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Biomarkers can be ideal indicators for assessing the risk of the presence of a disease. In this study, a label-free electrochemical biosensor was designed to quantify the vascular endothelial growth factor A (165) (VEGF-A(165)) antigen, using reduced graphene oxide-gold nanoparticle for early detection of breast cancer. The conductivity of gold nanoparticle along with its biocompatibility provide an enhanced surface, suitable for anti-VEGF antibody immobilization. 11-mercaptoundecanoic acid was used to facilitate a single-step and convenient bonding of the antibodies to the surface, compared to previous studies. The dynamic range of the biosensor was between 20 to 120 pg/ml and its limit of detection of the biomarker VEGF-A(165) was obtained to be about 0.007 pg/ml, using different electric signal transduction modes. Hence, the biosensor is a beneficial immunosensor with high sensitivity and ideal dynamic range for early-stage diagnosis of breast cancer and other cancers diseases associated with expression of VEGF-A(165). The as-prepared immunosensor could be efficiently employed for designing a point-of-care diagnostic platform.

The behaviour of semiconducting graphene quantum dots (GQDs), as good candidates for various biological carrier applications and optical sensing, are necessary to be studied under various conditions. In this study, GQD models were generated according to the geometrical and chemical specifications of synthesized GQDs to achieve the most realistic models. The GQDs’ bandgap and distribution of their electric surface charges were obtained using computational chemistry method. Finite element analysis was conducted on pristine and defective GQDs to study Young and shear modulus. Buckling load and resonant frequency modes of GQDs were calculated analytically and demonstrated under various boundary conditions. The dimension of GQDs has an average of 3.5 ± 0.4 nm, with an interlayer spacing of 0.36–0.40 nm. Computational chemistry studies revealed the characteristic zero-band-gap nature of graphene. Finite element studies showed that the by introducing the inevitable dislocation, mono atom vacancy and Stone–Wales defects to GQD models, their mechanical properties reduces to approach data from experimental investigations, whereas an increase in the number of layers does not influence the obtained results significantly.

Polyaniline/perlite-barium ferrite nanoparticles (PANI/PBF-NPs) composite electrodes were studied in here for super capacitor applications. The PBF-NPs synthesized using hydrothermal technique and then the composite electrode was fabricated electrochemically by cyclic voltammetry (CV) technique. Transmission electron microscopy (TEM), Scanning electron microscopy (SEM), X-ray diffraction (XRD), Brunauer-Emmett-Teller nitrogen adsorption/desorption (BET) and fast Fourier transform infrared spectroscopy (FTIR) were employed to study the morphological and structural properties of the prepared electrodes. Furthermore, various electrochemical techniques were used such as CV, Galvano static charge-discharge (GCD) and electrochemical impedance spectroscopy (EIS) to investigate their electrochemical performance as well. SEM graphs show uniform distribution of 60-nm PBF-NPs in the PANI filaments. The specific capacitance of PANI and composite electrodes was obtained to be 225 and 330 F/g, respectively. In addition, inclusion of PBF-NPs in the structure of PANI electrode had significantly increased the conductivity of composite electrodes. Continuous charge-discharge cycles test illustrated the good capability of this nano composite material for use as a charge storage device.

Currently, Coronavirus disease (COVID-19), which is caused by SARS-COV2, has infected over 117.7 million people. Even considering that the critical cases are below 1%, there will be still a large number of populations who might receive rapid medical attention to control infection. Therefore, a huge part of the population including elderly people and active cases needs emergency antiviral drugs. Unique structural aspects and specificity of the main protease (Mpro) have made it among the best inhibitory targets to develop chemotherapeutics in combating the pandemic. Here, the biophysical chemistry of ligand-protein complex formation and properties of some of the front-line inhibitors are explored and discussed.

Direct pyrolysis of citric acid (CA) has been proved to be a facile bottom–up technique for making pristine carbon dots (CD) with homogenous size distribution. However, limited reports are available on systematic optimization of carbonization degree. In this investigation, pyrolysis temperatures between 160 °C and 220 °C were studied, based on CA thermal decomposition path, using various heating durations. The effect of the formation of more carbonized carbon particles (MCCPs), as the major byproduct of this method, on photoluminescence properties of CDs was also considered. The NaOH amount that neutralizes the solution and the effect of dilution on the emission intensity, were introduced as simple and accessible factors for monitoring carbonization degree, and an estimate of MCCP/CD ratio, respectively. The results show that the CDs fabricated at 160 °C, 50 minutes attain almost twice higher quantum yield (QY) of 29% than highest QY reported based on pyrolysis of CA. The so–prepared CDs can be employed as excellent candidates for turn–off sensing. As a proof of concept, detection limit of 50 nM for Hg2+ was achieved using a facile and inexpensive smartphone set–up that is able to quantify and compare fluorescent intensity in several samples simultaneously.

Separation of tumor cells is a promising approach that helps not only in early detection of cancer but also as an efficient tool that holds great importance in prohibiting cancer cell mutation, drug resistance to treatments, and in granting successful adjuvant therapies. As one of the highly efficient processes for the separation of single cells, tumor cells, and specific proteins from fresh whole blood, a magnetic iron oxide nanoparticle (IONP)-based immunomagnetic separation technique has been developed in this article. The synthesized IONPs were modified with antibodies (Abs) against human epithelial growth factor receptor 2 (HER2), which is overexpressed and/or amplified in about 15% of breast cancer patients with several types of human cancer cells. The prepared Ab-conjugated IONPs (Ab-IONPs) attach HER2-positive cancer cells exclusively and can serve as specific high-efficient single-cell separation agents. The results showed that the magnetic IONPs have been successfully attached to the Abs via 1-ethyl-3-(3-dimethylaminopropyl) carbodiimide/N-hydroxysuccinimide linkers. Maximum targeting efficiency of the Ab-IONP complex, which was 94.5 ± 0.8% for BT474 and 70.6 ± 0.4% for mixture of cells (BT474 and MCF7), was achieved with a minimum amount of Abs, to provide an economically efficient single-cell detection device.

Graphene quantum dots (GQDs) are known as emerging sub-10 nm nanoparticles (NPs), which are in fact few-layered pieces of graphene, capable of emitting blue fluorescence, when exposed to 360 nm UV light. Understanding the details of the interaction between GQDs and lipase can serve as a critical step for improving the biological outcome of GQD-derived drug-delivery and diagnosis systems. The interaction occurs in the form of surface adsorption, which can subsequently influence the physicochemical properties of both the NP and the protein. Hence, a systematic approach was taken here to optimize the GQDs' synthesis conditions in order to achieve the highest possible quantum yield (QY). Furthermore, to understands the influence of the interaction of GQDs and lipase, on both the activity of lipase and the emission intensity of GQDs, various incubation conditions were tested to achieve optimized conditions over central composite design algorithm by Design-Expert®, using response surface methodology. The results show that the GQDs fabricated by thermal decomposition of citric acid at 160°C, with a heating duration of 55 min, obtain almost three times higher QY than the highest values reported previously. The best enzymatic activity after the formation of the hard corona, as well as the highest fluorescent emission, were achieved at GQD-to-enzyme ratios within the rage of 23-25%, at temperatures between 41 and 42°C, for 6-8 min. In the aforementioned condition, the enzyme retains 91-95% of its activity and the NP preserves about 80-82% of its fluorescence intensity after incubation.

There has been an outburst of attraction in the use of nanoparticles and nanomaterials for bioimaging, biosensing and other chemical and biological applications. At the leading edge of the new trend of the emerging nanoparticles in the carbonic nanomaterials family, fluorescent carbon quantum dots have drawn considerable attention due to their unique and tunable properties. In this chapter, an overview of the fundamental properties of carbon quantum dots is provided first. Then, it focuses majorly on the in-vivo and in-vitro bioimaging, biosensing, drug delivery, wound-dressing and photocatalysis applications of the nanomaterial. This chapter is expected to offer beneficial insight into the role of carbon quantum dots in biological applications and encourage more exploration on the topic.

Background Drug delivery system (DDS) is one of the most recent strategies to enhance specific targeting of tumor cells in cancer treatment. The major goal in DDS is to achieve higher accumulation of the drug in the tumor tissue and hence to reduce systemic toxicity and side effects of chemotherapeutic agents. Objective To meet these challenges in breast cancer treatment, specific targeting of the human epidermal growth factor receptor-2 (HER2) on the surface of tumor cells is needed, which is possible by means of HER2 monoclonal antibody (mAb). Methods Therefore, in this study, gemcitabine (Gem)-loaded nanoparticles (NP) based on bovine serum albumin (BSA) were produced by desolvation method and then, they were targeted by the conjugation of HER2 mAb through cross linkers. The produced agents were used for targeting of HER2 overexpressing in breast cancer cells. The agents were characterized for particle size, zeta potential, morphology, drug-loading efficiency, mAb conjugation efficiency and investigated on MCF7 and BT474 breast cancer cell lines afterwards. Results The size and surface charge of targeted drug-loaded NPs were obtained to be 208.9 ± 10 nm and −19.1 ± 2.1 mV, respectively. In addition, they were observed to have a smooth spherical shape. The designed targeted DDS showed an enhanced accumulation of the drug and subsequently higher cell-death rate in HER2-positive breast cancer cells, in comparison with non-targeted drug-loaded NPs, BSA NPs and free drug. Conclusion Thus, it is found that BSA NPs with the efficient conjugation of mAb and loading of Gem can make a promising carrier for cancer treatment.

A novel mixed matrix nanofiltration membrane was developed by blending carbon dots (CDs) into a polyethersulfone (PES) matrix. The resulted membranes were characterized using scanning electron microscopy (SEM), atomic force microscopy (AFM), attenuated total reflection (ATR), zeta potential, tensile strength, overall porosity, and water contact angle tests. Pure water flux, antifouling, as well as salt and dye rejection properties were also studied. Fouling resistance of the prepared nanocomposite membranes was tested with filtration of a bovine serum albumin (BSA) solution. The calculated roughness parameters showed that addition of CDs can effectively reduce the roughness value of the PES membrane. The membrane permeability raised to the maximum value of 76.5 kg/m2 h, which is almost twice the bare PES, by step-wise increasing of the CDs dosage from 0.05 to 0.50 wt%. The 0.50 wt% PES/CDs membrane also showed significant antifouling properties, with the total and irreversible fouling values of 35.6 and 20.3%, respectively, compared to the values of 54.7 and 46.3%, in case of the bare PES. Salt rejection was remarkably improved after addition of CDs with the sequence of Na2SO4 > MgSO4 > NaCl, after 90 min of filtration. The dye rejection was near total removal with above 97% in all prepared membranes, where the maximum dye removal efficiency (98.9%) was observed for the 0.50 wt% PES/CDs, introducing CDs as an excellent membrane modifier for wastewater treatment applications.

This paper studies the effect of three different types of defects on the Young’s modulus of zigzag and armchair single-walled carbon nanotubes. The defects are randomly introduced into the structure with a maximum distribution density of 2%. The defects include monovacancies, before and after reconstruction of dangling bonds, resulting finally to the Stone-Wales defect. As the length of model effects computation time significantly, finite element models are created in pristine and very short tube lengths to investigate the effect of model length on the results obtained. The investigation shows that the introduction of defects generally weakens the elastic strength of tubes but to rather different degrees. However, the structure is capable of restoring its elastic strength by rearranging its atoms in form of the Stone-Wales defect. The use of shorter nanotube models on the other hand can lead to accurate results if appropriate cylindrical boundary conditions are defined.

The finite element method was applied to determine the most appropriate method for the determination of the shear modulus of single- and multi-walled carbon nanotubes. The shear modulus can be determined directly from torsion tests or for isotropic materials based on the values of Young’s modulus and Poisson’s ratio. However, if the material is anisotropic, the shear modulus is an independent material property and cannot be determined based on two other elastic parameters. To clarify the most appropriate approach, the shear modulus of carbon nanotubes was obtained through simulation of two basic tests. First, the modulus was directly calculated from torsion tests. Second, a tensile test was simulated and the corresponding Young’s modulus and Poisson’s ratio were calculated and the shear modulus of the models was obtained by the relationship based on Young’s modulus and Poisson’s ratio. The comparison of both methods revealed that carbon nanotubes behave rather as an anisotropic material. The involved error based on the isotropy assumption was quantified for different configurations, number of cell walls and under the influence of imperfections.

Finite element method has been employed in numerical analysis of a wide variety of hetero-junction types in carbon nanotubes with different chiralities and configurations. The investigation does not only include perfect CNTs, but in various studies, several atomic defects, for example, silicon impurities and vacant sites, were introduced to some of the hetero-junction models as well. Therefore, details on the techniques employed for studying the effect of perfect and defective hetero-junction carbon nanotubes on the major mechanical properties is of significant importance. The properties include tensile, torsion, and buckling tests and the influence of the atomic defects on the Young's modulus of hetero-junction carbon nanotubes, numerically. Based on the available results from different mechanical tests on homogeneous tubes, an increase in the diameter of the homogeneous nanotubes of the same length leads to a slight decrease in the shear modulus and vice versa, an increase in the critical buckling loads. However, the Young's modulus of these models remained nearly the same for tubes of the same chiralities. It was also discovered that armchair and zigzag carbon nanotubes had the highest Young's and shear moduli, respectively. The evaluation of the mechanical properties of the hetero-junction carbon nanotubes revealed that the size of their hetero-connection and the diameter of their fundamental tubes significantly dominate their mechanical properties. It was clearly observed that hetero-junction carbon nanotubes had lower tensile stiffness than their corresponding fundamental tubes. However, their shear modulus and critical buckling load lay in the range of the corresponding quantities for their fundamental homogeneous tubes, generally closer to the shear modulus and critical buckling load of their corresponding fundamental thinner tubes. Furthermore, the results from the mechanical tests demonstrated that hetero-junction carbon nanotubes with armchair-armchair and zigzag-zigzag connections have the highest Young's modulus while the shear modulus and critical buckling load peaks were observed in zigzag-zigzag and armchair-armchair hetero-junction models, respectively. Hetero-junction carbon nanotubes with armchair-zigzag kinks also revealed to have the most fragile mechanical properties among the models. Comparison between the obtained moduli and buckling loads of perfect and atomically defective hetero-junction carbon nanotubes clearly illustrated that the atomic defects in the structure of hetero-junction carbon nanotubes cause a linear decline in their mechanical properties, which can be expressed by mathematical relations, in terms of the amount of such defects for the prediction of the mechanical properties of the atomically defective hetero-junction carbon nanotubes.

Today, many fields of rapidly growing research about nanomaterials and nanodevices are dependent on a combined detailed investigation between nanoscience and engineering. Hence, current nanotechnological engineering requires a vital linkage between fundamental research about the nature of the materials, which should be sought in nanoscience, and engineering investigation tools through simulations and modeling in computational nanomechanics. This linkage is necessary to obtain a comprehensive picture of the properties and characteristics of the studied nanomaterials and nanodevices under various conditions. In this chapter, a review of the fundamental concepts of the Newtonian mechanics, including Lagrangian and Hamiltonian functions is provided first. The developed equations of motion of a system with interacting material points are introduced then. After that, based on the physics of nanosystems, which can be applicable in any material phases, basic concepts of molecular dynamic simulations are introduced. Some interatomic potentials from which Morse function is recognized as an accurate definition are discussed in the next step for defining the natural bond length. With the purpose of decreasing computational effort, the cut-off radius is considered to limit atomic interactions to immediate neighbors only. The link between molecular dynamics and quantum mechanics is then explained using a simple classical example of two interacting hydrogen atoms, and the major limitations of the simulation method are discussed. Length and timescale limitation of molecular dynamics simulation technique are the major reasons behind opting multiscale simulations rather than molecular dynamics, which are explained briefly at the final sections of this chapter.

Finite element models of single-walled and multi-walled carbon nanotubes in their perfect and fundamental forms (zigzag and armchair) were constructed. Then, after obtaining the mechanical properties of perfect carbon nanotubes, three types of imperfections, i.e., doping with Si atoms, carbon vacancy and perturbation of the ideal location of the carbon atom were introduced in different amounts to the perfect models to make them imperfect. Finally, the mechanical properties of the imperfect carbon nanotubes were numerically simulated and compared with those of perfect ones. Simple relations which predict the change of Young’s modulus as a function of the imperfection percentage were derived. The results show that the existence of any kind of imperfection in the perfect models leads to lower stiffness values. This study allows to realistically judge any simulation based on perfect structures and gives for the first time a good estimate to which extend the values based on perfect structures must be lowered in order to account for common imperfections to predict the mechanical properties of carbon nanotubes which are nowadays used in the production of advanced nanocomposites and reinforced materials.

This paper studies the extent to which the effective stiffness of composite materials can be impacted by the characteristic waviness of nanotubes embedded in polymers. A three-dimensional finite element model is used to investigate the effect of volume fraction and waviness on mechanical properties, i.e. Young’s modulus and Poisson’s ratio, of composites reinforced with waved carbon nanotubes. According to the obtained results, the nanotube waviness causes a decrease in the longitudinal and transverse Young’s modulus of composites, compared to the straight nanotube reinforcement, but the change in the value of transverse Young’s modulus ( Eyy) is less remarkable than the longitudinal Young’s modulus ( Exx). Furthermore, the effect of fiber curvature on Poisson’s ratio has also been studied. The results show that the curvature has not much effect on Poisson’s ratio and when a fiber curvature changes, Poisson’s ratio value almost remains unchanged. In addition, the effect of fiber volume fraction on the longitudinal Young’s modulus and major Poisson’s ratio has been studied. As the mesh density may have a significant role in evaluating the model, several different meshes have been generated in order to predict their effect on the mechanical properties of the composite.

In this study, single-walled carbon nanotubes were generated in their perfect state as finite element models in the MSC.Marc software. The buckling behaviour and resonant frequency modes of the two limiting cases of carbon nanotubes, i.e. the armchair and zigzag models, were studied. The obtained results were compared with the classical analytical solutions related to a similar continuum structure of a hollow cylinder. The buckling behaviour of single-walled carbon nanotubes under cantilever boundary conditions proved to be almost identical to the prediction of the classical Euler equation. Furthermore, there was very good agreement between the analytical and finite element results of the studied single-walled carbon nanotubes; though the achieved value of the first mode of frequency, obtained from the finite element results, was more accurate than the higher modes.

Having extremely high stiffness and low specific weight, carbon nanotubes (CNTs) have been known recently as perfect reinforcing fibers in nanotechnology. They can improve the stiffness and strength of nanocomposites by being used as reinforcing elements for example in polymer matrices. The corresponding properties of the fibers and matrix, such as volume fraction and aspect ratio are some of the significant factors in the characterization of mechanical properties of CNT reinforced composites. In recent years, the way in which fibers are distributed inside the matrix, in terms of randomness, has introduced another important factor in characterizing the mechanical properties of such composites. Based on this factor, composites can be classified into two types namely, aligned and randomly distributed. This research has studied the effect of random distribution of fibers in the matrix on the elastic modulus and initial yield stress of the nanocomposite. Therefore, several models of composites, with different distribution of fibers, were considered while holding the volume fractions and aspect ratio constant. As a result, the effect of randomness on the effective modulus of CNT reinforced composites was estimated. The finite element method (FEM), using the MSC.Marc software, was employed to predict the effective modulus of CNT reinforced composites and the results were successfully validated by comparison with the analytical Halpin–Tsai method.

In this study, a finite element model of a representative volume element that contains a hollow and filled single-walled Carbon nanotube (SWCNT) in two case studies was generated. It was assumed that the nanocomposites have geometric periodicity with respect to local length scale and the elastic properties can be represented by those of the representative volume element (RVE). Elastic properties in agreement with existing literature values for the Carbon nanotube and the matrix were assigned. Then for the two case studies, the tensile test was simulated to find the effect of the geometry, i.e. the volume fraction of matrix and SWCNT's properties variation, on the effective Young's modulus of the structure. In another approach, by applying perpendicular loading to the tube direction, the effect of matrix volume fraction on the transverse Young's modulus was studied. The investigations showed that for both RVEs with filled SWCNT and hollow SWCNT, the effective Young's modulus of the structure decreases approximately linear as the matrix volume fraction increases. The value of Young's modulus of the RVE with a filled Carbon nanotube was obtained to be higher than the RVE with the hollow Carbon nanotube. In addition, by increasing the tube diameter, the effective Young's modulus of the structure increases and the transverse Young's modulus decreases approximately linear for filled tubes but this parameter remains rather constant in the case of the hollow tube by increasing the matrix volume fraction.

In This study, finite element models of Single-Walled Carbon Nanotube (SWCNT) in their perfect form were generated. Then, after deriving mechanical properties in agreement with existing literature values, different levels of perturbation and missing atoms in the structure were applied. In another approach, some of the Carbon atoms were replaced with Silicon to produce a Si-doped SWCNT. Mechanical properties of the three kinds of imperfect structures of SWCNT were then compared with the perfect structure results, for both fundamental Carbon Nanotubes, namely Zigzag and Armchair.The results show that with any kind of imperfection, the stiffness of the structure decreases compared to the perfect SWCNT.

High-density structures with well-ordered nanohole arrays have been obtained by the self-ordering growth of nanopores using 25?40?V anodization voltages in a sulfuric?oxalic acid mixture. In each anodization voltage, two types of electrolyte mixture were used with low and high sulfuric concentrations at a constant pH value. The ordering and regularity of a nanohole array was quantified by analysis of fast Fourier transformations of scanning electron and atomic force microscope images. The results show that the long range ordering of nanohole array is superior for high sulfuric concentration, while regularity is more pronounced for low sulfuric concentration. The interpore distance in the oxalic?sulfuric mixture is higher in the case of low sulfuric concentration. It is almost proportional to 2.6?nm?V?1 and 2.5?nm?V?1 for the electrolyte mixture with low and high sulfuric concentrations, respectively. While the porosity is nearly 10% for samples made in standard sulfuric and oxalic acid using 25?V and 40?V anodization voltage, respectively, it increases up to 50% for the sample made with 37.5?V in an oxalic?sulfuric mixture.

The use of fiber reinforced polymer composites (FRPs) is enhancing in different engineering applications because of their high specific strength and stiffness.

As one of the major classes of polymeric materials, various types of epoxies are used extensively in different engineering applications such as automotive and electronic industries. Epoxy-based composite materials have become proper substitutes for traditional materials like metals, metal alloys, wood, etc. due to their prominent properties such as lightness, ease of processing and relatively low cost. However, one of the major drawbacks in their increasing applications is their poor surface properties.

There are limited studies which have extracted global equations for calculation of Young's modulus (E) in both pristine and defective carbon nanotubes (CNT), especially when a combination of different defects such as atom-vacancy and-misplacement exist simultaneously in the studied CNT. In this study, the finite element method was used to investigate E for a large set of perfect and defective single walled carbon nanotubes (2440 finite element models), including armchair, zigzag and chiral tubes. The obtained results were then employed as the basis for achieving accurate global equations for calculation of E in perfect and defective carbon nanotubes at various defect percentages. Despite most previous studies, which were based on the tube's diameter, the chiral indices (n, m) have been considered here as variables to predict the stiffness of carbon nanotubes. The achieved equations showed to be accurate, with maximum errors below 2% and 10% for perfect and defective tubes, respectively, compared to FE results. Based on the obtained equations, a computer execution file was developed which is capable of calculating E when different percentages of defects are introduced to the structure. The results show that unlike single defect states, the existence of any combination of atom vacancy and atom misplacement defects causes dramatic reduction in the stiffness of carbon nanotubes. Furthermore, the role of vacancy defects in the reduction of tube's elastic properties revealed to be more significant than misplacement defects. The results not only demonstrate that edge defects influence Young's modulus more noticeably, but also confirm previous works showing that armchair edged structures are less vulnerable to defects, as compared to zigzag.

In this study, Single-Walled and Multi-Walled Carbon Nanotubes in their perfect forms were investigated by the Finite Element Method. Details on the modeling of the structure are provided in this paper, including the appropriate elements, the element properties that should be defined based on the atomic structure of Carbon Nanotubes and the corresponding chemical bonds. Non-covalent van der Waals interactions between two neighbor atoms as well as the required approximations for the modeling of the structures with this kind of interaction are also presented. Specific attention was dedicated to the necessity of using some time- and energy-consuming steps in the simulation process. First, the effect of simulating only a single ring of the whole structure is studied to find out if it would represent the same mechanical behavior as the long structure. Results show that by applying an appropriate set of boundary conditions, the stiffness of the shortened structure is practically equal to the long perfect structure. Furthermore, Multi-Walled Carbon Nanotube structures with and without defining the van der Waals force are studied. Based on the observations, applying the van der Waals force does not significantly influence the obtained Young's modulus of the structure in the case of a uniaxial tensile test.

The paper presents an effective algorithm to analyze MR-images in order to recognize Alzheimer's disease (AD) which appeared in patient's brain. The features of interest are categorized in features of the spatial domain (FSD's) and Features of the frequency domain (FFD's) which are based on the first four statistic moments of the wavelet transform. Extracted features have been classified by a multi-layer perceptron artificial neural network (ANN). Before ANN, the number of features is reduced from 44 to 12 to optimize and eliminate any correlation between them. The contribution of this paper is to demonstrate that by using the wavelet transform number of features needed for AD diagnosis has been reduced in comparison with the previous work. We achieved 79% and 100% accuracy among test set and training set respectively, including 93 MR-images.