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Progress Toward Cariporide Analogs For Sodium-Proton Exchange Inhibition, Jessica Moore, Mark Graves Ii, Jacob A. Vervynckt, William Harley, Fredric Gorin, Hasan Palandoken

Chemistry and Biochemistry

The sodium proton exchanger (NHE) is particularly important in maintaining the intracellular pH in human heart and brain. Under anaerobic conditions (i.e., ischemia), a shift from oxidative to nonoxidative glycolysis occurs. The resultant decrease in the intracellular pH activates NHE, which increases the intracellular sodium, initiating the sequence of physiological events that lead to cell death. Thus, there has been great interest in the development of compounds that inhibit NHE. Indeed, potent NHE inhibitors are available. However, a fundamental impediment to the field is the delivery of these compounds to poorly vascularized tissues during the early phases of ischemia when …

The Effects Of Pc-Based Laboratories On Student Learning, Lester L. Pesterfield, Stuart Burris, Darwin B. Dahl, Hasan Palandoken, Jacqueline Pope-Tarrence

Chemistry and Biochemistry

The Department of Chemistry at Western Kentucky University recently incorporated a net-worked MeasureNet data acquisition and analysis system into in the second semester General Chemistry laboratories. Our investigation team has conducted a study to evaluate the effects of the MeasureNet system on student learning and performance on a Beer's Law laboratory. We focused on two phenomena: the effect of the MeasureNet system on 1) student learning of specific content material and 2) student interest in chemistry and science in general. The study involved a MeasureNet system group (employing a UV-Vis spectrometer and colorimeters) and a control group (employing traditional Spectronic …

Quantitative Measure Of Cytotoxicity Of Anticancer Drugs And Other Agents, Zhimin Tao, Eyone Jones, Jerry Goodisman, Abdul-Kader Souid

Chemistry - All Scholarship

Many anticancer drugs act on cancer cells to promote apoptosis, which includes impairment of cellular respiration (mitochondrial O ₂ consumption). Other agents also inhibit cellular respiration, sometimes irreversibly. To investigate the sensitivity of cancer cells to cytotoxins, including anticancer drugs, we compare the profiles of cellular O ₂ consumption in the absence and presence of these agents. Oxygen measurements are made at 37 °C, using glucose as a substrate, with [O ₂] obtained from the phosphorescence decay rate of a palladium phosphor. The rate of respiration k is defined as -d[O ₂]/dt in a sealed container. Different toxins …

Chemistry & Biochemistry Newsletter, Department Of Chemistry & Biochemistry, South Dakota State University

Chemistry & Biochemistry Newsletter: 2002-2015

Inside:

Page 2 Photodynamic Therapy Offers New Approach to Cancer

Page 3 Chemistry Professor Recognized by Peers as Member of the Year; Department Head Joins NSF Committee

Page 4 Retired SDSU Dean Honored for Distance Education Alliance; Miller receives Edward Patrick Hogan Award; Freshman Chemistry Major Honored

Page 5 2008 Chemistry and Biochemistry Graduates

Page 6 Scholarships and Awards

Fluorescence Characteristics Of Triazine-Manufacturing Wastewater, Lin Huang, Shuyan Qiu, Neissa Pinzon, Li-Ta Lien, Lu-Kwang Ju

Chemical, Biomolecular, and Corrosion Engineering Faculty Research

Samples taken at different points in the wastewater treatment process of a triazine-manufacturing plant were scanned by fluorescence spectroscopy, in the wavelength range of 200-900 nm. Reproducibly, the fluorescence spectra revealed one single major peak at excitation and emission wavelengths of 258 and 370 nm respectively. Aqueous solutions of purified active compounds, including Atrazine, Propazine, Simazine, Terbuthylazine, Metolachlor, and Benoxacor, were also scanned. No significant fluorescence was observed in these standard solutions at concentrations up to 100 mg/L. Selected plant samples as well as standard solutions of Atrazine, Metolachlor, and toluene were further analyzed using high-performance liquid chromatography with absorbance …

Metal Coordination And Cis-Trans Isomerisation Of Benzene Dihydrodiols, Catriona O'Meara

Masters

Abstract In this thesis, a viable route for conversion of arene cis-dihydrodiols to their trans isomers was investigated. The cis-dihydrodiols can be produced by large scale fermentation but their trans analogues are not accessible using this approach. The trans dihydrodiols are potentially important chiral building blocks in synthetic chemistry particularly because they have the advantage that they are more stable than the cis-isomers. The principal aim of this work was to carry out parallel studies to inform the development of the synthetic pathway under study by; (a) synthesis of organometallic and organic intermediates and products and, (b) investigation of the …

Volume 01, Jessica Fields, Stephanie Neeley, Derek W. Hambright, Mary E. Lehman, Andrew R. Grzankowski, Zachary Johnson, Boone M. Prentice, Ashley M. Swandby, Victoria Morgan, Katie Williamson, Kristine G. Bender, Katelyn N. Romaine, D. Nicole Swann, Jessica Fox, Mike Mcateer, Alex Grabiec, Laura Nodtvedt, Nick Costa, Rachel Wolfe, Zack Dalton

Incite: The Journal of Undergraduate Scholarship

Introduction from Dean Dr. Charles Ross

Three Decades of Digging: Undergraduate Archeology at Longwood by Jessica Fields and Stephanie Neeley

Interactions of Allelopathy and Heat Stress in Plants by Derek W. Hambright and Mary E. Lehman

Inertial Electrostatic Confinement D-D Fusion Device: Construction and Simulation by Andrew R. Grzankowski

Shackled Nim by Zachary Johnson

Development of GC-MS and Chemometric Methods for the Analysis of Accelerants in Arson Cases by Boone M. Prentice

A Comparison of Image Analysis Methods in cDNA Microarrays by Ashley M. Swandby

Perceived Sexual Activity of Short and Long-Term Relationships by Victoria Morgan and Katie Williamson

Elderly …

Comment On “Contact Conditions For The Charge In The Theory Of The Electrical Double Layer”, Douglas Henderson, L. B. Bhuiyan

Faculty Publications

Exact results in any field, including statistical mechanics, are both aesthetically pleasing and very valuable in assessing theoretical approximations.

Aequorin And Obelin Mutants With Differing Wavelengths And Bioluminescence, Sylvia Daunert, Sapna K. Deo, Emre Dikici, Laura Rowe

Chemistry Faculty Patents

The invention relates to aequorin and obelin mutants whose emission is shifted with respect to wild type. The shift in emission is accomplished using a combination of mutations of amino acids within aequorin or obelin that affect bioluminescence; use of different types of chromophores, i.e., coelenterazines with variable emission characteristics; and modifications of the photoprotein with fluorophores that will allow for emission of light at longer wavelengths as a result of energy transfer. Additionally, an assay employing aequorin mutants to test for HIV-1 protease inhibitors is disclosed.

Mesoporous Silica Nanoparticles Inhibit Cellular Respiration, Zhimin Tao, Tewodros Asefa, Cole Duncan, Abhishek Anan, Jerry Goodisman

Chemistry - All Scholarship

We studied the effect of two types of mesoporous silica nanoparticles, MCM-41 and SBA-15, on mitochondrial O ₂ consumption (respiration) in HL-60 (myeloid) cells, Jurkat (lymphoid) cells, and isolated mitochondria. SBA-15 inhibited cellular respiration at 25-500/ μg/mL; the inhibition was concentration-dependent and time-dependent. The cellular ATP profile paralleled that of respiration. MCM-41 had no noticeable effect on respiration rate. In cells depleted of metabolic fuels, 50 μg/mL SBA-15 delayed the onset of glucose-supported respiration by 12 min and 200 μg/mL SBA-15 by 34 min; MCM-41 also delayed the onset of glucose-supported respiration. Neither SBA-15 nor MCM-41 affected cellular glutathione. Both …

Three-Dimensional Structure Of Conotoxin Tx3a: A M-1 Branch Peptide Of The M-Superfamily, Owen M. Mcdougal, Matthew W. Turner, Andrew J. Ormond, C. Dale Poulter

Chemistry and Biochemistry Faculty Publications and Presentations

The M-superfamily, one of eight major conotoxin superfamilies found in the venom of the cone snail, contains a Cys framework with disulfide-linked loops labeled 1, 2, and 3 (- CC¹C²C³CC-). M-superfamily conotoxins can be divided into the m-1, -2, -3 and -4 branches, based upon the number of residues located in the third Cys loop between the fourth and fifth Cys residues. Here we provide a three-dimensional solution structure for the m-1 conotoxin tx3a found in the venom of Conus textile. The 15 amino acid peptide, CCSWDVCDHPSCTCC, has disulfide bonds between Cys^{1 …}

4-Hydroxyphenylretinamide (4hpr) Derivatives Regulate Aromatase Activity And Expression In Breast Cancer Cells, Bin Su, Serena M. Mershon, Laura A. Stonerock, Robert W. Curley Jr., Robert W. Brueggemeier

Chemistry Faculty Publications

Recent studies exhibit that 4-hydroxyphenylretinamide (4HPR) decreases aromatase activity in breast and placental cells. The effect of synthetic 4HPR analogs on aromatase and expression was examined in three breast cancer cell lines. Most derivatives did not decrease cellular aromatase activity. Two of the analogs even stimulated aromatase activity at the transcriptional level. Only one derivative significantly decreased aromatase in all three breast cancer cell lines and also suppressed CYP19 gene expression in one of the cell line. Placental microsomal aromatase assay rule out the possibility that this compound directly inhibits the aromatase enzyme. A non-genomic mechanism in suppression of cellular …

Determination Of Endocannabinoid Receptor Antagonist Sr141716 (Rimonabant) In Plasma By Liquid Chromatograph Tandem Mass Spectrometry, Melissa Mcculloch, Xiang Zhou, Yan Xu, Steve Brunell, Linda Spear

Chemistry Faculty Publications

SR141716 (rimonabant) is an endocannabinoid receptor antagonist. Endocannabinoids are a class of chemicals that affect neurotransmission via G-protein coupled CB1 (brain) and CB2 (peripheral tissue) receptors. Numerous animal studies have shown that SR141716 binds with the CB1 receptor in the brain, resulting in several biological consequences including reduced alcohol intake and reward as well as reduced food consumption. In this work, an analytical method based on liquid chromatography and electrospray ionization tandem mass spectrometry (LC–ESI-MS/MS) has been developed and validated for the quantitative measurement of SR141716 in both human and rat plasma to support the investigation of this compound. A …

Relationship Between The Excited State Relaxation Paths Of Rhodopsin And Isorhodopsin, Angela Strambi, Pedro B. Coto, Luis Manuel Frutos, Nicolas Ferre, Massimo Olivucci

Chemistry Faculty Publications

The pigment Isorhodopsin, an analogue of the visual pigment Rhodopsin, is investigated via quantum-mechanics/molecular-mechanics computations based on an ab initio multiconfigurational quantum chemical, treatment. The limited <5 kcal mol(-1) error found for the spectral parameters allows for a nearly quantitative analysis of the excited-state structure and reactivity of its 9-cis-retinal chromophore. We demonstrate that, similar to Rhodopsin, Isorhodopsin features a shallow photoisomerization path. However, the structure of the reaction coordinate appears to be reversed. In fact, while the coordinate still corresponds to an asynchronous crankshaft motion, the dominant isomerization component involves a counterclockwise, rather than clockwise, twisting of the 9-cis bond. Similarly, the minor component involves a clockwise, rather than counterclockwise, twisting of the 11-trans bond. Ultimately, these results indicate that Rhodopsin and Isorhodopsin relax along a common excited-state potential energy valley starting from opposite ends. The fact that the central and lowest energy region of such valley runs along a segment of the intersection space between the ground and excited states of the protein explains why the pigments decay at distinctive conical intersection structures.

Department Of Chemistry News For Alumni And Friends, March 2008, Illinois State University, Department Of Chemistry

Chem Letter

Newsletter of the Illinois State University Department of Chemistry

Effects Of Ionic Strength, Temperature, And Ph On Degradation Of Selected Antibiotics, Keith A. Loftin, Craig D. Adams, Michael T. Meyer, Rao Surampalli

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

Aqueous degradation rates, which include hydrolysis and epimerization, for chlorretracycline (CTC), oxytetracycline (OTC), tetracycline (TET), lincomycin (LNC), sulfachlorpyridazine (SCP), sulfadimethoxine (SDM), sulfathiazole (STZ), trimethoprim (TRM), and tylosin a (TYL) were studied as a function of ionic strength (0.0015, 0.050, or 0.084 mg/L as Na2HPO4), temperature (7, 22, and 35°C), and pH (2, 5, 7, 9, and 11). Multiple linear regression revealed that ionic strength did not significantly affect (α = 0.05) degradation rates for all compounds, but temperature and pH affected rates for CTC, OTC, and TET significand (α = 0.05). Degradation also was observed for TYL at pH 2 …

A Facile And Efficient Synthesis Of Some (6e)-Hydroximino-4-En-3-One Steroids, Steroidal Oximes From Cinachyrella Spp. Sponges, Jianguo Cui, Liliang Huang, Lei Fan, Aimin Zhou

Chemistry Faculty Publications

Using β-sitosterol as a starting material, (6E)-hydroximino-24-ethylcholest-4-en-3-one (1), a natural steroidal oxime from Cinachyrella alloclada and C. apion, was synthesized in four steps with a high overall yield. First, β-sitosterol (5a) is transformed into the corresponding 24-ethylcholest-4-en-3,6-dione (6a) via oxidation with pyridinium chlorochromate (PCC). Selective reduction of 6a by NaBH4 in the presence of CoCl2 gives 24-ethylcholest- 4-en-3β-ol-6-one (7a). The reaction of 7a with hydroxylamine hydrochloride offers the oxime 8a and the oxidation of 8a by Jones reagent gives the target steroid 1. (6E)-Hydroximinocholest-4-en-3-one (2) and (6E)-hydroximino-24-ethylcholest-4,22-dien-3-one (4) were synthesized by a similar method. The cytotoxicity of the synthesized compounds …

Characterization Of Zirconium Nitride Films Sputter Deposited With An Extensive Range Of Nitrogen Flow Rates, N. Farkas, G. Zhang, R. D. Ramsier, Edward A. Evans, J. A. Dagata

Chemical, Biomolecular, and Corrosion Engineering Faculty Research

ZrNx films are deposited by rf magnetron sputtering using a wide range of nitrogen flow rates to control film properties. Scanned probe microscope (SPM) oxidation is presented as a complimentary characterization tool to x-ray diffraction, colorimetric, and four point probe analyses. The SPM oxidation behavior of the ZrNx films is related to their structural, optical, and electrical properties. Whereas stoichiometric ZrN films have applications as protective and/or decorative coatings, ZrNx films sputtered with higher nitrogen flow rates have potential applications in devices where arrays of high aspect ratio nanostructures would be useful. (C) 2008 American Vacuum Society.

Final Report: Nevada System Of Higher Education Quality Assurance Program, Nevada System Of Higher Education

Publications (YM)

The principal purpose of the cooperative agreement was to develop and continue providing the public and the Office of Repository Development (ORD) of the U.S. Department of Energy’s (DOE) Office of Civilian Radioactive Waste Management (OCRWM) with an independently derived, unbiased body of scientific and engineering data concerning the study of Yucca Mountain as a potential high-level radioactive waste repository. Under this agreement, the Nevada System of Higher Education (NSHE), formerly the University and Community CollegeSystem of Nevada (UCCSN), performed scientific and engineering research, and maintained and fostered collaborative working relationships between government and academic researchers. In performing these activities, …

Determination Of Enantiomeric Compositions Of Analytes Using Novel Fluorescent Chiral Molecular Micelles And Steady State Fluorescence Measurements, Alicia A. Williams, Sayo O. Fakayode, Onur Alptürk, Christina M. Jones, Mark Lowry, Robert M. Strongin, Isiah M. Warner

Chemistry Faculty Publications and Presentations

Novel fluorescent chiral molecular micelles (FCMMs) were synthesized, characterized, and employed as chiral selectors for enantiomeric recognition of non-fluorescent chiral molecules using steady state fluorescence spectroscopy. The sensitivity of the fluorescence technique allowed for investigation of low concentrations of chiral selector (3.0 x 10(-5) M) and analyte (5.0 x 10(-6) M) to be used in these studies. The chiral interactions of glucose, tartaric acid, and serine in the presence of FCMMs poly(sodium N-undecanoyl-L-tryptophanate) [poly-L-SUW], poly(sodium N-undecanoyl-L-tyrosinate) [poly-L-SUY], and poly(sodium N-undecanoyl-L-phenylalininate) [poly-SUF] were based on diastereomeric complex formation. Poly-L-SUW had a significant fluorescence emission spectral difference as compared to poly-L-SUY and …

Equation Of State Of Gallium Oxide To 70 Gpa: Comparison Of Quasihydrostatic And Nonhydrostatic Compression, Kristina E. Lipinska-Kalita, Patricia Kalita, Oliver Hemmers, Thomas Hartmann

Environmental Studies Faculty Publications

Synchrotron x-ray diffraction and diamond-anvil cell techniques were used to characterize pressure induced structural modifications in gallium oxide. Gallium oxide was studied on compression up to 70 GPa and on the following decompression. The effect of the pressure-transmitting medium on the structural transformations was investigated in two sets of compression and decompression runs, one with nitrogen as a quasihydrostatic pressure-transmitting medium and the other in nonhydrostatic pressure conditions. The x-ray diffraction data showed gradual phase transition from a low-density, monoclinic β-Ga₂O₃ to a high-density, rhombohedral α-Ga₂O₃. With the use of nitrogen as a …

Oxygenation Of The Root Zone And Tce Remediation: A Plant Model Of Rhizosphere Dynamics, Ian F. Thompson

Theses and Dissertations

This study analyzes rhizosphere conditions that enhance the effective aerobic degradation of TCE in wetland bioremediation systems. A plant model was built using Stella 9.0 modeling software and uses numerical integration evaluation; it addresses movement of oxygen through plant vascular and aerenchymal systems, and into the rhizosphere where oxygen and other substrates influence bacteria. Methanotrophs and heterotrophs are assumed to be influential bacteria groups. Variations of humidity-induced-convection, methane, soil carbon, and copper concentrations are evaluated. Varying concentrations and hydraulic loadings of TCE are assessed with respect to TCE consumption rate and TCE treatment efficiency. Soil conditions most directly affected TCE …

Study On The Binding Mode Of In(Bpy)Cl3·H2O With Dna By The Methods Of Electrochemistry, Jun-Wei Wang, Jian-Guo Ren, Bao-Juan Zhou, Xiao-Ling Gao, Yan-Ni Tian

Journal of Electrochemistry

The complex In(bpy)Cl₃·H₂O was synthesized.The binding mode of the complex with DNA was studied by the methods of cyclic voltammetry(CV),differential pulse voltammetry and ac impedance in the buffer Tris-HCl(pH=7.2).A quasi-reversible redox wave for the central Indium ion from the cyclic voltammograms was shown at a PG electrode.It has been found that after the complex acted with DNA,The complex's formal potential negatively shifted from-0.696 V to-0.717 V,the values of the reduction peak current and apparent diffusion coefficient decreased significantly.The results of differential pulse voltammetry were the same as cyclic voltammetry,and the electrochemical reaction resistance values increased from …

4-(4-Chlorophenyl)-5-[1-(4-Chlorophenyl)-2-Methyl-2-Nitropropyl]-1,2,3-Selenadiazole, A. Marx, S. Saravanan, S. Muthusubramanian, V. Manivannan, Nigam Rath

Chemistry & Biochemistry Faculty Works

In the title compound, C18H15Cl2N3O2Se, the selenadiazole ring makes dihedral angles of 49.87 (3) and 55.70 (3)° with the two benzene rings. The dihedral angle between the two benzene rings is 11.90 (5)°. In the crystal structure, intra­molecular C-H...O and C-H...Se inter­actions and inter­molecular C-H...O, C-H...Cl and C-H...N inter­actions are observed.

Quenching Of Highly Vibrationally Excited Pyrimidine By Collisions With Co4, Jeremy A. Johnson, Andrew M. Duffin, Brian J. Hom, Karl E. Jackson, Eric T. Sevy

Faculty Publications

Relaxation of highly vibrationally excited pyrimidine (C4N2H4) by collisions with carbon dioxide has been investigated using diode laser transient absorption spectroscopy. Vibrationally hot pyrimidine (E'=40,635 cm^-1) was prepared by 248-nm excimer laser excitation, followed by rapid radiationless relaxation to the ground electronic state. The nascent rotational population distribution (J=58–80) of the 0000 ground state of CO2 resulting from collisions with hot pyrimidine was probed at short times following the excimer laser pulse. Doppler spectroscopy was used to measure the CO2 recoil velocity distribution for J=58–80 of the 0000 state. Rate constants and probabilities for collisions populating these CO2 rotational states …

Ozone Exposure In A Mouse Model Induces Airway Hyperreactivity That Requires The Presence Of Natural Killer T Cells And Il-17, Paul B. Savage, Muriel Pichavant, Sho Goya, Everett H. Meyer, Richard A. Johnston, Hye Y. Kim, Ponpan Matangkasombut, Ming Zhu, Yoichiro Iwakura, Rosemarie H. Dekruyff, Stephanie A. Shore, Dale T. Umetsu

Faculty Publications

Exposure to ozone, which is a major component of air pollution, induces a form of asthma that occurs in the absence of adaptive immunity. Although ozone-induced asthma is characterized by airway neutrophilia, and not eosinophilia, it is nevertheless associated with airway hyperreactivity (AHR), which is a cardinal feature of asthma. Because AHR induced by allergens requires the presence of natural killer T (NKT) cells, we asked whether ozone-induced AHR had similar requirements. We found that repeated exposure of wild-type (WT) mice to ozone induced severe AHR associated with an increase in airway NKT cells, neutrophils, and macrophages. Surprisingly, NKT cell-deficient …

Discrete Sums For The Rapid Determination Of Exponential Decay Constants, Michael A. Everest, Dean B. Atkinson

Chemistry Faculty Publications and Presentations

Several computational methods are presented for the rapid extraction of decay time constants from discrete exponential data. Two methods are found to be comparably fast and highly accurate. They are corrected successive integration and a method involving the Fourier transform (FT) of the data and the application of an expression that does not assume continuous data. FT methods in the literature are found to introduce significant systematic error owing to the assumption that data are continuous. Corrected successive integration methods in the literature are correct, but we offer a more direct way of applying them which we call linear regression …

A Dynamic Bayesian Network Approach To Protein Secondary Structure Prediction, Xin-Qiu Joe Yao, Huaigiu Zhu, Zhen-Su She

Chemistry Faculty Publications

Background

Protein secondary structure prediction method based on probabilistic models such as hidden Markov model (HMM) appeals to many because it provides meaningful information relevant to sequence-structure relationship. However, at present, the prediction accuracy of pure HMM-type methods is much lower than that of machine learning-based methods such as neural networks (NN) or support vector machines (SVM).

Results

In this paper, we report a new method of probabilistic nature for protein secondary structure prediction, based on dynamic Bayesian networks (DBN). The new method models the PSI-BLAST profile of a protein sequence using a multivariate Gaussian distribution, and simultaneously takes into …

Strictosidine Synthase: Mechanism Of A Pictet-Spengler Catalyzing Enzyme, Justin J. Maresh, Lesley Ann Giddings, Anne Friedrich, Elke A. Loris, Santosh Panjikar, Bernhardt L. Trout, Joachim Stöckigt, Baron Peters, Sarah E. O'Connor

Chemistry: Faculty Publications

The Pictet-Spengler reaction, which yields either a β-carboline or a tetrahydroquinoline product from an aromatic amine and an aldehyde, is widely utilized in plant alkaloid biosynthesis. Here we deconvolute the role that the biosynthetic enzyme strictosidine synthase plays in catalyzing the stereoselective synthesis of a β-carboline product. Notably, the rate-controlling step of the enzyme mechanism, as identified by the appearance of a primary kinetic isotope effect (KIE), is the rearomatization of a positively charged intermediate. The KIE of a nonenzymatic Pictet-Spengler reaction indicates that rearomatization is also rate-controlling in solution, suggesting that the enzyme does not significantly change the mechanism …

Monolayer-Protected Nanoparticle Film Assemblies As Platforms For Controlling Interfacial And Adsorption Properties In Protein Monolayer Electrochemistry, Andrew F. Loftus, Katelyn P. Reighard, Susanna A. Kapourales, Michael C. Leopold

Chemistry Faculty Publications

Assembled films of nonaqueous nanoparticles, known as monolayer-protected clusters (MPCs), are investigated as adsorption platforms in protein monolayer electrochemistry (PME), a strategy for studying the electron transfer (ET) of redox proteins. Modified electrodes featuring MPC films assembled with various linking methods, including both electrostatic and covalent mechanisms, are employed to immobilize cytochrome c (cyt c) for electrochemical analysis. The background signal (non-Faradaic current) of these systems is directly related to the structure and composition of the MPC films, including nanoparticle core size, protecting ligand properties, as well as the linking mechanism utilized during assembly. Dithiol-linked films of Au225(C6)75 are …