N. Farahani, M. Behmanesh, B. Ranjbar,
Volume 10, Issue 3 (9-2019)
Abstract
Aims: Due to their unique properties, functionalized GNPs provide a high potential for solving many problems, such as diagnosis and treatment of genetic diseases using nanotechnology. Depending on the purpose of each experiment, a particular interaction of DNA and nanoparticle is desirable that can be achieved by changing various parameters. The purpose of this study was to investigate the effect of gold nanoparticles surface charge on the conjugation process and the type of DNA interactions, as well as increasing the loading of DNA on the surface of gold nanoparticles.
Materials and Methods: Two types of 30nm gold nanoparticles with positive and negative charge were synthesized. Gold nanoparticles were functionalized with three different concentrations of DNA. Bioconjugation was investigated using UV-Vis and fluorescence spectroscopy. Quantification of the DNA loading on each nanoparticle surface was done using two methods by fluorescence assay.
Findings: The SPR spectrum of nanoparticles confirmed the binding of DNA to the surface of nanoparticles and also illustrates the level of DNA loading to the surface of the nanoparticle, as well as the effect of the surface charge of nanoparticles on the bioconjugation process. The fluorescence assay showed a higher loading of DNA in CTAB-stabilized nanoparticles and more non-specific than citrate-stabilized nanoparticles.
Conclusion: Depending on the surface charge of GNPs, DNA loading on the surface of GNPs occurs with different affinities. Based on the purpose of the study, citrate stabilized GNPs and high concentration of DNA was appropriate to achieve this goal.
F. Hajipour, S. Asad, M.a. Amoozegar, Kh. Khajeh,
Volume 10, Issue 3 (9-2019)
Abstract
Quantum dots have received great attention for the past years as fluorescent markers for physical, chemical, and biological applications due to their unique size-dependent electrical and optical properties such as high extinction coefficient, broad absorption with narrow symmetric size-tunable fluorescent spectra, and strong resistance to photobleaching with significant luminescence quantum yield. In this study, at first the CdSe/ZnS quantum dots coated with oleylamine surface ligand were synthesized by high temperature injection method under vacuum conditions and stable nitrogen at 320°C. Then, in order to investigate the quenching effect of azo dyes, which is one of the most carcinogenic chemical colors used in various industries, on the emission of these nanoparticles, we used mercaptopropionic acid as a suitable hydrophilic ligand at the surface modification of quantum dots in the ligand exchange process as a proper aqueous phase transfer strategy. After confirming the proper synthesis of CdSe/ZnS nanoparticles by the transmission electron microscopy (TEM) test and the synthesized nanoparticle core and shell standard powder diffraction files (pdfs) in X-ray diffraction (XRD), the results of the studies showed that the methyl red due to its absorption spectrum overlapping with the emission spectrum of these quantum dots has a very powerful quenching effect on the emission of synthesized nanoparticles.
S. Zaghian, T. Tohidi Moghadam, M. Behmanesh,
Volume 10, Issue 3 (9-2019)
Abstract
The unique physicochemical properties of nanoscale plasmonic materials have attracted considerable attention in the fabrication of hybrid nano-bio structures because of their promising applications in biosensing, imaging, and controlled-release drug delivery. The purpose of this study was the synthesis of functionalized gold nanorods (GNRs) to both reduce the toxicity and increase the biocompatibility for further applications such as the design of a therapeutic nanocarrier for nucleic acid delivery to cancerous cells. In this study, GNRs were prepared by seed-mediated method and their surface was modified by polystyrene sulfonate (PSS) polymer. Then, peptide-functionalized GNRs was fabricated via ligand exchange method through the Au-S bond. The CTAB-GNRs and functionalized nanostructures were characterized using ultraviolet-visible spectrophotometry, transmission electron microscopy (TEM), and zeta potential measurement. Finally, the cytotoxicity effects of functionalized GNRs on Hela cells were studied by MTT assay. The optimal concentration of PSS and peptide, which did not cause any aggregation and morphological perturbations of the nanostructure were obtained 50μM and 1mM respectively. The survival percentage of treated Hela cells significantly increased by surface modification of GNRs with PSS and functionalization with peptide compared to CTAB-GNRs. While LC50 of functionalized GNRs was calculated 50nM, treated cells with the same concentrations of CTABGNRs survived less than 20%. Functionalization of GNRs increases its biocompatibility and improves applications of this nanostructure as a therapeutic carrier in cancerous cells.
E. Abdolmajid, F. Nemati,
Volume 10, Issue 4 (12-2019)
Abstract
Aims: The objective of this research was to develop a novel method for the synthesis of colloidal solutions of titanium dioxide nanoparticles with high stability and life span.
Materials & Methods: Based on mentioned points, the issue of this study is the synthesis of nanoparticles via chemical reduction process. The morphologies, compositions, and physicochemical properties of the prepared samples were characterized by TEM, XRD and DLS. Also, the cytotoxic effect of fabricated NPs against human white blood cells (WBCs) was investigated via MTT assay. In addition, antibacterial activity was investigated.
Findings: The results of this study indicate that the diameter of the synthesized nanoparticles is about 50nm and contains the anatase phase, in the range of 2θ from 25-80°C, and the hydrodynamic radius of nanoparticles is about 95.8±12.78nm and the zeta potential of nanoparticles is about -34.87±4.78mV. Also, the effect of toxicity of titanium dioxide nanoparticles on the white blood cell line showed that these nanoparticles cause the toxicity of cells at concentrations above 200μg/ml, but in lower concentrations, normal cells can survive. Also, these nanoparticles at the same low concentrations.
Conclusion: In conclusion, colloidal solutions with high stability were successfully synthesized, which, in addition to increasing the antibacterial properties due to diminished dimensions.
Z. Safari, S. Soudi, A. Zavaran Hosseini, H. Bardania, M. Sadeghizadeh ,
Volume 10, Issue 4 (12-2019)
Abstract
Aims: One of the most important regenerative medical purposes is the production of alternative tissues with proper function. Fibroblast cells are one of the most important types of cells in the repair process that also play a role in the formation of blood vessels. Stimulation of fibroblastic cells requires the appearance of external signals to begin the proliferation and recall of other cells, as well as angiogenesis. The aim of this study was to investigate the effects of M13 in combination with RGD peptide on fibroblastic cells.
Materials and Methods: For this study, M13 bacteriophage was first amplified and isolated. Then RGD peptide was synthesized and purified. Then, isolated mouse fibroblastic cells were culture on surfaces coated with M13 bacteriophage, bacteriophage M13 and RGD, gelatin, and surfaces without coated as a control for 48 hours. MTT assay was used to measure the proliferation and survival of cells, and then the expression of FGF-2, TGF-β1 and VEGF-A genes was measured by real-time PCR.
Findings: The results of this study showed that the M13 and RGD bacteriophage increased cell proliferation and the fibroblast cell survival rate. In addition, expression of FGF-2, TGF-β1 and VEGF-A genes in cultured fibroblasts on the M13 and RGD bacteriophages surface increased significantly.
Conclusion: Our research showed that scaffolds of M13 bacteriophage and RGD peptide are nontoxic and bio-compatible so they can be a suitable candidate for induction of repair and angiogenesis in tissue engineering.
H. Hashemzadeh, A. Allahverdi , P. Ertl, H. Naderi-Manesh,
Volume 10, Issue 4 (12-2019)
Abstract
In view of the constant increase of nanotechnology and nanomaterials applications in our daily life, to determine whether they are safe, “in vitro” and “in vivo” screening methods are needed. Obviously, application of models that are similar to the physiological tissues process of the human body could be a better candidate. The three-dimensional spheroid method, spheroid were generated using commercial microplates, has many benefits (in comparison with traditional methods or monolayer cell culture) such as the growth of the cells in 3D, similar to the body's physiological tissue, an alternative for animal models, cell-to-cell interactions, and better cell signaling. In this study, the toxicity of silver nanoparticles by using three factors such as metabolic activity, live/dead assay, and spheroid surface area was evaluated using two different methods (2D vs 3D) under treatment with various concentrations of silver nanoparticles at different times. The results showed that different cells types, cancer and/or normal lung cells, have significant differences. In addition, it was observed that distinct differences in terms of cytotoxicity of silver nanoparticles between 2D and 3D culture systems and also the rate of growth/non-growth of spheroids are highly depended on cell type and various concentrations have fundamental importance in such studies. The present study provides evidence that cellular dimensions (3D vs 2D) play a pivotal role in the results and outcomes of inflammation and cytotoxicity with nanoparticles due to the spatial-temporal structure.
J. Esfandyari, B. Shojaedin-Givi, M. Mozafari-Nia, H. Hashemzadeh, H. Naderi-Manesh,
Volume 10, Issue 4 (12-2019)
Abstract
Diatoms biosilica shell, frustule, is substitute biostructures to mesoporous silica particles, which possesses their wide surfaces, nano-diameter porosity, mechanical strength, and thermal stability, optical capabilities, and the ability to bind to biomolecules can be used in biosensing applications. In this study, diatom species called Chaetoceros muelleri, was used for the fabrication of the Fe2O3-Au-Biosilica magnetic package. After micro-algae cultivation, the synthesis of gold nanoparticles (AuNPs) on silica walls was carried out using the bio-synthesis method, which evaluations have demonstrated the continuous formation of spherical AuNPs on the walls and its surfaces. After this step, the magnetic iron oxide nanoparticles were attached to the silica surface of the diatom, this, in turn, leads to system guiding using a magnetic field. Surface modification of diatoms magnetic complex, by using the APTES, allowed the attachment of fluorescence Rhodamine and the Herceptin antibody (Trastuzumab) to the structure. As well as the attachment of the fabricated system to target cells (SKBR3) was confirmed by fluorescence microscopic analysis. The results of this study indicate the ability and specificity of the diatom silicone shell as a "multipurpose" package for diagnostic and therapeutic activities.
S. Karimian Bahnamiri, A. Maghsoudi, F. Yazdian,
Volume 10, Issue 4 (12-2019)
Abstract
Aims: Curcumin is a natural molecule that due to its various curative effects including antibacterial properties, it can be used as a medicine, albeit after reducing its disadvantages. The aim of the present study is to develop a method for preparation of nanoparticles of curcumin using PAA, PVA, and PEI polymers with a view to improve its stability, increasing bioavailability and aqueous solubility as well as study its effectiveness against methicillin-resistant to Staphylococcus aureus.
Materials & Methods: In order to synthesize polymeric nanoparticles including curcumin with the nano-precipitation method, optimizing the effective concentration of polymer, curcumin, and water were determined by using the Response Surface Method (RSM). Synthesized nanoparticles were characterized by Scanning Electron Microscope (SEM), Dynamic Light Scattering (DLS) and zeta potential measurement methods. Furthermore, minimal concentration inhibitory of synthesized nanoparticles against the Staphylococcus aureus resistant to methicillin was measured.
Findings: The created nanoparticles were round, discrete and smooth in surface morphology and the average particle size for PAA, PVA, and PEI were 149±7nm, 175±8nm, and 184±9nm respectively. The minimum inhibitory concentration for PAA, PVA and PEI nanoparticles against the Staphylococcus aureus were 0.480±0.024, 0.390±0.019 and 0.340±0.017mg/ml. The concentration of solvent, polymer, and curcumin was important to obtain small size particles.
Conclusion: The results indicated that the water solubility of curcumin significantly improved by particle size reduction up to the nano range. The inhibitory property of curcumin nanoparticles has greatly increased due to the smaller particle size and their increased penetration into the bacteria and nanoparticles loaded with curcumin could be a promising drug carrier for the treatment of cancer, infections and other diseases.
S.s. Mirjalili, T. Tohidi Moghadam, R. Hassan Sajedi ,
Volume 10, Issue 4 (12-2019)
Abstract
Recent researches on the application of nanoparticles have been focused on nanostructures of gold with rod morphology, due to having outstanding optical properties for diagnostics and therapeutics of the diseases. The rod morphology of the nanostructures enables strong and sensitive absorption of surface plasmon in the infrared region. In the present research, based on the sensitivity of surface plasmon resonance of gold nanorods to trace changes in the local environment, as well as the importance of rapid detection of trace amounts of albumin in urine, functionalization, and stability of these nanostructures with anti-albumin antibody has been investigated in different concentrations, volumes, time and pH changes. The results of spectroscopic studies of different samples in the visible spectrum near-infrared waves showed that gold nanorods have desirable stability, and their rod morphology characteristic is maintained. The study of the temporal stability of samples showed that the complex samples were stable up to 48 hours for sensing applications. Primary monitoring of the function of the nanobiosensor in the presence of albumin with two normal and abnormal levels of concentration revealed remarkable changes in interparticle distance, size, and morphology of the nanostructures. According to this research, the rod nanostructures can be used to design simple nanobiosensors.
Bahare Mehrdad Vahdati, Alimorad Rashidi, Hossein Naderi-Manesh, Behnam Rasekh,
Volume 11, Issue 1 (3-2020)
Abstract
Graphene quantum dots (GQDs) have attracted increasing attention due to their unique properties such as high water solubility, photoluminescence activity, good biocompatibility, physical, chemical and electrical properties which makes them appropriate candidates for use in a variety of bio-applications, sensors and photocatalysts. The objective of this study is synthesis of GQDs and improving their surface properties via chemical modification.
Here, urea and citric acid as carbon precursor were used. Citric acid was self-assembled into graphene framework via hydrothermal method at 160 °C for 4 h. Then, the synthesized GQDs were carbonized and chemically activated by KOH treatment. The surface area and pore structures of GQDs were analyzed by nitrogen adsorption/desorption isotherms. The results showed that the specific surface area of carbonized-activated graphene quantum dots (CA-GQDs) have been increased from 0.06 to 1204.0 m2/g and pore structures have been enhanced significantly. The XRD pattern of GQDs confirmed the basic structure of graphite layer. The TEM images indicated the unique morphology of GQDs and the sizes of GQDs were less than 5 nm. Thus, our applied method is an effective approach in the formation of GQDs with large BET surface area and narrow pore structures which reveals their potential applicability in biomedical field.
Shabnam Roshani, Hamide Ehtesabi, Zeinab Bagheri,
Volume 11, Issue 1 (3-2020)
Abstract
Mercury is one of the most harmful pollutants in the environment, which in the event of ingestion into the human body, it is not metabolized and severe nervous, respiratory and metabolic disorders will occur due to the formation of stable complexes with biological molecules. Therefore, the development of precise, fast and inexpensive methods for mercury detection in the environment is of great importance. Carbon quantum dot is a new fluorescent substance with unique physical and chemical properties which is taken into consideration for diagnostic applications, especially for heavy metals detection at low concentrations. In this study, carbon dots with blue fluorescent emission were synthesized using the pyrolysis method and characterized. Fluorescent emission intensity of synthesized carbon dots was decreased significantly in interacting with mercury. Then for providing an easy-to-use mercury detection method, carbon dot was encapsulated in sodium alginate hydrogel. Quenching fluorescent intensity of encapsulated carbon dots in the hydrogel structure was evaluated in the presence of mercury and 1micromolar detection limit was obtained. Encapsulating carbon dots in hydrogel structure not only extend the use of carbon dot as a mercury sensor but also can be used as an adsorbent for mercury pollutant from the environment.
Sheyda Jahazi, Hashem Yaghoubi, Hossein Akbari,
Volume 11, Issue 2 (6-2020)
Abstract
Iron oxide nanoparticles are one of the nano carriers that are suitable for novel drug delivery systems due to low toxicity, biocompatibility, loading capacity and controlled drug delivery to cancer cells. The purpose of this study is the synthesis of coated iron oxide nanoparticles for delivery of Doxorubicin (DOX) and its effects on cancer cells.
In this study, Fe3O4 magnetic nanoparticles were synthesized by Polyol method, and then doxorubicin was loaded onto PEGylated iron oxide nanoparticles. FT-IR was used to ensure PEG binding to nanoparticles and loading the drug onto nanoshell. Comparison of the mean size and the crystalline structure of nanoparticles were performed by TEM and X-ray diffraction pattern. Then, the effect of cytotoxicity was evaluated on AGS and MCF-7 cancer cells by MTT assay.
According to FT-IR results, the presence of O-H and C-H bands at 2927 cm-1 and 3392 cm-1 peaks correlated with PEG binding to nanoparticles. XRD pattern showed the cubic spinel structure of trapped magnetite nanoparticles carrying medium with a mean size of 14 nm. 21.67% of Doxorubicin was loaded into Fe3O4-PEG nanoparticles, which the highest drug release recorded during the first 24 hours. MTT assay at 24, 48 and 72 h treatments showed that with increasing concentrations of doxorubicin loaded Fe3O4-PEG nanoparticles from 0 to 50 μm, the cytotoxic effects of the drug gradually increase.
This study showed that PEGylation of iron oxide nanoparticles and using them in drug delivery process to increase the effect of Doxorubicin on AGS and MCF-7 cancer cells
Nasrin Fazelian, Morteza Yousefzadi, Ahmad Ahmadi,
Volume 11, Issue 2 (6-2020)
Abstract
Objectives: In this study, the effect of different concentrations (1-50 mg/L) of colloidal Ag-NPs investigated on the growth, fatty acids profile and biodiesel indices of N. oculata, after estimating EC50 (20.88 mg/L).
Materials and methods: In this research, N. oculata was selected owing to fast growth and its ability to synthesize lipids for biodiesel production. This microalga exposed to colloidal silver nanoparticles under marine conditions for 72 h. The optical density (OD) and fatty acid profiles were investigated using spectrophotometric analysis and gas chromatography, respectively. Statistical analysis growth data was performed using ANOVA and Duncan's multiple test at 2% probability level.
Results: The algal growth significantly decreased in N. oculata cells treated with the 5-50 mg/L of Ag-NPs. The increase of saturated fatty acids (SFAs) and polyunsaturated fatty acids (PUFAs) as well as the decrease of monounsaturated fatty acids (MUFAs) contents were also observed in response to 25 mg/L of Ag-NPs in compared to the control. The important indicators of biodiesel oxidative stability containing LCSF, CFPP and CP increased in N. oculata exposed to Ag-NPs, while the level of DU decreased. The results of this study showed that despite the toxicity of silver nanoparticles, this nanoparticle can increase the biodiesel stability produced from N. oculata.
Fezzeh Amani, Tahereh Tohidi Moghadam, Zeinab Bagheri, Nasrin Farahani, Bijan Ranjbar,
Volume 11, Issue 2 (6-2020)
Abstract
Aptamers, DNA or RNA single-stranded sequences, have different applications in biological investigations, such as apatsensors, due to their many advantages including high specificity and affinity, cost-effectiveness and easy synthesis. In this study, an aptasensor was designed based on the changes in the SPR spectra of gold nanoparticle, in order to detect carcinoembryonic antigen (CEA) cancer indicator as a marker for breast cancer. In the presence of aptamer, gold nanoparticles were stable, SPR spectrum of gold nanoparticle was unchanged after adding NaCl. However, in the presence of CEA as a cancer marker, aptamer binds to the target molecule and by adding NaCl consequently the SPR spectrum of gold nanoparticles is changed. The results of this study showed that the designed aptasensor enables the detection of CEA over a range of 50 ng ml-1. The limit of detection was about 22.75 ng ml-1. It seems this aptasensor can be used in detection of carcinoembryonic antigen cancer marker.
Mohammad Tohidlou, Sanam Sadeghi Mohammadi, Zahra Vaezi, Majid Taghdir, Hossein Naderi-Manesh,
Volume 11, Issue 4 (11-2020)
Abstract
Chemotherapy is one of the most effective and common treatments for cancer. Multi-drug resistance and drug side effects are one of the major obstacles to successful chemotherapy. To address these limitations and achieve better drug efficacy, nanosystem-based combination therapy offers a promising approach. This study aimed to synthesize, characterize, and investigate the synergistic effect of nanoliposomes loaded with doxorubicin and epigallocatechin-3-gallate (EGCG) on MCF-7 breast cancer cell lines. In the present study, nanoliposomes were prepared by passive loading and thin-film hydration. The characterization of nanoliposomes such as size distribution, zeta potential, the loading rate, drug release profile, and toxicity were measured. The mean diameter of nanoliposomes was 82.5 nm, their surface charge was -24.2 mV and drug loading was about 80%. The interaction of doxorubicin and EGCG with nanoliposomes was mediated by electrostatic and van der Waals bonds and EGCG has a deceasing effect on the doxorubicin release profile but the observed differences are not significant. The toxicity and viability data indicate that the simultaneous use of these two drugs increased the toxicity of the cells. Nanoliposomes containing doxorubicin were not able to reduce viability to below 50% in monotherapy with 5×10-3 μM. While, the amount of viability dramatically reduced to below 50%, in combination with EGCG, resulting as combination chemotherapy. Consequently, the concomitant administration of EGCG with doxorubicin may be a suitable candidate for chemotherapy.
Arezoo Golestanipour, Ali Aalami, Maryam Nikkhah, Saman Hosseinkhani,
Volume 11, Issue 4 (11-2020)
Abstract
Developing a technique for efficient and safe gene delivery to plant cells is a fundamental aim of plant biotechnology. Agrobacterium mediated transformation as the most common and practical method in plant gene delivery has considerable difficulties such as limitation in applicable for plant species. In recent years several new methods have been suggested, although none of them could be a good replacement. The use of nanotechnology has been provided new solutions to overcome the limitations of biotechnology. Designing biocompatible nanostructures for passing cell barriers and targeted delivery of cargo has improved the biological achievements. In this research the capability of arginine functionalized single-walled carbon nanotube (Arg-SWNT) as a new carrier to transfer plasmid DNA, which codes green fluorescent protein (GFP) to tobacco suspension cells, has been investigation. It is suggested that single-walled carbon nanotubes can pass through cell wall pores and plasma membrane while it carries plasmid DNA along with. The fluorescence microscopy images illustrate the success of gene delivery by Arg-SWNT
Soheila Takavar, Majid Sadeghizadeh, Heshmatollah Rahimian, Gholamreza Esmaeeli Djavid,
Volume 12, Issue 1 (12-2020)
Abstract
NIR Laser application in bacteria is often focused on
mortality and antibiotic efficacy. The literature records on this point are absolutely diverse from mortality in different degrees to immortality and even viability enhancement. The aim of this study is to investigate 808 nm laser effects on
E.coli-DH5α viability and Growth with CFU, MTT and FCM assays. To obtain the purpose, bacteria in LB media put on with 808nm laser on 100 and 200 J/cm
2 dosages and were investigated and compared by CFU, MTT and FCM assay. CFU assay results after 24 hours incubation were not significantly different between laser treatments and control. (P=0.06). In contrast, MTT assay results after 1 hours from laser treatment indicated significant deleterious effects in 200 J/cm
2 laser treatment compared with control(P=0.006). On the other hand, FCM assay results of laser treatments with using of PI and Triton X100 not only approved MTT assay results but also revealed some dose dependent changes on bacteria ranging from increase membrane permeability to lethal damages. As a conclusion of the results in these method assays, we can state that these different laser doses produce diverse effects on viability and growth in
E.coli-DH5α. Consequently the laser treatments could be planned for antibiotic purposes or enhancing gene transformation process.
Atefeh Piran Zaei, Mehdi Dadmehr, Nad Ali Babaeian Jlodar, Nadali Bagheri, Seyed Morteza Hosseini,
Volume 12, Issue 1 (12-2020)
Abstract
DNA methylation detection by a novel fluorimetric nanobiosensor for early cancer diagnosis Quantum dots as a fluorescent probe are applied for cell biology, DNA transformation, biomedical imaging and cancer therapy. Biological based synthesis of nanoparticles would be more efficient and environment friendly rather than chemical approaches. In the present study, quantum dots have been synthesized through leaf methanolic extracts. The obtained results by UV-vis spectroscopy, TEM, FT-IR and fluorescence spectroscopy showed the presence of synthesized CdS quantum dots. Yellow and orange colors of obtained solution was also indicated the successful synthesis of CdS quantum dots. The maximum UV-Vis spectrum absorption of quantum dots was observed at 410 nm. Results of fluorescence analysis also showed that emission bands were at 475, 490 and 675 respectively which indicated the synthesis of different CdS quantum dots in different pH values. Obtained nanoparticle were spherical and at the range between 2-10 nm according to TEM analysis. FT-IR analysis also showed that the proteins, leucine and lysine amino acids, phenols and other functional groups present in physalis extracts would be determining factors for reducing CdS ions and converting them to quantum dots.
Hamidreza Farzin, Amiri Mohadese, Samira Kadoughani Sani, Majid Jamshidian Mojaver,
Volume 12, Issue 1 (12-2020)
Abstract
Abstract
Urinary tract infection is one of the most common and common bacterial infections, accounting for a significant proportion of hospital admissions (about 30-40%). Silver nanoparticles work by releasing silver ions against various bacteria. The fact that bacteria are not resistant to nanoparticles is very important and therefore will affect a wide range of bacteria.
Materials and Methods
In this study, 50 specimens of positive cultures with urinary tract infection referred to Imam Reza Hospital Laboratory in Bojnourd were studied. Resistance and susceptibility of the isolates were determined by disk diffusion method. In this study, antibacterial effects of silver nanoparticles were investigated by microdilution method using aqueous extract of Ganoderma leucidum. Vegetative electron microscopy was used to measure the size and shape of silver nanoparticles. In addition, infrared spectroscopy analysis was performed to investigate possible organic compounds involved in the synthesis of nanoparticles.
Results: The highest antibiotic resistance was related to ampicillin (84%). The resulting nanoparticles were 20 to 45 nm in size.
Conclusion:
The produced nanoparticles have antimicrobial activity and can be a good alternative in the treatment of antibiotic resistant infectious diseases.
Babak Sadeghi, Bite Koupaei,
Volume 12, Issue 2 (1-2022)
Abstract
In the present work, we describe the synthesis of silver nanoparticles (Ag-NPs) using seed aqueous extract of Psidium guajava (PG) and its antibacterial activity. UV–visible spectroscopy, X-ray diffraction (XRD), Fourier transform infra red spectroscopy (FTIR), transmission electron microscopy (TEM), scanning electron microscopy (SEM), and X-ray energy dispersive spectrophotometer (EDAX) were performed to ascertain the formation of Ag-NPs. It was observed that the growths of Ag-NPs are stopped within 35 min of reaction time. The synthesized Ag-NPs were characterized by a peak at 446 nm in the UV–visible spectrum. XRD confirmed the crystalline nature of the nanoparticles of 10-20 nm size. The XRD peaks at 38◦, 44◦, 64◦ and 77◦ can be indexed to the (1 1 1), (2 0 0), (2 2 0) and (3 1 1) Bragg’s reflections of cubic structure of metallic silver, respectively. The FTIR result clearly showed that the extracts containing OH as a functional group act in capping the nanoparticles synthesis. Antibacterial activities of Ag-NPs were tested against the growth of Gram-positive (S. aureus) using SEM. The inhibition was observed in the Ag-NPs against S. aureus. The results suggest that the synthesized Ag-NPs act as an effective antibacterial agent. It is confirmed that Ag-NPs are capable of rendering high antibacterial efficacy and hence has a great potential in the preparation of used drugs against bacterial diseases. The results confirmed that the (PG) is a very good eco friendly and nontoxic source for the synthesis of Ag-NPs as compared to the conventional chemical/physical methods.
