nm ZnO
30 nm ZnO
100 nm TiO
10 nm TiO
30 nm TiO
50 nm
MIC 166
μg\ml 256
μg\ml 341
μg\ml 160
μg\ml 112
μg\ml 128 μg\ml 128 μg\ml
I Z 9 mm 11mm 7 mm 9 mm 8 mm 7 mm 6 mm
IZ = inhibition zone

B. The Study of the Synergistic E ffects of the
Nanoparticles with Antibiotics
The MIC of the antibiotics that exhibited inactivity
against the isolates was conjugated with the MIC of NPs to study their effects together by well diffusion
method. The relationship between these antibiotics &
nanoparticles is describe d in the below table (Table 2).

Table (2) The effect of conjugated NPs with Ab.
Ab. IZ The effect of conjugated NPs with Ab. (mm)

–- Ab. E. Ag
20 nm ZnO
20 nm ZnO
30 nm ZnO
50 nm TiO
10 nm TiO
30 nm TiO
100 nm
Am 0 11 15 12 16 18 13 16
AX 0 9 12 11 11 10 11 9
GM 6 19 20 18 14 11 11 10
TE 2 6 9 6 7 10 7 6
CA 8 17 18 20 19 15 12 12
E 2 19 18 20 21 13 11 14

The results showed that the average of inhibition
diameter increased when the antibiotic MIC
compacted with the different sizes of the NPs MIC.
This suppo rted Faya z et al (2010), who noticed that
the NPs mini size enable it to penetrate the microbe
membrane cell [25]. Robert et al (2013), also
confirmed that the activity of the Ampicillin and
amoxyclav will increase if the Silver (Ag+) NPs
concentration incr eases. That' s led to in hibit the two
type of bacteria (Gram positive and negative). Other
study mentioned that the activity of Gentamicin
increases against S. aureus when it compacted with
(Ag+) NPs [26]. The results of the synergism effect of Ag NPs with
Tetracycline and Erythr omycin also exhibited an
increasing in their inhibition zone. The increasing in
diameter length was approximately about 4 mm and
17 mm respectively, while Zarina et al (2014) found
that the diameter of the inhibition area s for the same
antibiotics increased about 2mm and 3mm
respectively [27]. Moreover, the antibacterial
activities of clindamycin were increased in the
presence of Ag -NPs against the isolates. The result
showed that the inhibition zone enlarged about 9 mm.
This is support Ahmad 's et al (2007) , who found
increasing of the NPs activity after it comp acted with
clindamycin [28].

Tikrit Journal of Pure Science 21 (3) 2016 ISSN: 1813 – 1662 (Print)
E-ISSN: 2415 – 1726 (On Line)

52 The results also showed a noticible synergistic effect
when some of the mentioned antibiotics compacted
with the different sized of Zinc Oxide (ZnO)
Nanoparticles, as explained in (table 2).
Bhande et al (2013) showed that the effects of the
antibiotics rise if they will conjugate with the Zinc
Oxide (ZnO) Nanoparticles [29]. It was easily to
notice their activity against the bact eria that resist
wide spectrum ampi cillin, which could cause urinary
tract infections. This study also suggested that the
conjugation of Zinc Oxide (ZnO) Nanoparticles with
the antibiotics increase the permeability of the
bacterial plasma membrane, that enable the plasma
protein flowing out of the cell throw the interrupted
cell membrane.
Similarly, erythromycin conjugated ZnO particles
gave the same smart results of enlarging in inhibition
area. This is also, support Iram et al (2015), who
found that erythromycin conjugated ZnO NPs (≤50nm) lowered the MIC of his resistant strains of S.
aureus [20].
The observous increasing of inhibition zone When
the gentamycin conjugates with ZnO supports Voicu
et al (2013), who detect by his bact eriological tests
the a synergistic activity of ZnO -gentamici n
nanoparticles [30].
The two clindamycin and Tetracycline also exhibited
an inhibti onal activity against S. aureus . Clindamycin
showed a high inhibition zone When it comjugated
with ZnO 30 nm.
TiO2 effect alone was somehow low, while it exibted
an obsorvious defference when conjugated with the
antibiotics. The results showed that the effect of TiO2
NPs was very close to Roy et al (2010) [23]. He
found that the increasing in effect after it conjugated
with the antibiotics as follows: with a mpicillin and
gentamycin 9 mm, with amoxicillin 7 mm, with
erythromycin and clindamycin 6 mm and finally with
tetracycline 5 mm.
References
[1] Y.A. Liu, H. Wang, N. Du, E . Shen , H. Chen and
J. Niu, Molecular evidence for spread of two major
methicillin -resistant staphylococcus aureus clones
with a unique geographic distribution in chinese
hospitals . Antimicrob Agents Chemother. 53 (2009)
512-518.
[2] G.C. Schito. The Importance of the development
of antibiotic r esistance in Staphylococcus .aureus .
Clin Microbiol Infect . 12 (2006) 3-8.
[3] G.D. Wright. Resisting resistance: new chemical
strategies for battling superbugs. Chemistry and
Biology . 7 (2000) 127-132.
[4] P. Li, J. Li and Q. Wu. Synergistic antibacterial
effects of lactam antibiotic c ombined with silver
nanoparticles. J. Nanotechnol . 16 (2005) 1912 -1917.
[5] E. Weir, A. Lawlor, A. Whelan and F. Regan . The
use of nanoparticles in anti -microbial materials and
their characterization . Analyst. ;133 (2008) 835-845.
[6] G.A. Martínez -Castañón, N. Niño -Martínez , F.
Martínez -Gutierrez , J.R. Martínez -Mendoza and F.
Ruiz . Synthesis and antibacterial activity of silver
nano particles with different sizes. J Nanoparticle Res .
10 (2008) 1343 -1348.
[7] A.M. Smith, H. Duan, M.N. Rhyner, G. Ruan, and
S.A. Nie. Synthesis of Gold Nanopartic les Bearing
the Bioconjugation. Phys Chem Chem Phys . 8
(2006) 3895.
[8] G.J. Kear ns, E.W. Foster and J.E. Hutchison.
Substrates for direct imaging of c hemically
functionalized SiO 2 surfaces by transmission electron
microscopy. Anal Chem . 78 (2006) 298.
[9] T. Sungkaworn, W. Triampo, P. Nalakarn, D.
Triampo, I.M. Tang and Y. Lenbury . The Effects of
TiO 2 nanoparticles on tumor cell colonies: fractal
dimension and morphological p roperties . Int J
Biomed Sci . 2 (2007) 67-74.
[10] NCCLs National Committee for Clinical
Laboratory Standards (2006). Performance standards for antimicrobial Susc eptibility testing. NCCL S
approved standard M100 – S16.
[11] M. Ligozzi, C. Bernini, M.G. Bonora, M. de
Fatima, J. Zuliani, and R. Fontana. Evaluation of the
VITEK 2 system for identification and antimicrobial
susceptibility testing of medically relevant gram –
positive cocci, ” J. Clin. Microbiol . 40 (2002) 1681 –
1686.
[12] B. Guigna rd, J. Vouillamoz, M. Giddey and P.
Moreillon . A positive interaction between inhibitors
of protein synthesis and cefepime in the fight against
methicillin -resistant Staphyloc occus aureus . Eur. J .
Clin. Microbiol. Infect. Dis. (2013).
[13] C. Ding . Effect of antibiotics in the environment
on microbial populations . Appl. Microbiol.
Biotechnol. 87 (2010) 925-941.
[14] H. M. Al-Hasani. Comparative Study between
Methicillin -Resistant Coagulase Positive and
Negative Staphylococci. M.Sc. Thesis. College of
Science. Diyala University . (2011) , Diyala, Iraq. 33-
80.
[15] R.A. Samir. A study of antibiotic and heavy
metal resistance in Staphylococcus aureus isolates
from clinical spe cimens. M.Sc. Thesis. College of
Science. Al -Nahrain University, (2007) Baghdad,
Iraq. 13 -98.
[16] V.A. Nilda , H.L. Humberto, L.C. Turrent and
C.R. Padilla. Silver nanoparticles toxicity and
bactericidal effect against methicillin -resistant
Staphylococcus aureus . Nanoscale Does Matter .10
(2009) 1007 .
[17] J.R. Morones, J.L. Elechiguerra, A. Camacho, K.
Holt, J.B. Kouri, and J. Tapia. The bactericidal effect
of silver nanoparticles . Nanotechnology . 16 (2005)
2346 -2353.
[18] S. Shrivastava, T. Bera, A. Roy, G. Singh, P.
Ramachandrarao, and D. Dash. Characterization of
enhanced antibacterial effects of novel silver
nanoparticles . Nanotechnology . 18 (2007) 1-9.

Tikrit Journal of Pure Science 21 (3) 2016 ISSN: 1813 – 1662 (Print)
E-ISSN: 2415 – 1726 (On Line)

53 [19] Y. Li, P. Leung, L. Yao, Q.W. Song and E.
Newton. Antimicrobial effect of surgical masks
coated with nanoparticles. J Hosp Infect . 62 (2006)
58-63.
[20] S. Iram, A. Nadhma, N. Akhtar, A. Hameed, Z.
Zulfiqarand and A.M. Yameen . Potential efficacy of
antibiotic conjugates with zinc oxide nanoparticles
against clinical i solates of Staphylococcus aureus .
Digest Journal of Nanomaterials and Biostructures .
10 (2015) 901-914.
[21] O. Yamamoto. Influence of particle size on the
antiba cterial activity of zinc oxide. Int. J. Inorg.
Mater. 3 (2001) 643-646.
[22] Y. Xie, X. Shi, Y. He, P.L. T.I. Jin, Antibacterial
activity and mechanism of action of zinc oxide
nanoparticles against Campylobacter jejuni . App
Environmental Microbiol. 77 (2011) 2325 -2331.
[23] A.S. Roy, A.P. Koppalkar and M.V.N. Ambika .
Effect of Nano – titanium dioxide wit h different
antibiotics against m ethicillin -resistant
Staphylococcus aureus . Journal of Biomaterials and
Nanobiotechnology . 1 (2010) 37-41.
[24] K. Shiraishi, H. Koscki, et al . Antimicrobial
metal implant with a TiO 2-conferred photocatalytic
bactericidal effect against Staphylococcus aureus .
Surf. Inter. Anal . 41 (2008) 17-21.
[25] A.M. Fayaz, K. Balaji, M. Girilal, R. Yadav,
P.T. Kalaichelvan, and R. Venketesan . Biogenic synthesis of silver nanoparticles and their synergistic
effect with antibiotics: A study against gram -positive
and gramnegative bacteria. Nanomed Nanotech Biol
Med. 6 (2010) 103-109.
[26] R.Y. Pelgrift and A.J. Friedman .
Nanotechnology as a therapeutic tool to combat
microbial resistance . Nanotechnology and drug
resistance . 65 (2013) 1803 -1815.
[27] A. Zarina, and A . Nanda. "Green Approach for
Synthesis of Silver Nanoparticles from Marine
Streptomyces – MS 26 and Their Antibiotic Efficacy",
Department of Biomedical Engineering, J. Pharm.
Sci. & Res . 6 (2014) 321-327.
[28] A.R. Shahverdi, A . Fakhimi, H .R. Shahverdi and
S. Minaian. Synthesis and effect of silver
nanoparticles on the antibacterial activity of different
antibiotics against Staphylococcus aureus and
Escherichia coli . Nanotechnology, Biology and
Medicine . 3 (2007) 168-171.
[29] R.M. Bhande, C.N. Khobragade, R.S. Mane and
S. Bhande . Synergism of antibiotic with zinc oxide
nanoparticle against extended spectrum B -lactam ase
producers implicated in u rinary tract i nfections . J
Nanoparticle Res. 15 (2013) 1413 -1417.
[30] G. Voicu , O. Opera , B.S Vasile , E. Andronescu.
Antibacterial activity of zinc oxide –gentamicin
hybrid material. Digest Journal of Nanomaterials
and Biostructures . 8 (2013) 1191 -1203.

فعالية دقائق الفضة ، أوكسيد الزنك و ثنائي أوكسيد التيتانيوم النانوية ضد عزالت المكورات العنقودية
الذهبية المقاومة للميثيسيلين
نورا برهان الدين عبدالرحمن 1 ،زينب محمد نصيف 2
1 قسمعلوم الحياة ، كلية العلوم ، جامعة تكريت ، تكريت ، العراق
2 قسم الصناعات الغذائية ، كلية الزراعة ، جامعة صالح الدين ، اربيل ، العراق

الملخص
أن بحوث عديدة حملت على عاتقها دراسة التأثير النانوي لدقائق الفضة وثنائي أوكسيد التيتانيوم وأوكسيد الزنك على البكتريا , لكن أيا منها لم يحدد
الفعالية األكفأ لحجم ما أو نوع ما من أنواع هذه الدقائق دونما غيره, كما لم يثبت أكفأ فعالياته التآزرية مع المضادات الحيوية في تجربة واحدة وعلى
العزالت ذاتها.
في هذه الدراسة أختبرت األنواع الثالثة لهذه الدقائق وبأحجام مختلفة لتحديد النوع االكثر فعالية و تركيزه المؤثر على بكتريا المكورات العنقودية
الذهبية المقاومة للمثيسيلين و المعزولة من حروق وجروح المرضى الراقدين في مستشفيات أربيل . وتم اختبار فحص الحساسية ايضا لهذه العزالت
لغرض تحديد المضادات التي تقاومها البكتريا, فوجد انها مقاومة أل كثر المضادات شيوعا في االستخدام كمضادات االمبسلين, االموكسيسيلين,
الجنتاميسين, التيتراسايكلين, الكليندامايسين و االيرثروميسين .
كما تم تحديد التركيز المثبط االدنى للدقائق والمضادات التي قاومتها البكتريا من خالل سلسلة من التخافيف , ومن ثم تم دمج هذين التركيز ين
لمالحظة التأثير التآزري للمضاد مع الدقائق النانوية من خالل انتشارها من حفر وسط النمو well diffusion method , وأظهرت مناطق تثبيط
ظاهرية بأ قطار تفوق اقطار تثبيط المضاد وحده أو الدقائق النانوية وحدها بزيادة ملحوظة يتراوح مقدار ها 2 – 18 مليمتر مما يثبت التأثير التآزري
لهذه االنواع من الدقائق مع مضادات مجاميع : beta lactums , tetracycline , aminoglycosides , macrolids واخيرا مجموعة
lincosamides .
الكلمات المفتاحية: الدقائق النانوية , المكورات العنقودية الذهبية المقاومة للميثيسيلين , الفعالية التآزرية