Publications by authors named "Rahmatollah Rahimi"

16 Publications

  • Page 1 of 1

Antibacterial Photoactivity and Thermal Stability of Tetra-cationic Porphyrins Immobilized on Cellulosic Fabrics.

Photochem Photobiol 2021 Mar 29;97(2):385-397. Epub 2020 Nov 29.

Bioinorganic Chemistry Laboratory, Department of Chemistry, Iran University of Science and Technology, Tehran, Iran.

The thermal stability and photo-bactericidal effect of several tetra-cationic porphyrins and their zinc ion compounds immobilized onto cellulosic fabrics against S. aureus, P. aeruginosa, and E. coli were investigated and compared using a 100 W tungsten lamp. Immobilization of various concentrations of these photosensitizers onto cellulosic fabrics was carried out and characterized by ATR-FT-IR, DRS, TGA, and SEM. Applied cellulosic fabrics with the photosensitizers exhibited remarkable photo-stability, thermal stability, and antimicrobial activity against these studied strains.
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http://dx.doi.org/10.1111/php.13353DOI Listing
March 2021

New 1,2,3-triazole-(thio)barbituric acid hybrids as urease inhibitors: Design, synthesis, in vitro urease inhibition, docking study, and molecular dynamic simulation.

Arch Pharm (Weinheim) 2020 Sep 28;353(9):e2000023. Epub 2020 Jun 28.

Endocrinology and Metabolism Research Center, Endocrinology and Metabolism Clinical Sciences Institute, Tehran University of Medical Sciences, Tehran, Iran.

A new series of 1,2,3-triazole-(thio)barbituric acid hybrids 8a-n was designed and synthesized on the basis of potent pharmacophores with urease inhibitory activity. Therefore, these compounds were evaluated against Helicobacter pylori urease. The obtained result demonstrated that all the synthesized compounds, 8a-n, were more potent than the standard urease inhibitor, hydroxyurea. Moreover, among them, compounds 8a, 8c-e, 8g,h, and 8k,l exhibited higher urease inhibitory activities than the other standard inhibitor used: thiourea. Docking studies were performed with the synthesized compounds. Furthermore, molecular dynamic simulation of the most potent compounds, 8e and 8l, showed that these compounds interacted with the conserved residues Cys592 and His593, which belong to the active site flap and are essential for enzymatic activity. These interactions have two consequences: (a) blocking the movement of a flap at the entrance of the active site channel and (b) stabilizing the closed active site flap conformation, which significantly reduces the catalytic activity of urease. Calculation of the physicochemical and topological properties of the synthesized compounds 8a-n predicted that all these compounds can be orally active. The ADME prediction of compounds 8a-n was also performed.
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http://dx.doi.org/10.1002/ardp.202000023DOI Listing
September 2020

Improvement of Power Conversion Efficiency of Quantum Dot-Sensitized Solar Cells by Doping of Manganese into a ZnS Passivation Layer and Cosensitization of Zinc-Porphyrin on a Modified Graphene Oxide/Nitrogen-Doped TiO Photoanode.

ACS Omega 2020 May 8;5(19):11024-11034. Epub 2020 May 8.

Department of Chemistry, Iran University of Science and Technology, Tehran 16846-13114, Iran.

It is vital to acquire power conversion efficiencies comparable to other emerging solar cell technologies by making quantum dot-sensitized solar cells (QDSSCs) competitive. In this study, the effect of graphene oxide (GO), nitrogen, manganese, and a porphyrin compound on the performance of QDSSCs based on a TiO/CdS/ZnS photoanode was investigated. First, adding GO and nitrogen into TiO has a conspicuous impact on the cell efficacy. Both these materials reduce the recombination rate and expand the specific surface area of TiO as well as dye loading, reinforcing cell efficiency value. The maximum power conversion efficiency of QDSSC with a GO N-doped photoelectrode was 2.52%. Second, by employing Mn (5 and 10 wt %) doping of ZnS, we have succeeded in considerably improving cell performance (from 2.52 to 3.47%). The reason for this could be for the improvement of the passivation layer of ZnS by Mn ions, bringing about to a smaller recombination of photoinjected electrons with either oxidized dye molecules or electrolyte at the surface of titanium dioxide. However, doping of 15 wt % Mn had an opposite effect and somewhat declined the cell performance. Finally, a Zn-porphyrin dye was added to the CdS/ZnS by a cosensitization method, widening the light absorption range to the NIR (near-infrared region) (>700 nm), leading to the higher short-circuit current density () and cell efficacy. Utilizing an environmentally safe porphyrin compound into the structure of QDSSC has dramatically enhanced the cell efficacy to 4.62%, which is 40% higher than that of the result obtained from the TiO/CdS/ZnS photoelectrode without porphyrin coating.
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http://dx.doi.org/10.1021/acsomega.0c00855DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7241021PMC
May 2020

Design and synthesis of 4,5-diphenyl-imidazol-1,2,3-triazole hybrids as new anti-diabetic agents: in vitro α-glucosidase inhibition, kinetic and docking studies.

Mol Divers 2020 Mar 18. Epub 2020 Mar 18.

Endocrinology and Metabolism Research Center, Endocrinology and Metabolism Clinical Sciences Institute, Tehran University of Medical Sciences, Tehran, Iran.

Fourteen novel 4,5-diphenyl-imidazol-1,2,3-triazole hybrids 8a-n were synthesized with good yields by performing click reaction between the 4,5-diphenyl-2-(prop-2-yn-1-ylthio)-1H-imidazole and various benzyl azides. The synthesized compounds 8a-n were evaluated against yeast α-glucosidase, and all these compounds exhibited excellent inhibitory activity (IC values in the range of 85.6 ± 0.4-231.4 ± 1.0 μM), even much more potent than standard drug acarbose (IC = 750.0 μM). Among them, 4,5-diphenyl-imidazol-1,2,3-triazoles possessing 2-chloro and 2-bromo-benzyl moieties (compounds 8g and 8i) demonstrated the most potent inhibitory activities toward α-glucosidase. The kinetic study of the compound 8g revealed that this compound inhibited α-glucosidase in a competitive mode. Furthermore, docking calculations of these compounds were performed to predict the interaction mode of the synthesized compounds in the active site of α-glucosidase. A novel series of 4,5-diphenyl-imidazol-1,2,3-triazole hybrids 8a-n was synthesized with good yields by performing click reaction between the 4,5-diphenyl-2-(prop-2-yn-1-ylthio)-1Himidazole and various benzyl azides. The synthesized compounds 8a-n were evaluated against yeast α-glucosidase and all these compounds exhibited excellent inhibitory activity (IC50 values in the range of 85.6 ± 0.4-231.4 ± 1.0 μM), even much more potent than standard drug acarbose (IC50 = 750.0 μM).
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http://dx.doi.org/10.1007/s11030-020-10072-8DOI Listing
March 2020

Biscoumarin-1,2,3-triazole hybrids as novel anti-diabetic agents: Design, synthesis, in vitro α-glucosidase inhibition, kinetic, and docking studies.

Bioorg Chem 2019 11 16;92:103206. Epub 2019 Aug 16.

Nano Alvand Company, Avicenna Tech Park, Tehran University of Medical Sciences, Tehran 1439955991, Iran. Electronic address:

A novel series of biscoumarin-1,2,3-triazole hybrids 6a-n was prepared and evaluated for α-glucosidase inhibitory potential. All fourteen derivatives exhibited excellent α-glucosidase inhibitory activity with IC values ranging between 13.0 ± 1.5 and 75.5 ± 7.0 µM when compared with the acarbose as standard inhibitor (IC = 750.0 ± 12.0 µM). Among the synthesized compounds, compounds 6c (IC = 13.0 ± 1.5 µM) and 6g (IC = 16.4 ± 1.7 µM) exhibited the highest inhibitory activity against α-glucosidase and were non-cytotoxic towards normal fibroblast cells. Kinetic study revealed that compound 6c inhibits the α-glucosidase in a competitive mode. Furthermore, molecular docking investigation was performed to find interaction modes of the biscoumarin-1,2,3-triazole derivatives.
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http://dx.doi.org/10.1016/j.bioorg.2019.103206DOI Listing
November 2019

Antiproliferative activity of morpholine-based compounds on MCF-7 breast cancer, colon carcinoma C26, and normal fibroblast NIH-3T3 cell lines and study of their binding affinity to calf thymus-DNA and bovine serum albumin.

J Biomol Struct Dyn 2019 09 5;37(14):3788-3802. Epub 2018 Dec 5.

c Department of Chemistry , Isfahan University of Technology , Isfahan , Iran.

This report describes the results of a study on the antiproliferative activity of the morpholine-based ligand 1,3-bis(1-morpholinothiocarbonyl)benzene () and its nickel(II) complex () against human breast cancer cells (MCF-7), colon carcinoma cells (C26), and normal fibroblast NIH-3T3 cells. showed better cytotoxicity on both cancerous cells relative to normal cells with the highest selective index of 2.22 in MCF-7 cells. The interaction of both compounds with calf thymus DNA (CT DNA) and bovine serum albumin (BSA) was studied using various spectroscopic techniques and analytical methods such as UV - vis titrations, thermal denaturation, circular dichroism, competitive fluorescent intercalator displacement assays, as well as molecular modeling. The fluorescence intensity of the probe molecule increases clearly when and are added to the methylene blue (MB)-DNA system. Furthermore, the binding of and quenches the BSA fluorescence, revealing a 1:1 interaction with a binding constant of about 10 M. Communicated by Ramaswamy H. Sarma.
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http://dx.doi.org/10.1080/07391102.2018.1527724DOI Listing
September 2019

Comparison of Kinetic Study and Protective Effects of Biological Dipeptide and Two Porphyrin Derivatives on Metal Cytotoxicity Toward Human Lymphocytes.

Iran J Pharm Res 2017 ;16(3):1059-1070

Bionorganic Chemistry Research Laboratory, Chemistry Department, Iran University of Science and Technology, Narmak, Tehran, Iran.

In this research, dipeptide (his--alanine) and porphyrin derivatives were choosen for comparing chelating ability of toxic metals such as Al, Cu, Hg and Pb. The reason for choosing these two compounds is that both of them are naturally present in biological systems and comparison of chelating ability of these two compounds has not yet been done. Synthesis and comparison of kinetic study of dipeptide (his--alanine), meso-tetrakis(4-trimethylanilinium) porphyrin (TAPP) and Tetrakis(4-sulfonatophenyl)porphyrin (TPPS) were carried out by our team. In addition, cytotoxicity assays of metals and chelators were also performed using methylthiazoletetrazolium (MTT) test. Furthermore we investigated the protective effect of chelators against cytotoxicity, induced by differenrt toxic metals such as Al, Cu, Hg and Pb on human lymphocytes. EC values on human lymphocytes obtained after 12 h. incubation for Al, Cu and Hg were 30, 51, 3 µM respectively and for Pb no cytotoxicity was observed on human lymphocyte up to 1000 µM concentration. EC obtained for chelators dipeptide, TPPS and TAPP were 948, 472 and 175 µM respectively. Pretreatment of human lymphocyte with subtoxic concentations of chelators reduced toxicity of the metals against human blood lymphocytes.
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http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5610760PMC
January 2017

Enhanced visible light photocurrent response and photodegradation efficiency over TiO2-graphene nanocomposite pillared with tin porphyrin.

J Colloid Interface Sci 2016 Mar 22;466:310-21. Epub 2015 Dec 22.

Department of Chemistry, Faculty of Sciences, Tarbiat Modares University, Tehran 14115-175, Iran.

In this study, a nanostructure material of pillared graphene made of tin porphyrin functionalized graphene-TiO2 composite (TG) was successfully synthesized. The prepared compound showed high activity in the photodegradation reaction under irradiation of visible light. To investigate the effect of graphene as well as dye sensitization on the photoactivity of the catalysts, photocatalytic properties and photocurrent responses of the photocatalyst were examined. Results showed that the composite of graphene-TiO2 containing 3% graphene had the highest photoactivity. Besides, tin porphyrin-pillared TG composite (TGSP) material exhibited an excellent visible light photocatalytic performance in degradation of methyl orange dye. The photoelectrochemical investigations determined that compared with the pure TiO2 electrode, the TGSP electrode exhibited a 23-fold enhancement of photocurrent intensity, suggesting the synergistic effect of the TiO2, the graphene, and the tin porphyrin photosensitizer in these photocatalysts. Furthermore, the mechanism of the photocatalytic process of the synthesized catalysts and the charge transfer mechanism in the prepared TGSP via its band edge positions was also discussed.
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http://dx.doi.org/10.1016/j.jcis.2015.12.046DOI Listing
March 2016

The study of cellulosic fabrics impregnated with porphyrin compounds for use as photo-bactericidal polymers.

Mater Sci Eng C Mater Biol Appl 2016 Feb 21;59:661-668. Epub 2015 Oct 21.

Department of Biology, Faculty of Science, University of Guilan, Rasht, Iran.

In the present work, we report on the preparation of cellulosic fabrics bearing two types of photo-sensitizers in order to prepare efficient polymeric materials for antimicrobial applications. The obtained porphyrin-grafted cellulosic fabrics were characterized by attenuated total reflectance Fourier transform infrared (ATR-FTIR) spectroscopy, diffuse reflectance UV-Vis (DRUV) spectroscopy, thermo-gravimetric analysis (TG) and scanning electron microscopy (SEM). Antimicrobial activity of the prepared porphyrin-cellulose was tested under visible light irradiation against Staphylococcus aureus, Pseudomunas aeroginosa and Escherichia coli. In addition, the effect of two parameters on photo-bactericidal activity of treated fibers was studied: illumination time and concentration of photosensitizers (PS).
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http://dx.doi.org/10.1016/j.msec.2015.10.067DOI Listing
February 2016

Enhanced photobactericidal activity of ZnO nanorods modified by meso-tetrakis(4-sulfonatophenyl)porphyrin under visible LED lamp irradiation.

Water Sci Technol 2015 ;71(8):1249-54

Department of Chemistry, Iran University of Science and Technology, Narmak, Tehran 16846-13114, Iran E-mail:

In this study, zinc oxide (ZnO) nanorods have been synthesized using a simple template-free precipitation technique and deposited on glass substrate. The meso-tetrakis(4-sulfonatophenyl)porphyrin (TPPS) has been synthesized and then immobilized on the surface of ZnO nanorods to prepare an organic/inorganic composite. The samples were characterized by various techniques such as X-ray diffraction, diffuse reflectance spectra, Fourier transform-infrared spectroscopy and scanning electron microscopy. In addition, the photobactericidal activity of TPPS/ZnO composite, TPPS and ZnO nanorods was tested against the pathogenic bacterium of Escherichia coli under visible LED lamp irradiation. The results indicate that the photobactericidal activity of TPPS-loaded ZnO nanorods was better than TPPS or ZnO nanorods, separately.
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http://dx.doi.org/10.2166/wst.2015.098DOI Listing
October 2015

Porous p-NiO/n-Nb2O5 nanocomposites prepared by an EISA route with enhanced photocatalytic activity in simultaneous Cr(VI) reduction and methyl orange decolorization under visible light irradiation.

J Hazard Mater 2015 Apr 24;286:64-74. Epub 2014 Dec 24.

Department of Chemistry, Iran University of Science and Technology, Tehran 16846-13114, Iran. Electronic address:

Porous NiO/Nb2O5 nanocomposites with Ni/Nb molar ratio of 0.4, 0.8 and 1.2 have been obtained via the EISA route using P123 copolymer as organic template, and are assigned as NiNb0.4, NiNb0.8 and NiNb1.2, respectively. For comparison, pure Nb2O5 sample assigned as NiNb0.0 was also synthesized by the same method. Structural and textural features of the as prepared samples were investigated by XRD, FTIR, FE-SEM, EDX, UV-vis DRS and BET techniques. The results indicated that the porous p-NiO/n-Nb2O5 junction nanocomposites were formed and coupling of NiO with Nb2O5 resulted a remarkable red shift in the optical response of the nanocomposite samples. The photocatalytic properties of the nanocomposite samples, and also synthesized pure Nb2O5 (NiNb0.0) and commercial Nb2O5 as reference catalysts were evaluated for the first time by simultaneous Cr(VI) reduction and MO decolorization in aqueous suspension under visible light irradiation at pH 2. NiNb0.4 was found to be the most active photocatalyst, which might be attributed to the extended absorption in the visible light region and the effective photogenerated electron-hole separation by the photosynergistic effects of the p-NiO/n-Nb2O5 composite powder. The photocatalytic efficiency of the most active photocatalyst, NiNb0.4, was found to be rather low for either single Cr(VI) solution or single MO solution. However, the photocatalytic reduction of Cr(VI) and photocatalytic decolorization of MO proceed more rapidly for the coexistence system of Cr(VI) and MO than for the single process, showing synergetic effect between the reduction and decolorization reactions. The effects of initial concentration of Cr(VI), MO and the initial pH value on the rate of simultaneous photoreactions over NiNb0.4 sample, were also investigated. The Cr(VI) and MO removal rates were further enhanced by increasing MO and Cr (VI) concentration to an optimal value, respectively, and/or decreasing solution pH.
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http://dx.doi.org/10.1016/j.jhazmat.2014.12.038DOI Listing
April 2015

Influence of operational key parameters on the photocatalytic decolorization of Rhodamine B dye using Fe2+/H2O2/Nb2O5/UV system.

Environ Sci Pollut Res Int 2014 Apr 28;21(7):5121-31. Epub 2013 Dec 28.

Department of Chemistry, Iran University of Science and Technology, Tehran, 16846-13114, Iran.

The present research deals with the development of a new heterogeneous photocatalysis and Fenton hybrid system for the removal of color from textile dyeing wastewater as Rhodamine B (RhB) solutions by using Fe(2+)/H2O2/Nb2O5 as a photocatalytic system. The application of this photocatalytic system for the decolorization of dye contaminants is not reported in the literature yet. Different parameters like dye concentration, Nb2O5/Fe(2+) catalyst amount, pH, and H2O2 concentration have been studied. The optimum conditions for the decolorization of the dye were initial concentration of 10 mg L(-1) of dye, pH 4, and Nb2O5/Fe(2+) catalyst concentration of 0.5 g L(-1)/50 mg L(-1). The optimum value of H2O2 concentration for the conditions used in this study was 700 mg L(-1). Moreover, the efficiency of the Nb2O5/photo-Fenton hybrid process in comparison to photo-Fenton alone and a dark Fenton process as a control experiment to decolorize the RhB solution has been investigated. The combination of photo-Fenton and Nb2O5 catalysts has been proved to be the most effective for the treatment of such type of wastewaters. The results revealed that the RhB dye was decolorized in a higher percent (78 %) by the Nb2O5/photo-Fenton hybrid process (Fe(2+)/H2O2/Nb2O5/UV) than by the photo-Fenton process alone (37 %) and dark Fenton process (14 %) after 120 min of treatment. Moreover, the Nb2O5 catalyst as a heterogeneous part of the photocatalytic system was demonstrated to have good stability and reusability.
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http://dx.doi.org/10.1007/s11356-013-2456-5DOI Listing
April 2014

Mineral contents of some plants used in Iran.

Pharmacognosy Res 2010 Jul;2(4):267-70

Department of Chemistry, Iran University of Science and Technology, Tehran, Iran.

In this work, mineral contents of 4 plants used in Iran were determined by Inductively Coupled Plasma-Atomic Emission Spectrometry. The concentrations were calculated on a dry weight basis. All materials contained high amounts of Na, Al, Ca, Fe, K, Mg, P, Zn, and I. On a moisture-free basis, the highest levels of Ca, P, and Mg were found in spinach to be 3200 mg/100 g, 2150 mg/100 g, and 460 mg/100 g, respectively. Bi, Cd, Li, Pb, and Se contents of condiments were found to be very low. The results were compared with those from the Spanish, Turkish, and Indian. This work attempts to contribute to knowledge of the nutritional properties of these plants. These results may be useful for the evaluation of dietary information and concluded that the green vegetables are the good sources of minerals.
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http://dx.doi.org/10.4103/0974-8490.69130DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3141140PMC
July 2010

Ultrasonic method for the preparation of organic porphyrin nanoparticles.

Molecules 2009 Jan 12;15(1):280-7. Epub 2009 Jan 12.

Department of Chemistry, Iran University of Science and Technology, Narmak, Tehran, Iran.

We report the synthesis and optical properties of organic porphyrin nanoparticles with narrow size distribution and good dispersibility. Nanoparticles were produced by a combination of precipitation and sonication, termed the "ultrasonic method". The resulting [tetrakis(para-chlorophenyl)porphyrin]TClPP nanoparticles were stable in solution without precipitation for at least 30 days. No self aggregation of the constituent porphyrin chromophores was observed. The TClPP nanoparticles exhibited interesting optical properties, particularly a large bathochromic shift in the absorption spectra.
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http://dx.doi.org/10.3390/molecules15010280DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6257125PMC
January 2009

Aqua-bis[N'-(2-hydroxy-benzyl-idene)isonicotinohydrazide-κN]silver(I) nitrate.

Acta Crystallogr Sect E Struct Rep Online 2010 Feb 13;66(Pt 3):m294. Epub 2010 Feb 13.

In the title compound, [Ag(C(13)H(11)N(3)O(2))(2)(H(2)O)]NO(3), two N atoms from two pyridine rings of two N'-(2-hydroxy-benzyl-idene)isonicotinohydrazide ligands coordinate to the Ag(I) atom, forming a nearly linear geometry with an N-Ag-N angle of 171.63 (6)°; a water O atom is located at the apical site, completing the T-shaped coordination. The crystal structure is stabilized by extensive O-H⋯O, O-H⋯N and N-H⋯O hydrogen bonding.
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http://dx.doi.org/10.1107/S1600536810005027DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2983511PMC
February 2010

Bis(2,6-dimethyl-pyridinium) hexa-chlorido-platinate(IV).

Acta Crystallogr Sect E Struct Rep Online 2008 Aug 9;64(Pt 9):m1143-4. Epub 2008 Aug 9.

The asymmetric unit of the title compound, (C(7)H(10)N)(2)[PtCl(6)], contains one independent protonated 2,6-dimethyl-pyridinium cation and half of a centrosymmetric [PtCl(6)](2-) anion. The Pt atom has an octa-hedral coordination. In the crystal structure, inter-molecular N-H⋯Cl and C-H⋯Cl hydrogen bonds result in the formation of a supra-molecular structure. There is a π-π contact between the pyridine rings [centroid-centroid distance = 4.235 (1) Å].
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http://dx.doi.org/10.1107/S1600536808025257DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2960473PMC
August 2008