Physical Sciences and Mathematics Commons^™

Liquid Chromatography With Tandem Mass Spectrometry Method Development For The Determination Of Β–Defensins In Bovine Milk, Symone T. Whalin

Masters Theses & Specialist Projects

Bovine mastitis, caused by a wide array of pathogens, results in a substantial economic loss for the dairy cattle livestock industry. β-defensins are a part of the bovine’s innate immune system and act as the first line of defense against mastitis. Only foundational research has been done on β-defensins’ ability to treat and prevent mastitis. There have been no analytical methods reported in the literature for analyzing β-defensins in bovine milk. This research aims to create an analytical approach to determine β-defensins in bovine milk. It is challenging to determine an analyte in a complex sample matrix, and milk is …

An Investigation Towards The Synthesis Of A Novel Conformationally Restricted Ethylenediamine Scaffold, Fanny Mai

Theses, Dissertations and Culminating Projects

This study reports the synthesis of a novel conformationally restricted ethylenediamine scaffold that can be explored for drug discovery. There was significant progress in synthesizing the target scaffolds, but future studies are needed to finish this synthesis. This potential ethylenediamine compound may offer new scaffolds for exploration in drug design and orexin receptor antagonists with improved selectivity for OX1R and OX2R.

Real-Time Monitoring Of Paraquat Photodegradation Using Colloidal Gold Surface Enhanced Raman Spectroscopy, Nathan Wilson

Masters Theses & Specialist Projects

Monitoring chemical reactions in aqueous solution is a challenge because most instrumental techniques either are not suited for the rapid timescales, are not sensitive enough to detect products at low concentrations, or do not have sufficient structure-to-spectrum relationships. Raman spectroscopy is a promising method to monitor reactions, as it is fast, dependent on chemical structure, and has little interference from water. However, Raman scattering is generally very weak. Surface-enhanced Raman spectroscopy (SERS) improves the signal strength of Raman spectroscopy by using a metal surface plasmon, or oscillation of the surface’s electrons, to allow for highly selective and sensitive detection and …

Towards The Determination Of Estrone And 17Β-Estradiol In Dairy Cattle Waste Using Solid Phase And Stir Bar Sorptive Extractions With Liquid Chromatography-Mass Spectrometry And Gas Chromatography-Mass Spectrometry, Pallavi Ragi

Masters Theses & Specialist Projects

Steroidal hormones are naturally produced as a part of many physiological processes and are excreted in the urine and feces of animals and humans. Farm animals in concentrated animal feeding operations (CAFOs) are routinely implanted with synthetic and natural hormones to enhance growth and production, contributing significantly to environmental steroid hormone contamination. Every year around 49 tons of estrogens are generated by livestock waste in the United States alone. Due to rainfall and runoff, these steroid hormones reach the environment when animal waste is applied as manure. Studies show that estrogens and other steroidal hormones present in the surface waters …

Design, Synthesis, And Analysis Of Paired Coiled-Coil Peptidic Molecular Building Blocks Used For Linearly Controlled Self-Assembly Of Α-Helical Coiled-Coil Heterodimer Peptide Pairs, Jason Distefano

Chemistry Theses

Molecular building blocks are fundamental to biological synthesis and processes and have been utilized in advanced materials, drugs and drug delivery systems, and biotechnology. Proteins have been used as molecular building blocks for the construction of complex, well-ordered structures. Coiled-coil protein domains are essential subunits used for the oligomerization of protein complexes, gene expression, and structural elements of biological materials. The synthesis and assembly of proteins utilizing coiled-coil motifs are of great scientific interest due to their potential applications in disease treatment, biomechanical motors, nanoscale delivery systems, etc. However, assembling protein complexes with specific morphology is still challenging because …

Synthesis And Characterization Of Silver Thione Complexes, Audrey V. Lawrence

Honors Theses

Coordination polymers are repeating units of a coordination complex that have applications as catalysts, conductors, and magnets. In this work, silver (I) was the metal of choice because it behaves similarly to copper (I), which has been studied much more extensively and thione ligands were chosen due to their potential for forming coordination polymers. These coordination complexes with silver were synthesized by combining silver nitrate with thioacetamide, N,N'-diphenylthiourea, and 2-mercapto-1-methylimidazole. These complexes were characterized via IR spectroscopy, elemental analysis, and X-ray crystallography. Silver thioacetamide was determined to form a coordination complex through the sulfur to form a trigonal crystal lattice …

Synthesis And Study Of Unsymmetrical Bidentate Bis(Phosphino)Pyrrole Ligands And Their Transition Metal Complexes, Julia F. Vidlak

Honors Theses

Our laboratory has reported the synthesis and characterization of a broad library of unsymmetrical bidentate bis(phosphino)pyrrole (BPP) ancillary ligands for use in nickel-catalyzed cross-coupling reactions. The electronic and steric properties of nickel complexes bearing these ligands are examined, and our data support the hypothesis that these ligands produce nickel complexes with electron-deficient metal centers. The syntheses of (BPP)Ni(o-tolyl)Cl precatalysts for utilization in nickel-catalyzed Buchwald-Hartwig Amination are described, and preliminary reactivity studies reveal that (BPP)Ni(o-tolyl)Cl precatalysts are effective in promoting C–N cross-coupling reactions. Finally, we report steric measurements and electronic properties obtained from computed (BPP)NiCl2 and (BPP)Ni(CO)2 complexes, respectively. Additional reactivity …

Target Of Glut4 Regulating Protein Tug-Ubl1 To Treat Insulin Resistant Type Two Diabetes, Megan Kohout

Chemistry Student Work

Type two diabetes mellitus is a highly prevalent disease for which the mechanism of insulin signaling to initiate glucose uptake in cleaving TUG-UBL1 by the protease Usp25m is currently not well understood. As increased insulin resistance can lead to the development of type one insulin deficient diabetes, the knowledge of this pathway may uncover underlying causes of insulin resistance. This research aims to understand the effect and stoichiometry of Usp25m binding to TUG-UBL1 in relationship to the cleavage of TUG-UBL1 initiating translocation of GLUT4 glucose transporter. The action of protease effector PIST will be investigated to understand the importance of …

Bis(Tryptophan) Amphiphiles: Design, Synthesis And Efficacy As Antimicrobial Agents, Michael Mckeever

Dissertations

Amphiphiles play important roles in nature. These molecules contain both hydrophilic and hydrophobic regions, leading to some astonishing properties. The lipid bilayer of the cell membrane is a fascinating organization of amphiphilic phospholipids. Natural and synthetic amphiphiles, such as antimicrobial peptides, interact with the cell membrane. Such interactions can impact transport of molecules across the cell membrane, disrupting cell functions. In this work, a library of tryptophan-containing amphiphiles was synthesized and their antimicrobial properties were explored.

First, a library of bis(tryptophan) amphiphiles was synthesized. Preparation included a coupling reaction of a diamine with tryptophan residues, via their carboxy-termini, at …

Effects Of Electrode Shape On Lithiation Process Of Lithium-Ion Battery Electrodes, Shi-Wei Sun, Jian-Jun Nie, Yi-Cheng Song

Journal of Electrochemistry

This paper studies the influence of electrode shape on the lithiation process of lithium ion batteries. Both experimental observation and numerical simulation are employed to investigate the competitive interaction between the diffusion of lithium ions in both solid and liquid phases and the lithium intercalation reaction at the electrode surface. Experimental cells were prepared with the anode and cathode being placed parallel, leaving the latter embracing the former. An experimental device based on CCD camera was set up for in situ observation of electrode lithiation. The lithiation levels of the graphite anodes were estimated according to the observed color profile. …

Study On Electrochemical Conversion Of Ammonium Sulfate To Ammonium Persulfate In Acetylpyrazine Wastewater, Yi-Jie Wang, Dong-Fang Niu, Xin-Sheng Zhang

Journal of Electrochemistry

Acetylpyrazine is an important spice and also plays important roles in biology, medicine and other fields. However, the wastewater containing ammonium persulfate, ferric ion (Fe³⁺), pyrazine, and a large amount of ammonium sulfate was produced during the production of acetylpyrazine. In this study, ammonium sulfate in acetylpyrazine wastewater was electrolytically converted into ammonium persulfate for economic benefits. Using platinum as an anode and graphite as a cathode, the influence factors of the electrolysis process (including the composition of the anolyte, the current density, the temperature, etc.) were firstly investigated without interference from other compositions. Under the optimal condition, …

Adjusting The Alloying Degree Of Pt3Zn To Improve Acid Oxygen Reduction Activity And Stability, Tian-En Zhang, Ya-Ni Yan, Jun-Ming Zhang, Xi-Ming Qu, Yan-Rong Li, Yan-Xia Jiang

Journal of Electrochemistry

Proton exchange membrane fuel cell (PEMFC) is a new type of energy device, a relatively excellent way to achieve carbon neutrality. However, due to the relatively slow reaction rate of oxygen reduction reaction (ORR) at the cathode, platinum (Pt) is the key material of the cathode catalyst. However, Pt is a kind of noble metal, and its high cost restricts the PEMFC commercialization process. At present, the main approach is to combine transition metals with Pt to prepare Pt-based alloys and to reduce the use of Pt. Pt-based alloys are excellent catalysts for ORR, improving both the activity and stability, …

Electrochemical Degradation Of Oxytetracycline Catalyzed By Fe3O4 Magnetic Nanoparticles, Fang Ying, Shan-Shan Xu, Yan-Bing Xu, Miao-Miao Liang, Jian-Feng Li

Journal of Electrochemistry

The purpose of this study is to optimize the electrochemical degradation of oxytetracycline (OTC) in water using a low cost and simple preparation method. In this paper, the Fe₃O₄ magnetic nanoparticles were used as catalysts to activate the electrochemical oxidation system of peroxydisulfates (PDS) which acted as electrolytes to provide active free radicals in order to improve the degradation of OTC under the condition of applying current. As one of the tetracycline antibiotics (TCs), OTC is one of the most used antibiotics in the world, therefore, it is necessary to study the effective degradation of OTC. By …

Study On Electrodeposition Of Antimony In Choline Chloride-Ethylene Glycol Eutectic Solvent, Hao Wang, Xiao-Zhou Cao, Xiang-Xin Xue

Journal of Electrochemistry

Antimony is a chemically stable metal that has been widely used in industry, military and other fields. The use of electrodeposition to prepare antimony coating has the advantages of simple operation and low cost. The deep eutectic solvent (DES) is a eutectic mixture composed of a hydrogen bond donor and a hydrogen bond acceptor at a fixed molar ratio. It has the advantages of wide electrochemical window, high thermal stability, easy preparation, and low cost. Selecting DES as the electrolyte for electrodeposition can avoid the hydrogen evolution reaction of the aqueous system and the toxicity of ionic liquids. In recent …

Investigation On Electrochemical Processes Of P-Aminothiophenol On Gold Electrode Of Nanostructures, Hui-Yuan Peng, Jia-Zheng Wang, Jia Liu, Huan-Huan Yu, Jian-De Lin, De-Yin Wu, Zhong-Qun Tian

Journal of Electrochemistry

Electrochemical reactions on nanostructured noble electrodes have received much attention, however, the reaction mechanism and reaction kinetics are still difficult to be studied. Probe molecule can give an insight to the investigation of electrochemical reactions on noble electrodes with nanostructures. In this paper, the electrochemical process of p-aminothiophenol (PATP) adsorbed on the gold electrode was studied by electrochemical cyclic voltammetry and surface-enhanced Raman spectroscopy (SERS). Here, we used one-step sodium citrate reduction method (Frens method) to synthesize gold nanoparticles, which are used to construct the nanostructured gold electrode. The Raman electrolytic cell used was based on the traditional three-electrode electrolytic …

Multi-Scale Simulation Revealing The Decomposition Mechanism Of Electrolyte On Lithium Metal Electrode, Yan-Yan Zhang, Yue Liu, Yi-Ming Lu, Pei-Ping Yu, Wen-Xuan Du, Bing-Yun Ma, Miao Xie, Hao Yang, Tao Cheng

Journal of Electrochemistry

Lithium metal is considered as an ideal anode material for next-generation high energy density batteries with its high specific capacity and low electrode potential. However, the high activity of lithium metal can lead to a series of safety issues. For example, lithium metal will continuously react chemically with the electrolyte, forming unstable the solid electrolyte (SEI) films. In addition, lithium dendrites can be formed during cycling, which can puncture the SEI film and cause short circuits in the battery. These drawbacks greatly hinder the commercial application of lithium metal. To solve the above problems, it is important to understand the …

Preparation Of Pt@Basrtio3 Nanostructure And Its Properties Towards Photoelectrochemical Ammonia Synthesis, Jing Zhang, Rui-Xia Guo, Jian-Jun Fu, Shi-Bin Yin, Pei-Kang Shen, Xin-Yi Zhang

Journal of Electrochemistry

Ammonia is an important industrial raw material and a potential green energy. Using renewable energy to convert nitrogen into ammonia under ambient condition is an attractive method. However, the development of efficient photoelectrochemical ammonia synthesis catalysts remains a challenge. Perovskite such as BaSrTiO₃ (BST) is a good photocatalytic material. However, BST is active under ultraviolet light and has a high recombination rate of photogenerated electron-hole pairs. By dispersing precious metals, it can effectively regulate the absorption of sunlight by BST. In this work, we used a two-step method to prepare BST. The H₂PtCl₆·6H₂O …

Foldamers Reveal And Validate Therapeutic Targets Associated With Toxic Α-Synuclein Self-Assembly, Jemil Ahmed, Tessa C. Fitch, Courtney M. Donnelly, Johnson A. Joseph, Tyler D. Ball, Mikaela M. Bassil, Ahyun Son, Chen Zhang, Aurélie Ledreux, Scott Horowitz, Yan Qin, Daniel Paredes, Sunil Kumar

Chemistry and Biochemistry: Faculty Scholarship

Parkinson’s disease (PD) is a progressive neurodegenerative disorder for which there is no successful prevention or intervention. The pathological hallmark for PD involves the self-assembly of functional Alpha-Synuclein (αS) into non-functional amyloid structures. One of the potential therapeutic interventions against PD is the effective inhibition of αS aggregation. However, the bottleneck towards achieving this goal is the identification of αS domains/sequences that are essential for aggregation. Using a protein mimetic approach, we have identified αS sequences-based targets that are essential for aggregation and will have significant therapeutic implications. An extensive array of in vitro, ex vivo, and in vivo assays …

Carbohydrate Metabolism In Bacteria: Alternative Specificities In Adp-Glucose Pyrophosphorylases Open Novel Metabolic Scenarios And Biotechnological Tools, Jaina A. Bhayani, Maria Josefina Iglesias, Romina I. Minen, Antonela E. Cereijo, Miguel Ballicora, Alberto A. Iglesias, Matias D. Asencion Diez

Chemistry: Faculty Publications and Other Works

We explored the ability of ADP-glucose pyrophosphorylase (ADP-Glc PPase) from different bacteria to use glucosamine (GlcN) metabolites as a substrate or allosteric effectors. The enzyme from the actinobacteria Kocuria rhizophila exhibited marked and distinctive sensitivity to allosteric activation by GlcN-6P when producing ADP-Glc from glucose-1-phosphate (Glc-1P) and ATP. This behavior is also seen in the enzyme from Rhodococcus spp., the only one known so far to portray this activation. GlcN-6P had a more modest effect on the enzyme from other Actinobacteria (Streptomyces coelicolor), Firmicutes (Ruminococcus albus), and Proteobacteria (Agrobacterium tumefaciens) groups. In addition, we …

Synthesis, Characterization, And Thermal Investigation Of Metal Phosphites And Potential Implications For Astrobiology, Kimberly Faye Meyberg

Master of Science in Chemical Sciences Theses

The role of phosphorus in biochemistry is well understood. However, the route by which phosphorus was incorporated into early biomolecules on the prebiotic Earth is uncertain. Phosphate, the most prevalent species of phosphorus found in Earth’s geological record, is insoluble and unreactive with organics in aqueous environments. While the most abundant biogenic elements (C, N, H, O, and S) can be found in a volatile phase under terrestrial conditions, phosphorus cannot, suggesting that minerals must have been the main sources of phosphorus on the early Earth. One possible explanation is that phosphite was a major source of reduced, reactive phosphorus …

Low-Cost Adsorbent For Disinfection Byproduct Removal From Drinking Water, Savanna Vacek, Suraj Pochampally

Undergraduate Research Symposium Posters

Disinfection byproducts (DBPs) are harmful contaminants that are unintentionally created in disinfected water after chlorination. Activated carbon, often expensive and difficult to acquire in low-income and rural areas, has previously been used to remove DBPs from drinking water. Biochar is made from agricultural waste (i.e. feedstock) and has been identified as a low-cost yet effective adsorbent to remote contaminants from drinking water. This work focuses on the efficacy of biochar and activated carbon to remove DBPs from drinking water for the purpose of treating drinking water after emergency chlorination. This study has the potential to help water distributors and disadvantaged …

Identification Of Lipid Species: Potential Biomarkers For Early Detection Of Hepatocellular Carcinoma, Kit Yee Leung, Kaylee Freitas

Undergraduate Research Symposium Posters

Hepatocellular carcinoma (HCC) is the most common type of liver cancer. HCC is associated with cirrhosis. Poor survival rate of HCC is due to diagnosis of HCC at late stage.

Synthesis Of Modified Walnut Shell Biochar And Material Characterization In Ground Water Treatment, Maaike Parajes, Suraj Pochampally

Undergraduate Research Symposium Posters

Biochar (BC) is a carbon-rich material synthesized from the pyrolysis of biomasses and developed to remove soil and wastewater contaminants. The pyrolysis process involves thermally decomposing the organic materials in the absence of oxygen. Biochar has the potential to be an eco-friendly and effective adsorbent for heavy metals and toxic organic compounds. An adsorbent is a material that attracts other substances on its surface, chemically and physically. Walnut shells were chosen for the biochar modification to improve the surface morphology, pore structure, and adsorption capability.

Biochar Hydrophilicity Characterization By A Smartphone-Based Apparatus: Design, Construction, And Measurement Calibration, Emma Letourneau, Suraj Pochampally

Undergraduate Research Symposium Posters

Water contact angles are used to determine hydrophilicity, which is a material's attraction to water. A water contact angle of greater than 90 degrees indicates a hydrophobic material that repels water, whereas a contact angle of less than 90 degrees indicates a hydrophilic material [Fig. 1]. Water contact angles are measured through a goniometer, which can cost between $2000 to $10,000.

Biochar is a porous carbon material created from biological waste products, that is pyrolyzed (i.e. burned) in a low-oxygen, high heat environment. Biochar can be used to remove contaminants from water and remediate soil while reusing waste, making it …

Evaluating Alternative Ebullition Models For Predicting Peatland Methane Emission And Its Pathways Via Data–Model Fusion, Shuang Ma, Lifen Jiang, Rachel M. Wilson, Jeff P. Chanton, Scott Bridgham, Shuli Niu, Colleen M. Iversen, Avni Malhotra, Jiang Jiang, Xingjie Lu, Yuanyuan Huang, Jason Keller, Xiaofeng Xu, Daniel M. Ricciuto, Paul J. Hanson, Yiqi Luo

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

Understanding the dynamics of peatland methane (CH4) emissions and quantifying sources of uncertainty in estimating peatland CH4 emissions are critical for mitigating climate change. The relative contributions of CH4 emission pathways through ebullition, plant-mediated transport, and diffusion, together with their different transport rates and vulnerability to oxidation, determine the quantity of CH4 to be oxidized before leaving the soil. Notwithstanding their importance, the relative contributions of the emission pathways are highly uncertain. In particular, the ebullition process is more uncertain and can lead to large uncertainties in modeled CH4 emissions. To improve model simulations of CH4 emission and its pathways, …

Controlling Unequal Surface Energy Results Caused By Test Liquids: The Case Of Uv/O3 Treated Pet, Bilge N. Altay, Paul D. Fleming, Md Arifur Rahman, Alexandra Pekarovicova, Bruce Myers, Cem Aydemir, Arif Karademir

Articles

Ultraviolet/ozone (UV/O3) treatment has been reported to be an effective method to modify properties such as wettability, adhesion or adsorption of plastic surfaces. The change in the surface is measured by contact angle analysis, which employs liquids and their surface tensions (ST) to estimate the surface energy (SE). We found two different practices in the scientific community: (1) the majority of researchers adopted the ST value of liquids from the literature, while (2) other researchers conducted real-time measurements in the lab under ambient conditions prior to SE estimation. To the best of our knowledge, there is no study that compares …

The Synthesis And Purification Methodology Of An Intermolecular Pyrophosphate Sensor: Applications For The Quantitative Polymerase Chain Reaction, Ethan Gevedon

Honors Projects

The optimized synthesis and purification methodology for an intermolecular pyrophosphate sensor scaffold molecule was performed: high performance liquid chromatography afforded the scaffold in excellent purity and yield. The applications of the sensor assembly in the quantitative polymerase chain reaction were discussed, and preliminary results show that

Investigating Ionic Current Rectification As A Means Of Controllable Drug Delivery Using Silica Nanoparticles And Nano Porous Membranes, Katie L. Nolan

Honors College Theses

This project investigates a novel ionic current rectification (ICR) phenomenon created by the opening and closing of nanopores by charged silica nanoparticles (SNPs) under electrophoretic flow. This voltage-controlled opening and closing of the pores can be exploited to allow delivery of nicotine through the pores at programmable intervals. The ICR phenomenon was thoroughly investigated by varying pH, buffer concentration, SNP concentration, and applied voltage range. The mechanism was also verified by testing with a 2-, 3-, and 5-electrode system. Potential cake layer formation was demonstrated in a longer ICR test, and the implications of this on the drug delivery mechanism …

Synthesis And Characterization Of Alkyne-Functionalized Photo-Cross-Linkable Polyesters, Warrick Ma, Xiaochu Ding, Ying Chen, Yadong Wang

Michigan Tech Publications

An alkyne-functionalized elastomer derived from sebacic acid, 1,3-propanediol, and alkyne-functionalized serinol is synthesized via melt condensation. A low-power UV lamp triggers the cross-linking rapidly via thiol-yne click chemistry. The cross-linking behavior is studied by photorheology and NMR spectroscopy. The resultant elastomer possesses mechanical properties similar to those of human soft tissues and exhibits in vitro degradability and good cytocompatibility.

Hydrolytically Degradable Thermosets With Tunable Degradation Profiles Via Ketal-Based Crosslinks, Benjamin Alameda

Dissertations

Thermoset polymer networks are ubiquitous in the construction of high-performance materials due to their excellent mechanical properties, solvent resistance, and thermomechanical performance. However, the crosslinked structure that instills these materials with favorable performance also makes them incredibly resistant to degradation and are nearly impossible to recycle – adding to the ever-growing problem of plastic pollution. Hydrolytically degradable thermosets have emerged as a potentially sustainable alternative to traditional thermosets by affording networks that are inherently degradable in aqueous environments. This dissertation focuses on the development of hydrolytically degradable thermoset networks with tunable degradation behavior through the implementation of ketal-based crosslinks. Given …