Browsing by Author "Jalilehvand, Farideh"
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Item Open Access Acidity and Salt Precipitation on the Vasa; The Sulfur Problem(International Council of Museums, Committee for Conservation - Wet Organic Archaeological Materials, 2001) Jalilehvand, Farideh; Sandstrom, Magnus; Persson, Ingmar; Gelius, Ulrik; Frank, PatrickItem Open Access Analyses of sulfur and iron in marine-archaeological wood(International Council of Museums, 2005) Jalilehvand, Farideh; Sandström, Magnus; Fors, Yvonne; Damian, Emiliana; Gelius, UlrikItem Open Access Cadmium (II) Complex Formation with N-Acetylcysteine, Selenourea and Thiourea in Solution(2012-09-28) Amini, Zahra; Jalilehvand, FaridehCd(II) complexes with N-acetylcysteine (H2NAC), selenourea (SeU), and thiourea (TU) in solution were investigated using NMR and XAS spectroscopic techniques. From the Cd K-edge EXAFS spectrum of a Cd(II)-SeU methanol solution at 200 K containing CCd(II)=0.1 M and CSeU≥0.4 M, the local structure of a Cd(SeU)4 tetrahedral species with Cd-Se bond distance of was determined. NMR measurement of this solution shows a single sharp peak at 578 ppm, which is in agreement with the reported speciation. For Cd(II)-SeU solutions with a lower concentration of selenourea, a mixture of species was observed. NMR spectra of Cd(II)-TU solutions revealed a mixture of species at low TU/Cd(II) mole ratios. The structures of these complexes were determined using Cd K-edge EXAFS spectroscopy, LIII-edge XANES, and NMR. Cd(II)-N-acetylcysteine solutions with CCd(II) = 0.1 M and NAC/Cd(II) mole ratios of 2.0–20.0 at pH = 7.5 and 11.0 have been investigated. They show a mixture of CdS3O3, CdS3O, and CdS4 species at low NAC concentration and species at high NAC concentration.Item Open Access Complex formation of antitumor active dirhodium(II) acetate with small molecules of biological interest(2012) Niksirat, Pantea; Jalilehvand, FaridehDirhodium(II) acetate, consisting of Rh2(CH3COO)4 complexes, is a compound with significant antitumor activities and limited side effects. Although the antitumor studies are mostly focused on its interaction with DNA, the mechanism is not recognized yet. In addition to DNA, other biological molecules such as amino acids can interact with this complex. In this dissertation the interaction of Rh2(CH3COO)4 with the amino acids cysteine, methionine and imidazole, which is the side chain of the amino acid histidine, have been investigated using different spectroscopic techniques including EXAFS, multinuclear NMR, IR, ESI-MS and UV-Vis spectroscopy. A pink solid complex Rh2(CH3COO)4(lm)2 was formed from the reaction of Rh2(CH3COO)4 and imidazole (Im) in the mole ratio 1 :2, where the imidazole ligands were coordinated through the axial positions of the Rhi(CH3COO)4 complex with the RhN bond distance 2.25 ± 0.02 A. In a freshly prepared aqueous solution of Rh2(CH3COO)4 and methionine (Met) in the mole ratio 1:2, axial coordination of methionine ligands occurs m Rhi(CH3COO)4(Met)1.2 complexes, with the average bond distances of 2.03 ± 0.02 A, 2.47 ± 0.04 A and 2.40 ± 0.02 A for the Rh-O, Rh-S and Rh-Rh bonds, respectively. Replacement of acetate in equatorial sites with methionine takes place over a period of 2 - 4 weeks, when the solution is saturated with methionine. The composition of the complexes gradually changes from Rhi(CH3COO)4(S-Meth to [Rh2(CH3COO)4.n(S,OMet)n](CH3COO)n (n = 2 - 4), with peaks at 4685 ppm and 4616 ppm in the 103Rh NMR spectrum, more shielded than the resonance 8 (103Rh) = 7476.2 ppm for the hydrated Rhi(CH3COO)4(H2Oh complex, with water molecules as axial ligands. An EXAFS spectrum measured after 10 months of Rh2(CH3COO)4 dissolved in saturated methionine solution gives the average bond distances 2.03, 2.29 and 2.55 ± 0.02 A for the Rh-O, RhS and Rh-Rh bonds, respectively, assuming [Rh2(CH3COO)4_n(Met)n] (n = 2 - 4) species. The shorter Rh-Sand longer Rh-Rh distances, relative to those of Rhi(CH3COO)4(Met)1_2, confirm the equatorial coordination of the methionine ligands. By dissolving Rh2(CH3COO)4 in ethanethiol a Rh2(CH3COO)4(EtSHh complex is formed, with Rh-Rh and Rh-S bond distances of 2.41 ± 0.02 A and 2.53 ± 0.02 A. The UV-Vis spectra of Rh2(CH3COO)4 dissolved in water, ethanethiol, saturated methionine solution and 0.1 M / 1.0 M imidazole solutions show peak maxima at Amax = 588, 556, 537 and 521 nm, respectively, which imply that the ligand field strength for these axially coordinated ligands (X) in Rh2(CH3COO)2_4X2 is: X = H2O < EtSH (thiol) < methionine (thioether) < imidazole (Nsp2). Ethanethiol has a single functional group (-SH), and in its reaction with Rhi(CH3COO)4, the Rh-Rh bond remains intact. However, the chelating thiol-containing ligands cysteine (H2Cys) and N-acetylcysteine (H2NAC), are capable of breaking the RhRh bond in their reaction with Rhi(CH3COO)4, to form mononuclear and binuclear Rh(III) species, respectively. In the solid [Rh(iii)HCys)(Cys)(H2O)].H2O compound, cysteine coordinates to Rh(III) ion through its thiol, amine and / or carboxylate groups, with average bond distances of Rh-(N/O) 2.17 ± 0.02 A and Rh-S 2.37 ± 0.02 A. In the solid [Rh111i(HNACh(NACh(H2O)4].2H2O compound, the only available coordination sites of N-acetylcysteine are its thiol and carboxylate groups. The oxidation state +3 for the rhodium ions was confirmed by Rh L3-edge XANES and magnetic susceptibility measurements.Item Open Access Complex formation of Hg(II), Cd(II), and Ag(I) with cysteine and penicillamine(2006) Leung, Bonnie O.; Jalilehvand, FaridehItem Open Access Complex Formation of Mercury(II) with Cysteine in Aqueous Solution(2006) Jalilehvand, Farideh; Leung, Bonnie O.Item Open Access Complex Formation of Pb(II) with Cysteine, Penicillamine and N-acetylcysteine(2014-09-04) Sisombath, Natalie Sinh; Jalilehvand, FaridehThe mechanism of lead poisoning and interest in metal toxicity has been a growing area of study since the late 1950s. In order to gain insight on how toxic metals behave physiologically, simple molecules can first be used to model the environments. Complex formation between Pb(II) and thiol-containing ligands D-penicillamine, L- cysteine and N-acetyl-L-cysteine were investigated in this study. The complexes formed were studied by 207Pb, 13C, 1H NMR, UV-Vis, ESI-MS, and X-ray absorption spectroscopy. The results of the study provide spectroscopic finger prints for Pb(II) coordination environments relevant to biological systems. The study revealed that small structural changes between each ligand, plays a large role in the manner at which they bind to the lead(II) centre.Item Open Access Cytotoxic, Cellular Uptake, and Photophysical Properties of Various Re(I) Tricarbonyl Complexes(2019-09-20) Capper, Miles S.; Jalilehvand, Farideh; Heyne, Belinda; Roesler, Roland; Gailer, Jürgen; Derksen, Darren J.A series of Re(I) tricarbonyl complexes with the general formula, fac-[Re(CO)3(2,2’-bipyridine)(X)]-/0 (X= L-cysteine; N-acetyl-L-cysteine; thiosulfate) were characterized using spectroscopic techniques and single-crystal X-ray diffraction. Photophysical, as well as singlet oxygen (1O2) generation and CO releasing properties were assessed. Cell viability of the complexes against the MDA-MB-231 breast cancer cell line were determined. Cellular localization and accumulation were investigated using synchrotron-based X-ray fluorescence microscopy (XFM). The results of this study show the cytotoxicity, cellular uptake and photophysical properties of fac-[Re(CO)3(bpy)X]+/0/- complexes (X= H2O, HCys-, NAC2-, S2O32-; bpy=2,2’-bipyridine). The cytotoxicity of fac-[Re(CO)3(bpy)(H2O)]+ is diminished when the aqua ligand is replaced by cysteine or thiosulfate.Item Open Access Cytotoxicity, cellular localization and photophysical properties of Re(I) tricarbonyl complexes bound to cysteine and its derivatives(Springer Nature, 2020-06-24) Capper, Miles S.; Enriquez Garcia, Alejandra; Macia, Nicolas; Lai, Barry; Lin, Jian-Bin; Nomura, Masaharu; Alihosseinzadeh, Amir; Ponnurangam, Sathish; Heyne, Belinda; Shemanko, Carrie S.; Jalilehvand, FaridehThe potential chemotherapeutic properties coupled to photochemical transitions make the family of fac-[Re(CO)3(N,N)X]0/+ (N,N = a bidentate diimine such as 2,2'-bipyridine (bpy); X = halide, H2O, pyridine derivatives, PR3, etc.) complexes of special interest. We have investigated reactions of the aqua complex fac-[Re(CO)3(bpy)(H2O)](CF3SO3) (1) with potential anticancer activity with the amino acid l-cysteine (H2Cys), and its derivative N-acetyl-l-cysteine (H2NAC), as well as the tripeptide glutathione (H3A), under physiological conditions (pH 7.4, 37 °C), to model the interaction of 1 with thiol-containing proteins and enzymes, and the impact of such coordination on its photophysical properties and cytotoxicity. We report the syntheses and characterization of fac-[Re(CO)3(bpy)(HCys)]·0.5H2O (2), Na(fac-[Re(CO)3(bpy)(NAC)]) (3), and Na(fac-[Re(CO)3(bpy)(HA)])·H2O (4) using extended X-ray absorption spectroscopy, IR and NMR spectroscopy, electrospray ionization spectrometry, as well as the crystal structure of {fac-[Re(CO)3(bpy)(HCys)]}4·9H2O (2 + 1.75 H2O). The emission spectrum of 1 displays a variance in Stokes shift upon coordination of l-cysteine and N-acetyl-l-cysteine. Laser excitation at λ = 355 nm of methanol solutions of 1–3 was followed by measuring their ability to produce singlet oxygen (1O2) using direct detection methods. The cytotoxicity of 1 and its cysteine-bound complex 2 was assessed using the MDA-MB-231 breast cancer cell line, showing that the replacement of the aqua ligand on 1 with l-cysteine significantly reduced the cytotoxicity of the Re(I) tricarbonyl complex. Probing the cellular localization of 1 and 2 using X-ray fluorescence microscopy revealed an accumulation of 1 in the nuclear and/or perinuclear region, whereas the accumulation of 2 was considerably reduced, potentially explaining its reduced cytotoxicity.Item Open Access Deterioration of the seventeenth-century warship Vasa by internal formation of sulphuric acid(Nature Publishing Group, 2002) Jalilehvand, Farideh; Sandström, Magnus; Persson, Ingmar; Gelius, Ulrik; Frank, Patrick; Hall-Roth, IngridItem Open Access Employing a Metallomics Tool to Probe Bioinorganic Processes in the Bloodstream(2020-04-27) Sarpong-Kumankomah, Sophia; Gailer, Jürgen G.; Thurbide, Kevin B.; Jalilehvand, Farideh; Ling, Changchun; Niyogi, SomIn this thesis, I have applied a metallomics method that is based on size exclusion chromatography coupled on-line to an inductively coupled plasma atomic emission spectrometer (SEC-ICP-AES) to analyze biological fluids to gain insight into the bioinorganic chemistry of metals and their possible link to disease processes. The first study involved the qualitative identification of an iron-containing protein in blood plasma. One of the two major iron-containing proteins in human plasma was identified as a haptoglobin-hemoglobin (Hp-Hb) complex that is formed in plasma after red blood cells rupture. Previously identified plasma metalloproteins - transferrin, ceruloplasmin and α2-macroglobulin were also unequivocally confirmed. Since the employed metallomics method can measure the concentration of these metalloproteins in plasma, the results are important as the quantification of the Hp-Hb complex in plasma gave better insight into the lysis of red blood cells, which is of immediate health relevance. In the second study, the metallomics method was applied to investigate the potential of using plasma metalloproteins as disease biomarkers. Blood serum samples from multiple sclerosis patients (21), stroke patients (17) and healthy controls (21) were analyzed for copper, iron and zinc metalloproteins. The results revealed that the concentration of the Hp-Hb complex in serum was statistically significantly higher in stroke patients compared to the other groups, which can be rationalized by the rupturing of red blood cells during a stroke event. Since 330,000 people in Canada live with long term disability effects of stroke, my results demonstrate the usefulness of the developed analytical method to diagnose diseases. The third study involved the application of the metallomics method to gain insight into the plasma transport of an arsenic-selenium compound, [(GS)2AsSe]-, that is formed in red blood cells and is excreted in bile. The analysis of [(GS)2AsSe]- added to human plasma demonstrated that [(GS)2AsSe]- mobilized Zn from plasma proteins in a dose-dependent manner. The formation of [(GS)2AsSe]- in red blood cells and its release into plasma may perturb the metabolism of zinc therein and result in systemic toxic effects. These results are relevant because the mobilization of zinc is potentially implicated in the chronic exposure of human to AsIII, which currently affects >100 million people. Lastly, the metallomics method was employed to gain insight into the stability of a bimetallic complex that has anti-cancer activity in human blood plasma. The fact that ~70 % of Titanocref remains intact in plasma after 60 min implies that this anti-cancer drug is likely to reach cancer cells in vivo. These results exemplify that conceptually-straightforward in vitro studies can provide important insight into the degradation of a bimetallic anti-cancer drug in plasma. Metallomics studies are therefore destined to play an important role in the context of advancing more metal-based drugs to preclinical studies.Item Open Access Heavy metal complex formation with glutathione(2009) Mah, Vicky; Jalilehvand, FaridehItem Open Access Hydration of some large and highly charged metal ions(Blackwell Publishing, 2001) Jalilehvand, Farideh; Sandström, Magnus; Persson, Ingmar; Lindquist-Reis, Patric; Spangberg, Daniel; Hermansson, KerstiItem Embargo Molecular Imprinting of Metal-Organic frameworks (MOFs) for Selective Separations(2022-04) Evans, David; Shimizu, George; Ling, Chang-Chun; Jalilehvand, FaridehThis thesis explores the idea of using chromium(III) ions and an orthogonal polyaromatic phosphonate linker to produce a stable metal-organic framework (MOF) for the separation of xylene isomers. This began by creating a charge-assisted hydrogen-bonded metal-organic framework (HMOF) that uses weaker interactions to hold the framework together. The orthogonalized phosphonate creates pores due to its bulky nature that prevents efficient ligand packing. In tandem, this allows for the inclusion of guest molecules within the HMOF structure. Once the guest-incorporated structure is formed, heating can remove water molecules from the HMOF to form coordination bonds between the chromium and the phosphonate ligand. This dehydration locks the template in place as it converts to a coordinated metal-organic framework (MOF). The template for this technique is of great importance since you can imprint the pore to a specific molecule. For this study, the xylene isomers ortho, meta, and para, were looked at for separation. The separation of xylenes is of great importance since the different isomers are used in a variety of different applications, such as para-xylene for terephthalic acid (TPA) to manufacture polyethylene terephthalate (PET). The problem with separating xylenes is how expensive the separation is. Since the xylene isomers have very similar boiling points and sizes, either cryogenic distillation or recrystallization has to be performed to acquire a pure product. On this note, three different chromium phosphonate HMOFs were developed. The first structure incorporated a para-xylene template (HCALF 50αP) while the second structure incorporated ortho-xylene as the template (HCALF 50α)). The final structure used meta-xylene as a template (HCALF 50M). These HMOFs were dehydrated into the corresponding MOF structures and used to test selective xylene separation. Initial studies using a static separation and nuclear magnetic resonance (NMR) spectroscopy were conducted followed by a flow-through separation using high-pressure liquid chromatography (HPLC) and a MOF-packed column. The findings were intriguing showing selectivity towards para-xylene for some of the materials. Most notable is that HCALF 50βM showed anti-selectivity towards para-xylene allowing it to flow freely through and making it easier to collect.Item Open Access Nuclear localization of dirhodium(II) complexes in breast cancer cells by X-ray fluorescence microscopy(The Royal Society of Chemistry, 2019-06-05) Enriquez Garcia, Alejandra; Lai, Barry; Gopinathan, Sesha Gopal; Harris, Hugh H.; Shemanko, Carrie S.; Jalilehvand, FaridehThe cellular distribution of three dirhodium(II) complexes with a paddlewheel structure was investigated using synchrotron-based X-ray fluorescence microscopy and cell viability studies. Complexes with vacant axial sites displayed cytotoxic activity and nuclear accumulation whereas complexes in which the axial positions were blocked showed little to no toxicity nor uptake.Item Open Access Probing the Chemistry of Methylmercury in Mammalian Blood Plasma(2022-01-04) Bridle, Tristen G.; Gailer, Jürgen; Jalilehvand, Farideh; Thurbide, KevinA size-exclusion chromatography-inductively coupled plasma-atomic emission spectroscopy (SEC-ICP-AES) technique was developed for the analysis of mammalian blood plasma for endogenous metalloproteins and exogenous metal species. Parameters related to sample preparation, separation, and detection were optimized. The blood plasma was filtered through a 0.45 ?m pore size syringe filter to preserve the separation performance of the column. The 1:1 dilution of filtered human and rabbit blood plasma in phosphate-buffered saline (PBS) prior to analysis was needed to prevent peak tailing and shoulder formation. An SRT-10C SEC column from Sepax Technologies Inc., when compared to a previously used Superdex 200 Increase SEC column, gave the same number of peaks with similar resolution, but in approximately half the time and with higher peak intensities. The mass recovery of proteins on the SRT-10C SEC column was 96 ± 2%. To explore the role that small molecular weight plasma thiols play in the delivery of methylmercury (CH3Hg+) to transporters located at the placental and blood-brain barriers, the described SEC-ICP-AES technique was applied to the analysis of CH3Hg+-spiked rabbit plasma using PBS mobile phases in the absence and presence of the small-molecular weight (SMW) sulfur compounds L-cysteine (Cys), L-homocysteine (hCys), L-glutathione (GSH), and D-methionine (Met). While Met did not affect the binding of CH3Hg+ to the main plasma protein, rabbit serum albumin (RSA), Cys, hCys, and GSH did. The presence of 50 ?M Cys, hCys, or GSH in the mobile phase resulted in the mobilization of CH3Hg+ from RSA in rabbit plasma and from pure RSA in solution. The SMW-Hg species that formed when hCys was present in the mobile phase was qualitatively identified by electrospray ionization mass spectrometry as CH3Hg-hCys. Using the developed metallomics technique I have found evidence of the formation of SMW-CH3Hg+ species under near-physiological conditions that may be involved in the translocation of CH3Hg+ from blood plasma to the brain.Item Open Access Probing the interaction of dirhodium(II) tetraacetate with sulfur-containing biomolecules(2019-04-29) Enriquez Garcia, Alejandra; Jalilehvand, Farideh; Gailer, Jürgen G.; Roesler, Roland; Vogel, Hans J.; George, Graham N.This thesis investigates the interaction of anticancer active dirhodium(II) tetraacetate, Rh2(AcO)4, with sulphur-containing biomolecules including tripeptide glutathione (GSH) and amino acids methionine, L-cysteine and its derivatives. The thiol-containing biomolecules covered in this study were able to break down the paddlewheel structure of dirhodium(II) tetra-acetate under aerobic aqueous conditions at physiological pH. Characterization of the reaction products using a combination of ESI-Mass spectrometry, UV-vis spectroscopy, 13C CPMAS (cross-polarization magic angle spinning) NMR and X-ray absorption spectroscopy (both extended X-ray absorption fine structure, EXAFS, and X-ray absorption near-edge structure, XANES) revealed dimeric and oligomeric Rh(III) species connected by two or three thiolate bridges. Unlike those, the thioether-containing molecules, methionine (HMet) and S-methyl-L-cysteine (HSMC), initially coordinated to the axial positions of the paddlewheel via the thioether moiety. However, the difference in number of carbon atoms in their side chain led to different reactivities: while methionine formed a stable half-paddlewheel structure with two acetate and two methionine ligands coordinated in a tridentate fashion, [Rh2(AcO)2(S,N,O-Met)2]; the reaction with S-methyl-L-cysteine led immediately to a Rh(III) monomeric product, [Rh(SMC)2-3]+/0. This is most likely due to the increased strain that would result from forming a 5-member chelate in a possible [Rh2(AcO)2(S,N,O-SMC)2] complex. Investigation of the cytotoxicity, cellular uptake and biodistribution of [Rh2(AcO)2(S,N,O-Met)2] as compared to Rh2(AcO)4 in MDA-MB-231 breast cancer cells showed that blocked axial positions in the paddlewheel structure hinder the ability of the complex to enter the cell. This is the first experimental evidence that shows the importance of available axial positions for the cellular uptake of dirhodium(II) carboxylates.Item Open Access Reaction of dirhodium(II) tetraacetate with S-methyl-L-cysteine(Taylor & Francis, 2019-08-12) Brunskill, Valerie; Enriquez Garcia, Alejandra; Jalilehvand, Farideh; Gelfand, Benjamin S.; Wu, MengyaThe reaction of antitumor active dirhodium(II) tetraacetate, [Rh2(AcO)4], with S-methyl-L-cysteine (HSMC) was studied at the pH of mixing (=4.8) in aqueous media at various temperatures under aerobic conditions. The results from UV–vis spectroscopy and electrospray ionization mass spectrometry (ESI–MS) showed that HSMC initially coordinates via its sulfur atom to the axial positions of the paddlewheel framework of the dirhodium(II) complex, and was confirmed by the crystal structure of [Rh2(AcO)4(HSMC)2]. After some time (48?h at 25?°C), or at elevated temperature (40?°C), Rh-SMC chelate formation causes breakdown of the paddlewheel structure, generating the mononuclear Rh(III) complexes [Rh(SMC)2]+, [Rh(AcO)(SMC)2] and [Rh(SMC)3], as indicated by ESI–MS. These aerobic reaction products of [Rh2(AcO)4] with HSMC have been compared with those of the two proteinogenic sulfur-containing amino acids methionine and cysteine. Comparison shows that the (S,N)-chelate ring size influences the stability of the [Rh2(AcO)4] paddlewheel cage structure and its RhII–RhII bond, when an amino acid with a thioether group coordinates to dirhodium(II) tetraacetate.Item Open Access Solution NMR Structure and X-ray Absorption Analysis of the C-terminal Zinc Binding Domain of the SecA ATPase(2005) Jalilehvand, Farideh; Dempsey, B.; Shaw, G. S.; Shilton, B.Item Open Access Structure of Hydrated Ions and Cyano Complexes by X-Ray Absorption Spectroscopy(Royal Institute of Technology, Department of Chemistry, 2000) Jalilehvand, Farideh