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A novel approach towards dethioacetalization reactions with H_2O_2-SOC1_2 system

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Chinese Chemical Letters 2012年第1期23卷 81-85页

作者： Kiumars Bahrami mohammad mehdi khodaei Maryam Tajik Vida Shakibaian Department of Organic Chemistry Faculty of ChemistryRazi UniversityKermanshah 67149-67346Iran Nanoscience and Nanotechnology Research Center(NNRC) Razi UniversityKermanshah 67149-67346Iran

A simple and efficient protocol for the deprotection of dithioacetal,1,3-dithianes and 1,3-dithiolanes has been developed using H_2O_2-SOC1_2 reagent *** addition to the absence of overoxidation products for oxidation-prone substrates,high chemoselectivity, the low cost and availability of the reagents,simplicity of the method,short reaction times,and excellent yields can also be considered as strong points for this method.

关键词： Deprotection Carbonyl protecting group Dethioacetalization Dithioacetals Hydrogen peroxide

The efficient synthesis of 14-alkyl or aryl 14H-dibenzo[a,j] xanthenes catalyzed by bismuth(Ⅲ)chloride under solvent-free conditions

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Chinese Chemical Letters 2011年第8期22卷 927-930页

作者： Ebrahim Soleimani mohammad mehdi khodaei Afsaneh Taheri Kal Koshvandi Department of Chemistry Razi UniversityKermanshah 67149Iran

An efficient method for the synthesis of 14-alkyl or aryl 14H-dibenzo[a,j]xanthene derivatives by the reaction of β-naphthol,and aldehydes in the presence of a catalytic amount of bismuth（Ⅲ） chloride（BiCl_3） under solvent-free conditions at 110℃is *** and aromatic aldehydes were used in the reaction and in all cases the desired products were synthesized *** reaction was studied under different temperatures;the maximum yield was obtained in a short reaction period at 110℃.The method offers the advantages of high yields,short reaction times,simplicity and easy workup compared to the conventional method of syntheses.

关键词： Bismuth(Ⅲ) chloride 14H-Dibenzo[a j]xanthenes β-Naphthol

The Effect of Spironolactone Loading on the Properties of 3D-Printed Polycaprolactone/Gold Nanoparticles Composite Scaffolds for Myocardial Tissue Engineering

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Journal of Bionic Engineering 2024年第2期21卷 924-937页

作者： Sharareh Ghaziof Shahrokh Shojaei mehdi mehdikhani mohammad khodaei Milad Jafari Nodoushan Department of Biomedical Engineering Central Tehran BranchIslamic Azad UniversityTehran***Iran Stem Cells Research Center Tissue Engineering and Regenerative Medicine InstituteCentral Tehran BranchIslamic Azad UniversityTehran***Iran Department of Biomedical Engineering Faculty of EngineeringUniversity of IsfahanIsfahan***Iran Materials Engineering Group Golpayegan College of EngineeringIsfahan University of TechnologyGolpayegan87717-67498Iran Hard Tissue Engineering Research Center Tissue Engineering and Regenerative Medicine InstituteCentral Tehran BranchIslamic Azad UniversityTehran***Iran

Engineered cardiac constructs(ECC)aid in the progression of regenerative medicine,disease modeling and targeted drug delivery to adjust and aim the release of remedial combination as well as decrease the side effects of *** this research,polycaprolactone/gold nanoparticles(PCL/GNPs)three-dimensional(3D)composite scaffolds were manufactured by 3D printing using the fused deposition modeling(FDM)method and then coated with gelatin/spironolactone(GEL/SPL).Scanning electron microscopy(SEM)and Fourier transform-infrared spectroscopy(FTIR–ATR)were applied to characterize the ***,drug release,biodegradation,behavior of the myoblasts(H9C2)cell line,and cytotoxicity of the 3D scaffolds were *** microstructural observation of the scaffolds reported interconnected pores with 150–300µm in *** 3D scaffolds were degraded significantly after 28 days of immersion in stimulated body fluid(SBF),with the maximum rate of GEL-coated 3D *** release from cross-linked GEL coating demonstrated the excess of drug release over time,and according to the control release systems,the drug delivery systems(DDS)went into balance after the 14th *** addition,cell culture study showed that with the addition of GNPs,the proliferation of(H9C2)was enhanced,and with GEL/SPL coating the cell attachment and viability were improved *** findings suggested that PCL/GNPs 3D scaffolds coated with GEL/SPL can be an appropriate choice for myocardial tissue engineering.

关键词： Polycaprolactone Gold nanoparticles Drug delivery systems Spironolactone Cell behavior Myoblasts

Surface treatment of titanium dental implant with H2O2 solution

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International Journal of Minerals,Metallurgy and Materials 2020年第9期27卷 1281-1286页

作者： mohammad khodaei Kamran Amini Alireza Valanezhad Ikuya Watanabe Department of Materials Science and Engineering Golpayegan University of TechnologyGolpayegan ***Iran Center for Advanced Engineering Research Majlesi BranchIslamic Azad UniversityIsfahan 196151194Iran Department of Dental and Biomedical Materials Science Graduate School of Biomedical SciencesNagasaki University1-7-1 SakamotoNagasaki 852-8588Japan

The surface treatment is important for titanium and its alloys as promising candidates for dental implantation due to their bioinert *** surface samples were modified using H2O2 solution at different times up to 72 h to boost their *** to the results of the field emission scanning electron microscopy test,some nanostructures are formed on the surface of treated titanium samples and increased in size by increasing the time of treatment up to 24 *** 24 h of application,the sharpness of nanostructures decreased and the micro-cracks and discontinuity in the coating surface *** results of the X-ray diffraction study and Raman spectroscopy revealed that anatase(TiO2)was formed on the surface of treated titanium *** peak intensity of Raman spectroscopy increased with an improvement in treatment time of up to 24 h and then decreased due to the discontinuity of the *** wettability and ability to form apatite were reached at 6 h of *** is clear that the treatment time has a significant effect on the surface treatment of titanium using the H2O2 solution.

关键词： titanium implant surface treatment hydrogen peroxide anatase dental implant

Evaluation the Properties of Polycaprolactone/Fluorapatite Nano-biocomposite

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Journal of Bionic Engineering 2022年第1期19卷 179-187页

作者： Mojtaba Momeni Kamran Amini Ali Heidari mohammad khodaei Department of Mechanical Engineering Khomeinishahr BranchIslamic Azad UniversityKhomeinishahr84181-48499IsfahanIran Center for Advanced Engineering Research Majlesi BranchIslamic Azad University86316-56451IsfahanIran Materials Engineering Group Golpayegan College of EngineeringIsfahan University of Technology87717-67498GolpayeganIran

In this study,nano-biocomposites of polycaprolactone(PCL)as the matrix and different amounts of nanofluorapatite(nFA)(0,10,20 and 30 wt.%)as the reinforcement were prepared for possible scaffold fabrication using the fused filament fabrication(FFF)3D *** Emission Scanning Electron Microscopy(FE-SEM)and Energy Dispersive Spectroscopy(EDS)showed that nFA particles were well distributed in the PCL matrix.X-ray diffraction analysis(XRD)and Fourier Transform Infrared Spectroscopy(FTIR)depicted no chemical interaction between the elements of the *** Scanning Calorimetric(DSC)analysis was then used to assess the thermal properties of the composites,suggesting that this could be due to the amorphous phase formation of the intermolecular hydrogen bonds between PCL and nFA,resulting in the suppression of PCL *** results of mechanical characterization also showed that the addition of nFA up to 20 wt.%to the PCL increased the tensile and yield strength,as well as reducing the elongation at both yield and failure points and increasing the Young *** best mechanical properties were obtained for the PCL/20nFA *** strength and Young modulus were increased by 30%and 179%,respectively;meanwhile,elongation of PCL/20nFA was decreased by 70%,as compared to the naked *** changes could be attributed to the better distribution of the nFA filler in the PCL *** to the obtained results,PCL/20nFA could be regarded as a good composite in terms of the mechanical properties for the regeneration of the bone tissue.

关键词： Nano-biocomposite Polycaprolactone Fluorapatite Bone tissue engineering Mechanical properties

Fabrication and Characterization of Poly Lactic Acid Scaffolds by Fused Deposition Modeling for Bone Tissue Engineering

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Journal of Wuhan University of Technology(Materials Science) 2020年第1期35卷 248-251页

作者： mohammad khodaei Kamran Amini Alireza Valanezhad Department of Materials Science and Engineering Golpayegan University of TechnologyGolpayeganIran Department of Materials Engineering Tiran BranchIslamic Azad UniversityIsfahanIran Center for Advanced Engineering Research Majlesi BranchIslamic Azad UniversityIsfahanIran Department of Dental and Biomedical Materials Science Nagasaki UniversityNagasakiJapan

Three-dimensional porous poly-lactic acid(PLA) scaffold was fabricated using fused deposition modeling(FDM) method including 30%, 50% and 70% nominal porosity. Study of phases in initial polymeric material and printed scaffolds was done by X-ray diffraction(XRD), and no significant phase difference was observed due to the manufacturing process, and the poly-lactic acid retains its crystalline properties. The results of the mechanical properties evaluation by the compression test show that the mechanical properties of the scaffold have decreased significantly with increasing the porosity of scaffold. The microstructure of scaffolds were studied by scanning electron microscope(SEM), showing that the pores had a regular arrangement and their morphology changed with porosity change. The mechanical properties of the poly-lactic acid scaffolds printed using fused deposition modeling, can be adapted to the surrounding tissue, by porosity change.

关键词： 3D porous scaffold fused deposition modeling poly-lactic acid biodegradable polymer

Fabrication of Porous Mg-Zn Scaffold through Modified Replica Method for Bone Tissue Engineering

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Journal of Bionic Engineering 2018年第5期15卷 907-913页

作者： Amir Hamed Aghajanian Bijan Abbasi Khazaei mohammad khodaei mohammad Rafienia Department of Materials Engineering Faculty of Engineering Razi University Kermanshah Iran Dental Research Center School of Dentistry Isfahan University of Medical Sciences Isfahan 81746-73461 Iran Biosensor Research Center lsfahan University of Medical Sciences Isfahan 81744176 Iran

Biodegradable scaffolds are essential parts in hard tissue engineering. A highly porous magnesium-zinc （Mg-Zn 4 wt.%） scaffold with different Mg-Zn powder to liquid media ratios （50 wt.%, 70 wt.% and 90 wt.%） and different concentrations of ethanol （0 vol.%, 10 vol.%, 20 vol.% and 40 vol.%） were prepared through modified replica method. The mechanical properties were assessed through compression test and the structures of scaffolds were examined by Scanning Electron Microscope （SEM）. Results show that, the increase in Mg-Zn powder to liquid media ratio （50 wt.% to 90 wt.%） in ethanol free slurry, increases the thickness of struts （37 lam to 74 lam） and the plateau stress （0.5 MPa to 1.4 MPa）. The results obtained from X-ray Diffractometry （XRD） and compression test indicate that consuming ethanol in liquid media of replica, results in higher plateau stress by 46% due to less Mg-water reaction and no formation of Mg（OH）2 in the scaffold. The results of porosity measurement indicate that water-ethanol mixture composition and different solid fractions have no significant effects on true and apparent porosities of the fabricated scaffolds.

关键词： porous magnesium scaffold replica method Mg-Zn powder to water ratio mechanical properties

Effect of Oxidizing Atmosphere on the Surface of Titanium Dental Implant Material

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Journal of Bionic Engineering 2019年第6期16卷 1052-1060页

作者： mohammad khodaei Akram Alizadeh Hamid Reza Madaah Hosseini Department of Materials Science and Engineering Golpayegan University of TechnologyGolpayegan 87717-65651Iran Department of Tissue Engineering School of Advanced TechnologiesShahrekord University of Medical SciencesShahrekord 88157-13471Iran Department of Materials Science and Engineering Sharif University of TechnologyTehran 14588-89694Iran

Direct oxidation is a simple and effective method for titanium surface *** this research,a titanium sample was directly oxidized at the high temperature in two different atmospheres,air and pure oxygen,to obtain better atmosphere for titanium surface *** results of the Raman spectroscopy indicated that in both atmospheres,the rutile bioactive phase(TiO2)has been formed on the titanium *** results of X-ray diffraction(XRD)also revealed that the surface of oxygen-treated sample was composed of the rutile phase and titanium monoxide(TiO),while at the surface of the air-treated sample,the rutile phase and titanium dioxide had been ***,the results of Field Emission Scanning Electron Microscopy(FE-SEM)showed that by the surface treatment of titanium in both atmospheres,some micro-features including cracks thinner than 30 nm were formed on the *** of more apatite forming ability and fewer water contact angle and more L-929 cell attachment of the air-treated titanium,it seemed that air,in comparison to the pure oxygen,is more promising atmosphere for the direct oxidation of titanium and improving its biofunctionalization.

关键词： titanium implant surface treatment direct oxidation anatase rutile biomedical-materials

Magnesium/Nano-hydroxyapatite Composite for Bone Reconstruction: The Effect of Processing Method

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Journal of Bionic Engineering 2020年第1期17卷 92-99页

作者： mohammad khodaei Farahnaz Nejatidanesh mohammad Javad Shirani Srinivasan Iyengar Hossein Sina Omid Savabi Department of Materials Science and Engineering Golpayegan University of TechnologyGolpayegan ***Iran Dental Materials Research Center Dental Research InstituteSchool of DentistryIsfahan University of Medical SciencesIsfahan ***Iran Post graduate student of Prosthodontics Student Research CommitteeSchool of DentistryIsfahan University of Medical SciencesIsfahan ***Iran Materials Engineering Division Faculty of EngineeringLund UniversityLund 11822100Sweden European Spallation Source ERIC Lund 17622100Sweden Dental Research Center Dental Research InstituteSchool of DentistryIsfahan University of Medical SciencesIsfahan ***Iran

Nano-ceramic particles can serve as reinforcing agents for metallic materials to improve their mechanical ***,it is important to ensure chemical compatibility between the matrix and *** the present study,magnesium composites with and without nano-hydroxyapatite(nHA)particles were fabricated for bone reconstruction *** different techniques were used,Conventional Sintering(CS)of powder compacts and Spark Plasma Sintering(SPS)of pre-compacted *** showed that a 10 wt%addition of nHA particles to magnesium,followed by SPS improved the compression strength by 27%.CS did not lead to any significant improvement compared to SPS processing.X-ray diffraction data after CS revealed the formation of unfavorable phases due to chemical reactions between nHA particles and the magnesium matrix,while these phases were absent after SPS *** mechanical properties of the specimens fabricated by CS were much inferior to those processed using *** shorter processing time associated with SPS leaded to reduced interaction between nHA particles and the Mg-matrix,compared to CS.

关键词： magnesium nano-hydroxyapatite composite materials in situ reaction biomedical-materials